FIGGS Faint Irregular Galaxies GMRT Survey - Overview, observations and first results
萨比恩度数象征
Aries白羊座1A woman has risen from the water; a seal has emerged also, and is embracing her.一位女子从水面升起，一只海豹也随之出现，与她相拥。
喜剧演员正款待他的一群朋友。
3A cameo shows the profile of a man that suggests the outline of his country.贝壳浮雕上一个男子的侧脸令人想起他的祖国的样子。
4Two lovers are strolling through a secluded walk.恋人正漫步着穿过一条幽谧的小径。
5A white triangle is seen; it has golden wings.白色三角有着金色的边（精灵拥有希望之翼）。
6A black square stands firmly, illumined red on one side.黑色的方块稳稳的伫立，其中的一面被照得通红。
男子自满于同时在两个独立领域里表现出的天赋。
8A large old-fashioned woman's hat is revealed with streamers flying in a stiff breeze from the east.东边的和风吹起，一顶很大的旧式女帽下直直的飘带迎风飞舞。
9A seer gazes intently into a crystal ball before him.先知专注地凝视着他面前的水晶球。
10A savant is revealed, a man who has created new forms for old symbols that have lost their meaning.一位学者创造了新的符号来表征原来失去了意义的旧事物。
11The president of the republic or the ruler of his country is presented.共和国的领导人或国家的统治者上台了。
齿轮标准
AGM A
STANDARD
AGMA Sound Manual
Sound Manual AGMA 299.01
[Tables or other self-supporting sections may be quoted or extracted in their entirety. Credit lines should read: Extracted from AGMA 299.01, Sound Manual, with the permission of the publisher, the American Gear Manufacturers Association, 1500 Ring Street, Suite 201, Alexandria, Virginia 223141. AGMA standards are subject to constant improvement, revision or withdrawal as dictated by experience. Any person who refers to AGMA Technical Publications should be sure that the publication is the latest available from the Association on the subject matter.
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Reproduced By GLOBAL T-= P -ENGINEERING DOCUMENTS C v E With The Permission Of A G M A -7 Under Royalty Agreement
A G M A 299.01 Part I 1978 Part II 1980 Part III 1980 (All Reaffied January 1995)
新大学法语课后答案精选版
新大学法语课后答案精选版新大学法语课后答案Company number【1089WT-1898YT-1W8CB-9UUT-92108】新大学法语 1 课文翻译及课后参考答案UNITE?1第一单元TEXTE A致意Ⅰ——您好，夫人。
——近好，伊夫。
您好吗？——很好，谢谢。
您呢？——我也很好，谢谢。
Ⅱ——喂？——你好，我是法尼。
——啊，你好，法尼。
你好吗？——很好，你呢？——很好。
EXERCICES SUR LE TEXTEⅠ1. Yves2. vous3. merci4. et toi5. aussi6. c’estⅡ1.d2. c3. b4. aⅢ 2-3-1-6-5-4-7Ⅳ见字母表TEXTE B介绍与自我介绍Ⅰ——你好，雅克。
——你好，埃里克。
——给我介绍一下，（这是）杜朗夫人。
她是工程师。
——很高兴（认识你）。
我叫雅克·迪迪耶。
我是教师。
——很高兴（认识你），迪迪耶先生。
Ⅱ——阿丽丝，你好。
——你好，让。
——这是谁？——我妹妹。
——她叫什么名字？——她叫玛丽，她上学了。
——她已经上学了？——是的。
她六岁了，她学习很好。
——你们住在哪里？——我们住在学院路。
EXERCICES SUR LE TEXTEⅠ 1. suis 2. es 3. est 4. est 5. sommes 6. êtes 7. sont 8. sontⅡ 1. c 2..e 3. b 4. a 5. dⅢ1.Bonjour2. Salutprésente cem’appelle masuis nomMonsieur aàbienⅣ 横排：sept, dix, neuf, un, six, huit竖排：trois, cinq, deux, troisUNITE 2 第二单元TEXTE A邀请Ⅰ——你好，雅娜。
——你好，菲利普。
——星期日你干什么？——哦，我。
——我们去看电影好吗？——好啊！——那么，星期日9点钟在电影院门口（见面）行吗？——可以，星期日见。
thehitchhikersguidetothegalaxy银河系漫游指南
Searching for the answers to life, the universe, and everything? Well look no further…The Hitchhikers Guide to the GalaxyBy Douglas AdamsPublished by Serious Productions© 1976A Sci-fi thrillerPage Count: 216Your Guide to SurvivalBy ATPlanning on taking a quick stop by Ursa Minor? Just don’t forget the number one rule of thumb when traveling across the galaxy: Always bring a blanket. Tips like these are shared periodically throughout The Hitchhiker’s Guide to the Galaxy, by Douglas Adams. In it, the deepest questions of the universe will at last be answered. The protagonist, Arthur Dent, is the sole survivor of planet Earth since it was destroyed for the means of making an intergalactic highway. Dent finds himself aboard a spaceship with Ford Prefect, his quirky best friend. Together they make their way across the galaxy through a series of highly improbable coincidences: stumbling upon the president of the galaxy, surviving in the vacuum of space, and finding the legendary planet of Magrathea. The novel’s plot revolves around what happens to this unlikely crew as they are the first beings in five million years to reach Magrathea. This concept of life outside of Earth and traveling through great distances of space is what will likely keep the reader reading.In the beginning this world renowned book pulls readers in through Adams unique tone including multiple hilarious scenes that will leave one laughing out loud. The book is comprised of twenty-two chapters, each short in length making the book a quick and easy read. It also has many elements that many teenagers enjoy including humor while maintaining a thought-provoking plot line.The strong suit of The Hitchhiker’s Guide to the Galaxy is definitely its extensive creativity. Within the book there is another book entitled The Hitchhiker’s Guide to the Galaxy, where one will find descriptions of creatures and places throughout the galaxy. Some of its excerpts being literally out of this world! Who could have thought of its description of the Babble Fish: “it feeds on brainwave energy received not from its carrier but from those around it. It absorbs all unconscious mental frequencies from this brainwave energy to nourish itself.” These overly complex ideas put a comic spin on the plot which is another strength. However straying from the plot to explain something can often make readers confused. This drift from the plot resulted in a very disorganized composite of certain scenes in the book. Adams may have chose to include this skipping around to lighten up the more serious parts of the book and remind the reader that it is a comic novel. In other words those looking for an uplifting and humorous book about life’s greatest mysteries will surely find The Hitchhiker’s Guide to the Galaxy very entertaining. After reading this, one can not help but ponder the very insignificance that our whole planet really has.Douglas Adams’ other books exhibit his passion for science fiction, specifically the larger world that exists outside of Earth. The Hitchhiker’s Guide to the Galaxy was adapted into a mini TV series, and a full length feature film, in 2005. Adams has a series of follow up books entitled The Restaurant at the End of the Universe, Life the Universe and Everything, So Long, and Thanks for all the Fish, and many others. These novels include many jokes originating from The Hitchhikers Guide to the Galaxy. Adams’ career of wild success spun off of this one ground breaking novel, a truly remarkable feat.Unfortunately his career came to an abrupt end when he died at the age of forty-nine in2001. His legacy lives on through this, and many other captivating books that will leave one wondering whether or not we are indeed alone in the universe.Below is given annual work summary, do not need friends can download after editor deleted Welcome to visit againXXXX annual work summaryDear every leader, colleagues:Look back end of XXXX, XXXX years of work, have the joy of success in your work, have a collaboration with colleagues, working hard, also have disappointed when encountered difficulties and setbacks. Imperceptible in tense and orderly to be over a year, a year, under the loving care and guidance of the leadership of the company, under the support and help of colleagues, through their own efforts, various aspects have made certain progress, better to complete the job. For better work, sum up experience and lessons, will now work a brief summary.To continuously strengthen learning, improve their comprehensive quality. With good comprehensive quality is the precondition of completes the labor of duty and conditions. A year always put learning in the important position, trying to improve their comprehensive quality. Continuous learning professional skills, learn from surrounding colleagues with rich work experience, equip themselves with knowledge, the expanded aspect of knowledge, efforts to improve their comprehensive quality.The second Do best, strictly perform their responsibilities. Set up the company, to maximize the customer to the satisfaction of the company's products, do a good job in technical services and product promotion to the company. And collected on the properties of the products of the company, in order to make improvement in time, make the products better meet the using demand of the scene.Three to learn to be good at communication, coordinating assistance. On‐site technical service personnel should not only have strong professional technology, should also have good communication ability, a lot of a product due to improper operation to appear problem, but often not customers reflect the quality of no, so this time we need to find out the crux, and customer communication, standardized operation, to avoid customer's mistrust of the products and even the damage of the company's image. Some experiences in the past work, mentality is very important in the work, work to have passion, keep the smile of sunshine, can close the distance between people, easy to communicate with the customer. Do better in the daily work to communicate with customers and achieve customer satisfaction, excellent technical service every time, on behalf of the customer on our products much a understanding and trust.Fourth, we need to continue to learn professional knowledge, do practical grasp skilled operation. Over the past year, through continuous learning and fumble, studied the gas generation, collection and methods, gradually familiar with and master the company introduced the working principle, operation method of gas machine. With the help of the department leaders and colleagues, familiar with and master the launch of the division principle, debugging method of the control system, and to wuhan Chen Guchong garbage power plant of gas machine control system transformation, learn to debug, accumulated some experience. All in all, over the past year, did some work, have also made some achievements, but the results can only represent the past, there are some problems to work, can't meet the higher requirements. In the future work, I must develop the oneself advantage, lack of correct, foster strengths and circumvent weaknesses, for greater achievements. Looking forward to XXXX years of work, I'll be more efforts, constant progress in their jobs, make greater achievements. Every year I have progress, the growth of believe will get greater returns, I will my biggest contribution to the development of the company, believe inyourself do better next year!I wish you all work study progress in the year to come.。
光芒的 深不可测的英文单词
光芒的深不可测的英文单词English:The profound and unfathomable brilliance of the light radiated through the universe, piercing through the darkness and illuminating the unknown realms of existence. It is a luminous spectacle that evokes a sense of wonder and awe, captivating the hearts and minds of all who behold its magnificent splendor. This enigmatic luminescence carries within it the mysteries of the cosmos, a mesmerizing display of cosmic energy and celestial beauty. It is a beacon of hope and inspiration, guiding the way through the infinite expanse of the cosmos and igniting the imagination with its boundless potential and unfathomable depth.Translated content:光芒深邃而不可测的辉煌穿越宇宙，穿透黑暗，照亮着未知的存在领域。
这是一场光明的奇观，引发了人们对奇迹和敬畏的感觉，迷住了所有见证其壮丽光辉的心灵。
这种神秘的发光包含着宇宙的奥秘，是宇宙能量和天体美的迷人展示。
它是希望和灵感的指引，引领着我们穿越无限的宇宙，用其无限的潜力和深不可测的深度点燃了我们的想象力。
制作宇宙飞船英语作文5句话六年级
制作宇宙飞船英语作文5句话六年级全文共6篇示例，供读者参考篇1Making a Spaceship: A Sixth Grader's DreamEver since I was a little kid, I've been fascinated by space. The twinkling stars in the night sky, the mysteries of galaxies far, far away, and the idea of exploring new worlds beyond our own planet – it all captivated me. And what better way to explore the cosmos than by building my very own spaceship? That's right, folks, I'm going to tell you how I'd make a spaceship if I had the chance!First things first, I'd need a really awesome team to help me out. I'd gather the smartest kids from my class, the ones who ace all the science tests and can build crazy cool stuff out of LEGOs. We'd call ourselves the "Stellar Squadron" or something cool like that. Together, we'd come up with the most epic design for our spaceship.Now, I know what you're thinking: "But how can a bunch of kids build a spaceship? That's way too complicated!" Well, let me tell you, we've got big brains and even bigger dreams! We'd startby studying all the latest space technology and learning from the best engineers and scientists out there.Our spaceship would have to be strong enough to withstand the intense pressures of space travel, so we'd use a special kind of super-strong metal alloy for the outer hull. Maybe we could even find a way to make it out of that cool stuff they use on the space shuttles!Next up, we'd need a powerful propulsion system to get our baby off the ground and into orbit. Rocket engines are so last century, though. We're thinking something more cutting-edge, like an ion thruster or maybe even an antimatter drive! Yeah, that's the kind of crazy, futuristic tech we're going for.Speaking of space walks, our spaceship would definitely have an airlock and a fancy spacesuit closet. Can you imagine how cool it would be to float around outside, doing repairs or collecting space samples? We'd be like real-life astronauts!And let's not forget about the most important part of any spaceship: the controls! We'd have a super high-tech command center with all sorts of fancy buttons, switches, and monitors. Maybe we could even get some of those cool holographic displays like they have in the movies!Can you picture it? A bunch of sixth-graders blasting off into the great unknown, exploring new worlds, and making groundbreaking discoveries? It might sound like a crazy dream, but hey, someone has to be the first kids in space!So, there you have it, folks – my master plan for building the coolest, most high-tech spaceship the galaxy has ever seen. With a little hard work, a lot of determination, and maybe a dash of magic, anything is possible. Who knows, maybe one day you'll see the Stellar Squadron's spacecraft soaring through the cosmos, boldly going where no kids have gone before!篇2Making a SpaceshipWow, can you imagine how awesome it would be to build your own spaceship? I think about that all the time! Blasting off into outer space and exploring strange new worlds. How cool would that be? Okay, let me tell you my plan for making the most epic spaceship ever!First off, we need to think about the shape. Most spaceships are like rockets - tall and thin to cut through the atmosphere easily. But that's kind of boring if you ask me. I'm thinking we make it more like a flying saucer, you know, like the alien shipsyou see in movies! A big round disc with a dome on top. That would be so rad to fly around in.For the outside, we'd want some kind of super strong metal that can withstand extreme temperatures and meteor strikes when we're cruising through space. Maybe titanium or something. And it would need a protective force field too to keep us safe. The force field could have a crazy color like bright green or purple - how cool would that look zooming around?!On the inside, we'd need living quarters for the crew with bunk beds, a kitchen, bathrooms, and a lounge area to hang out. Oh and don't forget an insane entertainment system with huge viewscreens and the latest video games! We'd basically be living on this thing for months or years at a time when exploring distant galaxies.For getting around, we'd need an advanced propulsion system way better than boring old rocket engines. I'm talking electrodrive ion propulsion or something wild like that. We'd be able to achieve incredible speeds and get basically anywhere we want to go super fast.There would have to be a sick navigation deck with hologram star maps and stuff. Piloting this beast would be like something out of Star Wars! We'd have all kinds of crazy sensorsand long-range scanners to analyze anything we encountered too. Imagine being the first humans to explore a new solar system and make groundbreaking discoveries!And of course we'd need a transporter room to beam down to planet surfaces. Maybe we could even have shuttlecraft that could detach and land on worlds too big to beam directly onto. Speaking of shuttles, our ship would need a huge landing bay to store them in.Defending ourselves is important as well. We'd pack the most cutting-edge laser cannons, proton torpedoes, and photon missile launchers money can buy. If any hostile aliens tried to mess with us, we'd be ready to go! Hopefully we could make friends with cool alien civilizations instead though.Another key system is the replicator room to create any supplies we need out of pure energy. Need to replicate a new spacesuit? No problem! Craving pizza for movie night? You got it! Just think how handy that would be on long voyages.I haven't even gotten to the best part yet - the holodeck! This would be a huge room where you could create any environment imaginable with life-sized realistic holograms and force fields. Battling AI robots on an alien planet one minute,then relaxing on a Hawaii beach the next. A holodeck would let us safely experience the most incredible adventures.There's so much more to designing the ultimate spaceship, but I'm already out of breath just thinking about it all. Aself-sustaining food replicator system, powerful sensor arrays, tractor beams, you name it! Building something capable of interstellar and even intergalactic travel would take a team of the best scientists and engineers in the world.I guess for now I'll have to keep dreaming about the day I can captain my very own star cruiser. Just a kid from Earth who gets to lead a crew of daring space explorers to places nobody has ever gone before. Pushing the boundaries of the unknown and boldly going where no one has gone before! Wait a second...I think I heard that somewhere before. Oh well, never mind! When I get older and finish school, I'm going to make my spaceship dreams a reality. Maybe I'll be able to take you all along for the ride one day too? Wouldn't that be the adventure of a lifetime? Aww yeah, now you know what I'll be doodling about in my notebook during math class! To infinity and beyond!篇3Making a SpaceshipImagine soaring through the endless depths of space, leaving Earth behind to explore strange new worlds and galaxies! That's the dream that captured my imagination ever since I was a little kid watching sci-fi movies. I've always been fascinated by space travel and the mysteries of the cosmos. What alien civilizations might we encounter out there? What mind-blowing discoveries await us amongst the stars?So buckle up, because here's my master plan for building the greatest spaceship of all time!First off, we need a killer design - something that looks powerful and futuristic, but also streamlined for maximum speed through the vacuum of space. Maybe an arrowhead shape with some wicked fins and thruster nozzles? Let's throw in some gnarly weapon banks too, just in case we run into any hostile aliens.For the hull, we can't just use regular old metal. That wouldn't be nearly strong or lightweight enough. I'm thinking some kind of super-tough, reinforced carbon nanotube composite. Or maybe an exotic new material forged in a ultrahot stellar nursery? Whatever it is, it needs to be able to withstand everything the cosmos can dish out - cosmic rays, meteor showers, you name it.The power core is where things get really exciting. Forget about conventional rocket engines - we need something a lot hotter and crazier to achieve faster-than-light travel. I'm talking an antimatter reactor or maybe even an artificial micro black hole powering an Alcubierre warp drive! Sure, it sounds dangerous, but that's a risk I'm willing to take for the chance to boldly split infinities.While those self-replicating miners are hard at work, the construction of the spaceship itself can begin on a sprawling zero-gravity orbital shipyard. Armies of AI-controlled drones will buzz around, assembling each component using advanced forms of atomic 3D printing and molecular manufacturing.Speaking of AI, our ship definitely needs to be equipped with a superintelligent computer brain to handle all the key operations. Piloting, navigation, life support, you name it - the AI will be jacked into the core systems, with its distributed quantum data-Banks allowing it to process a gazillion calculations per nanosecond. It'll be smarter than a thousand Einsteins combined!And what kind of epic spaceship would be complete without a crack crew of brave astro-explorers? We'll need elite pilots to helm the ship, brainy science officers to analyze new phenomena,and maybe even a few brawny security grunts to rough up any space pirates dumb enough to mess with us.Oh, and let's not forget all the cool support facilities a ship this size will need - hydroponic bio-domes for growing food, holographic recreation lounges for downtime, and of course a super-slick medbay with all the latest tech to heal anyone who gets spaced during a skirmish.With all those key components in place, we'll be ready to engage the hyperdrive and punch the unchartable cosmic depths in search of strange new worlds, new life, and new civilizations! Who knows what we might find out there - maybe even hyper-intelligent beings who can share the secret of harnessing dark energy or breaching the very fabric of reality itself.Just imagine the places we'll go and the things we'll see on a ship like this! Black hole megastructures constructed by Level IV cosmic civilizations. Entire galaxies remade into bespoke fractal configurations by posthuman überminds. Heck, we might even bear witness to the Big Crunch and have a front row seat for the birth of a new infinite multiverse cycle!Those are just some of the possibilities that excite me about interstellar exploration and spacecraft engineering. By the timeI'm done designing my perfect ship, it'll be able to traverse a million cosmic voids and carry humanity to walk amongst the very face of God (or gods) themselves.So what do you think? Are you ready to climb aboard and shunt into hyperspace for the grandest adventure imaginable? If so, then let's get building! Our stargating destiny awaits!篇4Making a SpaceshipEver since I was a little kid, I've dreamed of blasting off into space and exploring strange new worlds. I used to spend hours just staring up at the stars, imagining what kind of alien beings might be living on distant planets. Would they be little green men like you see in the cartoons? Or maybe huge, scaly monsters with multiple heads and tentacles? Who knows - the universe is a vast and mysterious place full of possibilities!Last summer, my friend Jacob and I decided we were finally going to make our dream of space travel a reality. We were going to build our very own spaceship right in his backyard! It was an ambitious plan for sure, but we were determined to succeed no matter what. After doing some research online and watching a bunch of YouTube tutorials, we made a list of all thematerials we would need: aluminum foil, cardboard boxes, duct tape, plastic bottles, an old bike tire, and a bunch of other odds and ends we scrounged up from around the house and garage.The first step was to construct the main body of the ship using the biggest cardboard boxes we could find. We cut holes for windows and used duct tape to join all the pieces together into one hollow capsule shape. Jacob's mom helped us by spray painting the whole thing a sleek silver color. That thing was going to look so awesome rocketing through the cosmos!Next up was the control room area where the pilot (aka me) would get to operate all the high-tech equipment. We covered the inside walls with aluminum foil to make it look all futuristic and space-age. Then we taped a bunch of plastic bottles together into clusters to serve as the control panels and buttons. Jacob even found an old video game steering wheel that we could use for navigating the ship. This thing was really coming together!But of course, no spaceship would be complete without thrusters and engines to make it go. For that, we used a whole bunch of those plastic bottles arranged into cone shapes, along with the old bike tire for the main engine at the back. I can still remember Jacob and me furiously pumping air into those bottles,making rocket sounds with our mouths as we fantasized about accelerating into hyperdrive.Once the spaceship was all built and decked out, Jacob's little sister got to be our first test passenger. We buckled her into the commander's chair and put on a space helmet (which was really just an upside-down plastic storage bin with a visor cut out). Then we grabbed those little noisemaker things that unravel when you spin them and started running around the ship, shaking it and making lots of rumbling rocket noises. Jacob's sister seemed to get a real kick out of it, giggling and bouncing up and down while we simulated blasting off into the great unknown.Eventually summer had to come to an end, and with the changing seasons our spaceship started showing some wear and tear. The foil covering got all torn and dented, the plastic bottles cracked from being kicked around too much, and a big rain storm pretty much did the rest. We had to dismantle the whole thing and stash the remains back in the garage before winter hit. It was kind of sad seeing our spaceship dream come to an end. But you know what? We'll always have those incredible memories of all the fun we had building and playing in it. Maybe we didn't make it to the Andromeda galaxy, but that spaceshipstill took us on the grandest adventure two knuckleheaded kids could ever imagine.Who knows, in another decade or two I might be writing this story from the surface of Mars, reminiscing about the humble backyard beginnings that sparked my passion for space travel and exploration. Jacob and I finally made it you guys! All because of that homemade spaceship we built back in 6th grade. I'll never forget those days of cutting up cardboard boxes, taping bottles together, and just letting our creativity and imagination run wild. It just goes to show that you're never too young to start pursuing your biggest dreams and ambitions in life. Even if that means building your own spaceship!篇5Making a SpaceshipHave you ever dreamed of traveling to other planets and galaxies? Building your very own spaceship is the first step to exploring the vast mysteries of outer space! It may seem like an impossible task, but with some hard work and determination, you can construct an awesome rocket that will allow you to soar through the cosmos.The first thing you need to do is gather all the necessary materials. For the body of the ship, you'll want a large cylindrical container, like an empty trash can or barrel. This will form the main fuselage where the crew will sit. You can use cardboard tubes from wrapping paper or shipping containers to make the nose cone and exhaust nozzles. Lots of aluminum foil will come in handy for covering the exterior and giving it that sleek, futuristic look.Next, you have to work on the propulsion system that will actually get your spaceship off the ground. One option is to build a solid fuel rocket motor using a cardboard tube loaded with a mixture of powdered charcoal and sugar as the propellant. For safety reasons, it's best to get an adult to supervise this part! An easier alternative is making cold-air rockets that use compressed air or carbonated gases to produce thrust.Once you have the basic rocket assembled, it's time to make it look awesome and spaceworthy! Use spray paint to coat the exterior in classic spacecraft colors like white, gray, black or metallic silver. Cut funky window shapes out of construction paper and glue them on as portholes. Bend pipe cleaners and attach them as antennae, sensors or landing gear. Get creative and let your imagination run wild!The most important final step is to deck out the interior living quarters where the astronauts will live during their intergalactic journeys. Fashion control panels from cardboard, buttons and dials. Use blankets and pillows for bunks and seats. Don't forget to pack a bunch of snacks, books and games to fend off boredom on those long voyages through the void of space.There you have it - your very own fully functional spaceship ready to carry you to the farthest reaches of the universe! All that's left is to pencil in your first test launch countdown. May it have a successful liftoff and bring you one step closer to experiencing the thrill of space exploration. The planets, stars, and maybe even alien civilizations on distant worlds are calling to intrepid young astronauts like you. So suit up, strap in, and get ready for an out-of-this-world adventure!篇6Making a SpaceshipEver since I was a little kid, I've always dreamed of traveling to outer space and exploring other planets. Whenever I look up at the night sky, I'm filled with wonder and curiosity about what's out there among the twinkling stars. That's why I decided that formy science fair project this year, I want to make a model of a spaceship that could actually fly to places like Mars or Jupiter!I started by researching different spacecraft designs from NASA and other space agencies. There are so many amazing rockets and shuttles that have already made incredible voyages through the cosmos. The Saturn V rocket that took astronauts to the Moon is one of the coolest looking ones, with its huge boosters and sleek white body. But my favorite has to be the Space Shuttle, with its reusable design and cool robotic arm.After looking at a ton of pictures and diagrams online, I decided to base my model spaceship on the Space Shuttle, but with some modifications of my own. I'm going to make the body a bit bigger so there's more room for supplies and living space. And instead of solid rocket boosters, I want to use a more advanced propulsion system like an ion thruster, since those could provide longer thrust for interplanetary travel.Next, I gathered all the materials I would need to actually build the model. I used foam core boards for the body and wings, along with balsa wood reinforcements on the inside. For the thrusters and other detailed parts, I'm working with modeling clay that can be shaped and painted. It's been really fun putting all the pieces together and seeing my design come to life!My spaceship has a crew compartment that can fit four astronauts, along with supplies and science experiments. There's a robotic arm for retrieving samples or doing repairs outside. And I included two small landers that can detach and land on extraterrestrial surfaces. I even made the wings adjustable so the ship can better maneuver during launch and atmospheric reentries.Building this model spaceship has been an awesome learning experience. Even though it's not a real spacecraft that can actually fly to other planets, the process of designing and constructing it has taught me so much about physics, engineering, and space exploration. Maybe if I keep working at projects like this when I'm older, I could have an amazing job helping create the next generation of spaceships and rockets. For now though, I'm just really excited to enter my model in the science fair and share my dreams of space travel with everyone! Exploring the mysteries of the universe is something us humans are surely destined for.。
介绍猫头鹰的英语作文
Owls:The Enigmatic Night HuntersOwls are among the most fascinating and mysterious birds in the world. Known for their distinctive appearance,nocturnal habits,and haunting calls,these birds have captured the imagination of people across cultures and centuries.This essay will explore the characteristics, behavior,habitat,and ecological importance of owls,as well as their interactions with humans.Characteristics of OwlsOwls belong to the order Strigiformes and have several distinctive features:Physical Appearance:Owls are medium to large-sized birds with rounded heads,large forward-facing eyes,and a facial disk that helps direct sound to their ears.Their plumage is often cryptically colored,allowing them to blend into their surroundings.Owls have strong,hooked beaks and sharp talons for catching and killing prey.Size and Lifespan:The size of owls varies depending on the species.The great horned owl,one of the largest species,can reach lengths of up to 25inches with a wingspan of around55inches.In contrast,the elf owl, one of the smallest species,measures about5-6inches in length with a wingspan of around10inches.Owls can live for several decades,with some species reaching up to20years or more in the wild.Adaptations:Owls have several adaptations that make them successful nocturnal hunters.Their large eyes provide excellent night vision,while their asymmetrical ears help pinpoint the location of sounds.Owls' feathers are specially adapted for silent flight,allowing them to approach prey without being detected.Their powerful talons and beaks enable them to capture and kill a variety of prey.Behavior and Hunting TechniquesOwls exhibit a range of interesting behaviors and hunting techniques:Diet and Foraging:Owls are carnivorous and primarily feed on small mammals,birds,insects,and other vertebrates.They are opportunistic hunters and will eat whatever prey is available in their environment. Owls use their keen senses of sight and hearing to locate prey,often hunting from a perch and swooping down to capture their target.Some species,like the barn owl,specialize in hunting rodents,while others, like the snowy owl,may hunt larger prey such as hares and ducks.Nesting and Breeding:Owls typically nest in tree cavities,abandoned nests of other birds,or on the ground,depending on the species.During the breeding season,males perform courtship displays,including vocalizations and flight displays,to attract females.Females lay2-6eggs, and both parents take turns incubating the eggs and feeding the chicks once they hatch.The chicks fledge after about4-6weeks but may remain dependent on their parents for several months.Vocalizations and Communication:Owls are known for their distinctive calls,which they use to communicate with each other.These calls can serve various purposes,including establishing territory,attracting mates, and signaling alarm.Each species has its own unique set of vocalizations, ranging from hoots and screeches to whistles and barks.Habitat and DistributionOwls are found in a wide range of habitats across the globe:Geographic Range:Owls are distributed worldwide,from the Arctic to the tropics,and are found on every continent except Antarctica. Different species have distinct ranges,with some,like the barn owl, found on multiple continents,while others,like the elf owl,are more restricted to specific regions.Preferred Habitats:Owls inhabit a variety of environments,including forests,grasslands,deserts,wetlands,and urban areas.They are highly adaptable and can thrive in both natural and human-altered landscapes. Some species,like the snowy owl,prefer open tundra,while others,like the barred owl,thrive in dense forests.Ecological ImportanceOwls play a crucial role in their ecosystems:Predator-Prey Dynamics:As predators,owls help regulate the populations of their prey species,such as rodents and insects.This maintains a balance in the ecosystem and prevents overpopulation, which can lead to habitat degradation.Owls are also prey for larger predators,including eagles and large mammals,contributing to the overall biodiversity of their habitats.Indicator Species:Owls are considered indicator species,meaning their presence and health can provide valuable information about the condition of their habitats.Healthy owl populations often indicate healthy ecosystems with good prey availability and minimal human disturbance.Interactions with HumansThe relationship between owls and humans is complex and multifaceted:Conservation and Threats:Many owl species face threats from habitat loss,pollution,and human disturbance.Deforestation,urbanization,and agricultural expansion can destroy nesting sites and reduce prey availability.Conservation efforts focus on protecting critical habitats, reducing human impact,and addressing threats such as pesticide use and climate change to ensure the survival of owl populations.Ecotourism and Education:Owls are popular attractions for birdwatchers and nature enthusiasts.Responsible ecotourism can raise awareness about owl conservation and generate funding for conservation cational programs in nature reserves, wildlife sanctuaries,and schools also play a vital role in promoting owl conservation and the importance of healthy ecosystems.Cultural Significance:Owls hold a special place in the cultures of many communities.They are often featured in folklore,mythology,art,and literature as symbols of wisdom,mystery,and protection.Their presence in the natural world is a reminder of the beauty and diversity of wildlife.ConclusionOwls are remarkable birds that play a vital role in the health and balance of ecosystems around the world.Their unique characteristics,nocturnal behavior,and ecological importance make them key components of the world's biodiversity.Understanding and appreciating owls is essential for the preservation of natural environments and the continued coexistence of humans and wildlife.By fostering a deeper appreciation for owls and supporting conservation efforts,we can ensure that these enigmatic night hunters continue to thrive and inspire future generations.Protecting owls means safeguarding the rich and diverse ecosystems they inhabit,ultimately benefiting all forms of life on our planet.。
GMATOG11黄皮正确句子138
OG11黄皮正确句子1381. Although a surge in retail sales has raised hopes that a recovery is finally underway, many economists say that without a large amount of spending the recovery might not last.2. Of all the vast tides of migration that have swept through history, perhaps none was more concentrated than the wave that brought 12 million immigrants onto American shores in little more than three decades.3. Diabetes, together with its serious complications, ranks as the nation's third leading cause of death, surpassed only by heart disease and cancer.4. A survey by the National Council of Churches showed that in 1986 there were 20,736 female ministers, almost 9 percent of the nation’s clergy, double the figure for 1977.5. As its sales of computer products have surpassed those of measuring instruments, the company has become increasingly willing to compete for the mass market sales it would in the past have conceded to rivals.6. Like the Brontes and Brawnings, James Joyce and Vrginia Woolf are often subjected to the kind of veneration that blurs the distinction between the artist a-d the human being.7. Carnivorous mammals can endure what would otherwise be lethal levels of body heat because they have a heat-exchange network that keeps the brain from getting too hot.8. Rising inventories, if not accompanied by corresponding increases in sales, can lead to production cutbacks that would hamper economic growth.9. Sunspots, vortices of gas associated with strong electromagnetic activity, are visible as dark spots on the surface of the Sun but have never been sighted on the Sun's poles or equator.10. Unlike those in the United States, Japanese unions appear reluctant to organize lower-paid workers.11. Warning that computers in the United States are not secure, the National Academy of Sciences has urged the nation to revamp computer security procedures, institute new emergency response teams, and create a special nongovernment organization to take charge of computer security planning.12. After gradually declining to about 39 hours in 1970, the workweek in the United States has steadily increased to the point that the average worker now puts in an estimated 164 extra hours of paid labor a year.13. As Hurricane Hugo approached the Atlantic coast, it increased dramatically in strength, becoming the tenth most intense hurricane to hit the United States mainland in the twentieth century and the most intense since Camille in 1969.14. The commission has directed advertisers to restrict the use of the word "natural" to foods that do not contain color or flavor additives, chemical preserva¬tives, or anything that has been synthesized.15. The Iroquois were primarily planters, although they supplemented their cultivation of maize, squash, and beans with fishing and hunting.16. Unlike the honeybee, the yellow jacket can sting repeatedly without dying and carries a potent venom that can cause intense pain.17. None of the attempts to specify the causes of crime explains why most of the people exposed to the alleged causes do not commit crimes and, conversely, why so many of those not so exposed do.18. Computers are becoming faster, more powerful, and more reliable, and so too are modems, the devices that allow two or more computers to share information over regular telephone lines.19. In virtually all types of tissue in every animal species, dioxin induces the production of enzymes that are the organism's attempt to metabolize, or render harmless, the chemical irritant.20. Using accounts of various ancient writers, scholars have painted a sketchy picture of the activities of an all-female cult that, perhaps as early as the sixth century BC, worshipped a goddess known in Latin as Bona Dea, "the good goddess."21. Paleontologists believe that fragments of a primate jawbone unearthed in Burma and estimated to be 40 to 44 million years old provide evidence of a crucial step along the evolutionary path that led to human beings.22. The end of the eighteenth century saw the emergence of prize-stock breeding, with individual bulls and cows receiving awards, fetching unprecedented prices, and exciting enormous interest whenever they were put on show.23. Of all the possible disasters that threaten American agriculture, the possibility of an adverse change in climate is probably the most difficult to analyze.24. For members of the seventeenth-century Ashanti nation in Africa, animal-hide shields with wooden frames were essential items of military equipment, protecting warriors against enemy arrows and spears.25. The golden crab of the Gulf of Mexico has not been fished commercially in great numbers, primarily because it lives at great depths-2,500 to 3,000 feet down.26. Galileo was convinced that natural phenomena, as manifestations of the laws of physics, would appear the same to someone on the deck of a ship moving smoothly and uniformly through the water as to a person standing on land.27. Health officials estimate that 35 million Africans are in danger of contracting trypanosomiasis, or "African sleeping sickness," a parasitic disease spread by the bites of tsetse flies.28. Beyond the immediate cash flow crisis that the museum faces, its survival depends on whether it can broaden its membership and leave its cramped quarters for a site where it can store and exhibit its more than 12,000 artifacts.29. Along with the drop in producer prices announced yesterday, the strong retail sales figures released today seem to indicate that the economy, although growing slowly, is not nearing a recession.30. An inventory equal to 90 days sales is as much as even the strongest businesses carry, and then only as a way to anticipate higher prices or ensure31. Egyptians are credited with having pioneered embalming methods as long ago as 2650 BC.32. The Commerce Department announced that the economy grew during the second quarter ata 7.5 percent annual rate, while inflation eased when it might have been expected to rise.33. Although schistosomiasis is not often fatal, it is so debilitating that it has become an economic drain on many developing countries.34. Efforts to equalize the funds available to school districts, a major goal of education reformers and many states in the 1970's, have not significantly reduced the gap that exists between the richest and poorest districts.35. Federal authorities involved in the investigation have found that local witnesses are difficult to locate, reticent, and suspicious of strangers.36. In 1527 King Henry VIII sought to have his marriage to Queen Catherine annulled so that he could marry Anne Boleyn.37. In one of the bloodiest battles of the Civil War, fought at Sharpsburg, Maryland, on September 17, 1862, four times as many Americans were killed as would later be killed on the beaches of Normandy during D-Day.38. Dr. Tonegawa won the Nobel Prize for discovering how the body can constantly change its genes to fashion a seemingly unlimited number of antibodies, each targeted specifically at an invading microbe or foreign substance.39. Scientists have recently discovered what could be the largest and oldest living organism on Earth, a giant fungus that is an interwoven filigree of mushrooms and rootlike tentacles spawned by a single fertilized spore some 10,000 years ago and extending for more than 30 acres in the soil of a Michigan forest.40. The plot of The Bostonians centers on the rivalry that develops between Olive Chancellor, an active feminist, and Basil Ransom, her charming and cynical cousin, when they find themselves drawn to the same radiant young woman whose talent for public speaking has won her an ardent following.41. While larger banks can afford to maintain their own data-processing operations, many smaller regional and community banks are finding that the costs associated with upgrading data-processing equipment and with the development and maintenance of new products and technical staff are prohibitive.42. Quasars, at billions of light-years from Earth the most distant observable objects in the universe, are believed to be the cores of galaxies in an early stage of development.43. Five fledgling sea eagles left their nests in western Scotland this summer, bringing to 34 the number of wild birds successfully raised since transplants from Norway began in 1975.44. The automotive conveyor-belt system, which Henry Ford modeled after an assembly-line technique introduced by Ransom Olds, reduced the time required to assemble a Model T from a day and a half to 93 minutes.45. According to some analysts, the gains in the stock market reflect growing confidence that the economy will avoid the recession that many had feared earlier in the year and instead come in fora "soft landing," followed by a gradual increase in business activity.46. Long before it was fashionable to be an expatriate, and she remained in France during the Second World War as a performer and an intelligence agent for the Resistance.47. By providing such services as mortgages, home improvement loans, automobile loans, andfinancial advice, and by staying within the metropolitan areas, Acme Bank has become one of the most profitable savings banks in the nation.48. The report recommended that the hospital eliminate unneeded beds, consolidate expensive services, and use space in other hospitals.49. Many house builders offer rent-to-buy programs that enable a family with insufficient savings for a conventional down payment to move into new housing and to apply part of the rent to a purchase later.50. It can hardly be said that educators are at fault for not anticipating the impact of microcomputer technology: Alvin Toffler, one of the most prominent students of the future, did not even mention microcomputers in Future Shock, published in 1970.51. The Olympic Games helped to keep peace among the pugnacious states of the Greek world, for a sacred truce was proclaimed during the month of the festival.52. While all states face similar industrial waste problems, the predominant industries and the regulatory environment of each state obviously determine the types and amounts of waste produced, as well as the cost of disposal.53. Section 13(d) of the Securities Exchange Act of 1934 requires anyone who buys more than 5 percent of a company's stock to make a public disclosure of the purchase.54. When Congress reconvenes, some newly elected members from rural states will try to establish tighter restrictions on the amount of grain farmers will be allowed to grow and to encourage more aggressive sales of United States farm products overseas.55. Doctors generally agree that such factors as cigarette smoking, eating rich foods high in fats, and alcohol consumption not only do damage by themselves but also aggravate genetic predispositions toward certain diseases.56. In a plan to stop the erosion of East Coast beaches, the Army Corps of Engineers proposed building parallel to shore a breakwater of rocks that would rise six feet above the waterline and act as a buffer, absorbing the energy of crashing waves and protecting the beaches.57. Affording strategic proximity to the Strait of Gibraltar, Morocco was also of interest to the French throughout the first half of the twentieth century because they assumed that without it their grip on Algeria would never be secure.58. Once they had seen the report from the medical examiner, the investigators had no doubt that the body recovered from the river was that of the man who had attempted to escape from the state prison.59. His studies of ice-polished rocks in his Alpine homeland, far outside the range of present-day glaciers, led Louis Agassiz in 1837 to propose the concept of an age in which great ice sheets existed in what are now temperate areas.60. More and more in recent years, cities are stressing the arts as a means to qreater economic development and investing millions of dollars in cultural activities, despite strained municipal budgets and fading federal support.61. Since 1986 enrollments of African Americans, American Indians, and Hispanic Americans in full-time engineering programs in the United States have steadily increased, while the number of other students entering the field has fallen.62. A 1972 agreement between Canada and the United States reduced the amount of phosphates that municipalities are allowed to dump into the Great Lakes.63. A proposal has been made to trim the horns from rhinoceroses to discourage poachers; the question is whether tourists will continue to visit game parks to see rhinoceroses once the animals' horns have been trimmed.64. The technical term "pagination" refers to a process that allows editors, rather than printers, to assemble the page images that become the metal or plastic plates used in printing.65. The only way for growers to salvage frozen citrus is to have it quickly processed into juice concentrate before warmer weather returns and rots the fruit.66. Unlike a typical automobile loan, which requires a 15 to 20 percent down payment, a lease-loan does not require the buyer to make an initial deposit on the new vehicle.67. Defense attorneys have occasionally argued that their clients' misconduct stemmed from a reaction to something ingested, but if criminal or delinquent behavior is attributed to an allergy to some food, the perpetrators are in effect told that they are not responsible for their actions. 68. Many people, willing to admit that they lack computer skills or other technical skills, are disinclined to recognize that their analytical skills are weak.69. A report by the American Academy for the Advancement of Science has concluded that many of the currently uncontrolled dioxins to which North Americans are exposed come from the incineration of wastes.70. Displays of the aurora borealis, or "northern lights," can heat the atmosphere over the Arctic enough to affect the trajectories of ballistic missiles and induce electric currents that can cause blackouts in some areas and corrosion in north-south pipelines.71. The cameras of the Voyager II spacecraft detected six small, previously unseen moons circling Uranus, doubling to 12 the number of satellites now known to orbit the distant planet.72. Architects and stonemasons, the Maya built huge palace and temple clusters without the benefit of animal transport or the wheel.73. According to a recent poll, owning and living in a freestanding house on its own land is still a goal of a majority of young adults, as it was of earlier generations.74. Often visible as smog, ozone is formed in the atmosphere when hydrocarbons and nitrogen oxides, two major pollutants emitted by automobiles, react with sunlight.75. Salt deposits and moisture threaten to destroy the Mohenjo-Daro excavation in Pakistan, the site of an ancient civilization that flourished at the same time as the civilizations in the Nile delta and the river valleys of the Tigris and Euphrates.76. Never before had taxpayers confronted as many changes at once as they confronted in the Tax Reform Act of 1986.77. Even though the direct costs of malpractice disputes amounted to less than 1 percent of the $541 billion the nation spent on health care last year, doctors say fear of lawsuits plays a major role in health-care inflation.78. Visitors to the park have often looked up into the leafy canopy and seen monkeys sleeping on the branches, with arms and legs hanging like socks on a clothesline.79. The Parthenon was a church from 1204 until 1456, when Athens was taken by General Mohammed the Conqueror, the Turkish sultan, who established a mosque in the building and used the Acropolis as a fortress.80. New hardy varieties of rice show promise of producing high yields without the costly irrigation and application of commercial fertilizer that were required by earlier high-yielding varieties.81. In an effort to reduce their inventories, Italian vintners have cut prices; their wines are priced to sell, and they do.82. Senator Lasker has proposed legislation requiring employers to retain all older workers indefinitely or show just cause for dismissal.83. Most state constitutions now mandate that the state budget be balanced each year.84. Under the Safe Drinking Water Act, the Environ¬mental Protection Agency is required either to approve individual state plans for controlling the discharge of wastes into underground water or to force its own plan for states without adequate regulations.85. Dirt roads may evoke the bucolic simplicity of another century, but financially strained townships point out that dirt roads cost twice as much to maintain as paved roads do.86. Although early soap operas were first aired on evening radio in the 1920's, they were moved to the daytime hours in the 1930's when the evening schedule became crowded with comedians and variety shows.87. The energy source on Voyager 2 is not a nuclear reactor, in which atoms are actively broken apart, but rather a kind of nuclear battery that uses natural radioactive decay to produce power.88. The recent surge in the number of airplane flights has clogged the nation's air-traffic control system, leading to a 55 percent increase in delays at airports and prompting fears among some officials that safety is being compromised.89. Presenters at the seminar, one of whom is blind, will demonstrate adaptive equipment that allows visually impaired people to use computers.90. The peaks of a mountain range, acting like rocks in a streambed, produce ripples in the air flowing over them; the resulting flow pattern, with crests and troughs that remain stationary although the air that forms them is moving rapidly, is known as "standing waves."91. The Senate approved immigration legislation that would grant permanent residency to millions of aliens currently residing here and penalize employers who hire illegal aliens.92. Despite protests from some waste-disposal companies, state health officials have ordered that the levels of bacteria in seawater at popular beaches be measured and the results published.93. By a vote of 9 to 0, the Supreme Court awarded the Central Intelligence Agency broad discretionary powers enabling it to withhold from the public the identities of its sources of intelligence information.94. The Coast Guard is conducting tests to see whether pigeons can be trained to help find survivors of wrecks at sea.95. Unlike Schoenberg, whose 12-tone system dominated the music of the postwar period, Bartok founded no school and left behind only a handful of disciples.96. Ranked as one of the most important of Europe's young playwrights, Franz Xaver Kroetz haswritten 40 plays; his works-translated into more than 30 languages-are produced more often than those of any other contemporary German dramatist.97. Like the planets, the stars are in motion, some of them at tremendous speeds, but they are so far away from Earth that their apparent positions in the sky do not change enough for their movement to be observed during a single human lifetime.98. As rainfall an to decrease in the Southwest about the middle of the twelfth century, most of the Monument Valley Anasazi abandoned their homes to join other clans whose access to water was less limited.99. Just as reading Samuel Pepys's diary gives a student a sense of the seventeenth century-of its texture and psyche-so listening to Jane Freed’s guile less child narrator takes the operagoer inside turn-of-the-¬century Vienna.100. Bihar is India's poorest state, with an annual per capita income of $111, lower than that of the most impoverished countries of the world.101. El Nino, the periodic abnormal warming of the sea surface off Peru, is a phenomenon in which changes in the ocean and atmosphere combine to allow the warm water that has accumulated in the western Pacific to flow back to the east.102. In her book illustrations, which she carefully coordinated with her narratives, Beatrix Potter capitalized on her keen observation and love of the natural world.103. A newly developed jumbo rocket, which is expected to carry the United States into its next phase of space exploration, will be able to deliver a heavier load of instruments into orbit than the space shuttle can, and at a lower cost.104. Nuclear fusion is the force that powers the Sun, the stars, and hydrogen bombs, merging the nuclei of atoms rather than splitting them apart, as nuclear reactors do.105. Originally developed for detecting air pollutants, a technique called proton-induced X-ray emission, which can quickly analyze the chemical elements in 'almost any substance without destroying it, is finding uses in medicine, archaeology, and criminology.106. Among the objects found in the excavated temple were small terra-cotta effigies left by supplicants who were either asking the goddess Bona Dea's aid in healing physical and mental ills or thanking her for such help.107. In his research paper, Dr. Frosh, medical director of the Payne Whitney Clinic, distinguishes between mood swings, which may be violent without being grounded in mental disease, and genuine manic-depressive psychosis.108. The first decision for most tenants living in a building undergoing conversion to cooperative ownership is whether to sign a no-buy pledge with the other tenants.109. Published in Harlem, the Messenger was owned and edited by two young journalists, A. Philip Randolph, who would later make his reputation as a labor leader, and Chandler Owen. 110. In June of 1987, The Bridge of Trinquetaille, Vincent van Gogh's view of an iron bridge over the Rhone, was sold for $20.2 million, the second highest price ever paid for a painting at auction.111. A baby emerges from the darkness of the womb with a rudimentary sense of vision that would be rated about 20/500; an adult with such vision would be deemed legally blind.112. The Federal Reserve Board's reduction of interest rates on loans to financial institutions is both an acknowledgment of past economic trends and an effort to influence their future direction.113. The original building and loan associations were organized as limited life funds, whose members made monthly payments on their share and then took turns drawing subscriptions on the funds for home mortgages.114. Gall's hypothesis that different mental functions are localized in different parts of the brain is widely accepted today.115. George Sand (Aurore Lucile Dupin) was one of the first European writers to consider the rural poor legitimate subjects for literature and to portray them these with sympathy and respect in her novels.116. Out of America's fascination with all things antique has grown a market for bygone styles of furniture and fixtures that is bringing back the chaise lounge, the overstuffed sofa, and the claw-footed bathtub.117. New theories propose that catastrophic impacts of asteroids and comets may have caused reversals in the Earth's magnetic field, the onset of ice ages, the splitting apart of continents 80 million years ago, and great volcanic eruptions.118. Students in the metropolitan school district are so lacking in math skills that it will be difficult to absorb them into a city economy becoming ever more dependent on information-based industries.119. The decision by one of the nation's largest banks to admit to $3 billion in potential losses on foreign loans could mean less lending by commercial banks to developing countries and increased pressure on multigovernment lenders to supply the funds.120. It has been estimated that illiteracy costs the United States at least $20 billion a year in lost industrial output and tax revenues.121. A firm that specializes in the analysis of handwriting claims to be able, from a one-page writing sample, to assess more than 300 hundred personality traits, including enthusiasm, imagination, and ambition.122. More than 30 years ago Dr. Barbara McClintock, the Nobel Prize winner, reported that genes can "jump," like pearls moving mysteriously from one necklace to another.123. Holland spends a larger percentage of its gross national product on defending its coasts from rising seas than the United States does on military defense.124. Canadian scientists have calculated that every nine years a human being will be struck by a meteorite, while each year 16 buildings can be expected to sustain damage from such objects.125. Samuel Sewall, like other seventeenth-century colonists, viewed marriage as a property arrangement rather than an emotional bond based on romantic love.126. A wildlife expert predicts that the reintroduction of the caribou into northern Minnesota will fail if the density of the timber wolf population in that region is greater than one wolf for every 39 square miles.127. Found throughout Central and South America, the sloth hangs from trees by its long rubbery limbs, sleeping 15 hours a day and moving so infrequently that two species of algae grow on its coat and between its toes.128. Today, because of improvements in agricultural technology, the same amount of acreage produces twice as many apples as it did in 1910.129. Joan of Arc, a young Frenchwoman who claimed to be divinely inspired, turned the tide of English victories in her country by liberating the city of Orleans and persuaded Charles VII of France to claim his throne.130. As a result of medical advances, many people who might once have died in childhood of such infections as diphtheria, pneumonia, or rheumatic fever now live well into old age.131. Cajuns speak a dialect brought to southern Louisiana by the 4,000 Acadians who migrated there in 1755; their language is basically seventeenth-century French to which English, Spanish, and Italian words have been added.132. One view of the economy contends that a large drop in oil prices should eventually lead to a lowering of interest rates and of fears about inflation, a rally in stocks and bonds, and a weakening of the dollar.133. Although the term "psychopath" is popularly applied to an especially brutal criminal, in psychology it refers to someone who is apparently incapable of feeling compassion or the pangs of conscience.134. Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced sickness, sleeping on the job, and fatigue among shift workers while raising production efficiency in various industries.135. Spanning more than 50 years, Friedrich Muller's career began in an unpromising apprenticeship as a Sanskrit scholar and culminated in virtually every honor that European governments and learned societies could bestow.136. Joachim Raft and Giacomo Meyerbeer are examples of the kind of composer who receives popular acclaim while living, but whose reputation declines after death and never regains its former status.137. The company announced that its profits declined much less in the second quarter than analysts had expected and that its business would improve in the second half of the year. 138. The direction in which the Earth and the other solid planets-Mercury, Venus, and Mars-spin was determined by collisions with giant celestial bodies in the early history of the solar system.。
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Mon. Not. R. Astron. Soc. 000, 000–000 (0000)Printed 27 February 2008A (MN L TEX style file v2.2)FIGGS: Faint Irregular Galaxies GMRT Survey − Overview, observations and first resultsarXiv:0802.3982v1 [astro-ph] 27 Feb 2008Ayesha Begum1⋆ , Jayaram N. Chengalur2, I. D. Karachentsev3, M. E. Sharina3 and S. S. Kaisin3of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA, UK Centre for Radio Astrophysics, Post Bag 3, Ganeshkhind, Pune 411 007, India 3 Special Astrophysical Observatory, Nizhnii Arkhys 369167, Russia2 National 1 InstituteABSTRACTThe Faint Irregular Galaxies GMRT Survey (FIGGS) is a Giant Metrewave Radio Telescope (GMRT) based HI imaging survey of a systematically selected sample of extremely faint nearby dwarf irregular galaxies. The primary goal of FIGGS is to provide a comprehensive and statistically robust characterization of the neutral inter-stellar medium properties of faint, gas rich dwarf galaxies. The FIGGS galaxies represent the extremely low-mass end of the dwarf irregular galaxies population, with a median MB ∼ −13.0 and median HI mass of ∼ 3 × 107 M⊙ , extending the baseline in mass and luminosity space for a comparative study of galaxy properties. The HI data is supplemented with observations at other wavelengths. In addition, distances accurate to ∼ 10% are available for most of the sample galaxies. This paper gives an introduction to FIGGS, describe the GMRT observations and presents the first results from the HI observations. From the FIGGS data we confirm the trend of increasing HI to optical diameter ratio with decreasing optical luminosity; the median ratio of DHI /DHo for the FIGGS sample is 2.4. Further, on comparing our data with aperture synthesis surveys of bright spirals, we find at best marginal evidence for a decrease in average surface density with decreasing HI mass. To a good approximation the disks of gas rich galaxies, ranging over 3 orders of magnitude in HI mass, can be described as being drawn from a family with constant HI surface density. Key words: galaxies: dwarf – galaxies: kinematics and dynamics – radio lines: galaxies1 INTRODUCTION HI 21cm aperture synthesis observations of nearby spiral galaxies is a mature field with over three decades of history – probably something of the order of a thousand galaxies have already been imaged. However observers have tended to focus on bright (∼ L∗ ) galaxies with HI masses 109 M⊙ . HI observations of faint dwarf galaxies (MB −17) generally require comparatively long integration times, and such galaxies have hence not been studied in similar numbers. While there have been some systematic HI surveys of dwarf galaxies (Swaters 1999; Stil & Israel 2002), these e have generally been restricted to the brighter (MB < − 14) dwarfs. In hierarchical models of galaxy formation, nearby dwarf galaxies would, in some ways, be analogs of the primordial building blocks of large galaxies. A systematic HI survey of the faintest dwarf galaxies could provide data that would be useful for a di-verse range of studies, ranging from, for example, testing the predictions of cold dark matter models (e.g Simon & Geha (2007); Blanton et al. (2007)), checking if such systems could be the host population of quasar absorption line systems (e.g. Zwaan et al. (2005); Kanekar & Chengalur (2005)) etc. As the most chemically unevolved systems in the present-day galaxy population, the faintest dwarfs provide unique laboratories for understanding star formation and galaxy evolution in extreme environments, i.e. low metallicity, low dust content, low pressure, low shear, and low escape velocity (e.g. Ekta et al. (2006)). In this paper we describe and present the first results from a Giant Meterwave Radio Telescope (GMRT) based HI imaging study of faint dwarf galaxies − the Faint Irregular Galaxies GMRT Survey (FIGGS). The primary goal of FIGGS is to obtain high quality observations of the atomic ISM for a large, systematically selected sample of faint, gas rich, dwarf irregular (dIrr) galaxies. Our GMRT HI images are supplemented by single dish HI observations, HST V and I band images and ground based Hα images⋆E-mail:ayesha@2Begum et al.The FIGGS sample has a median MB ∼ −13 and a median HI mass ∼ 3×107 M⊙ , while spanning range of more than 100 in stellar light, gas mass and dynamical mass, and more than 4 in gas fraction. It can also be clearly seen that by focusing on fainter, lower mass galaxies than those observed in previous HI imaging studies, FIGGS bridges the transition to rotation dominated low mass spirals and provides a substantially extended baseline in mass and luminosity space for a comparative study of galaxy properties.from the 6-m BTA telescope. Additionally, the HII region abundances and Hα rotation curves are being obtained on the William Herschel Telescope (WHT), Isaac Newton Telescope (INT) telescopes on La Palma and 6-m Russian BTA telescope, respectively. This paper is organised as follows. In Section 2 we describe the design and the properties of the galaxy sample. The main science drivers for FIGGS are described in Section.3. The GMRT observations are described in Section 4 and the results of the survey are presented and discussed in Section 5.3 SCIENCE DRIVERS FOR FIGGS 2 FIGGS: SAMPLE DEFINITION AND PROPERTIES The Faint Irregular Galaxies GMRT Survey − FIGGS, is a large observing program aimed at providing a comprehensive and statistically robust characterisation of the neutral ISM properties of faint, gas rich, dwarf irregular galaxies using the Giant Metrewave Radio Telescope (GMRT). The FIGGS sample forms a subsample of the Karachentsev et al.(2004) catalog of galaxies within ∼ 10 Mpc. Specifically, the FIGGS sample consists of 65 faint dwarf irregular (dIrr)galaxies with: e (i) absolute blue magnitude, MB > − 14.5, (ii) HI flux integral > 1 Jy kms−1 e (iii) optical B band major axis > 1.0 arcmin. The sample choice was dictated by a balance between achieving the scientific goals described in Section.3 and the practical limitations of the observing time. We note that the above mentioned criterion on the optical B band major axis was not strictly followed in few cases. Some unusual, very faint dwarf galaxies, with optical B band major axis < 1 arcmin were still included in our sample, as they are interesting cases to study in detail in HI. Further, for some of the galaxies in the FIGGS sample, fresh estimates of the distance (obtained after our observations were complete) imply absolute magnitudes slightly larger than the cut off above. These galaxies have however been retained in the sample. Some properties (mainly derived from optical observations) of galaxies in the FIGGS sample are listed in Table 1. The columns are as follows: Column(1) the galaxy name, Column(2)&(3) the equatorial coordinates (J2000), Column(4) the absolute blue magnitude (corrected for galactic extinction), Column(5) the Holmberg diameter in arcmin, Column(6) the (B-V) colour, Column(7) the distance in Mpc, Column(8) the method used to measure the distance − from the tip of the red giant branch (rgb), from membership in a group with known distance (grp), from the Tully-Fisher relation (tf), and from the Hubble flow (h). Column(9) gives the group membership of the galaxy, Column(10) the inclination determined from optical photometry (and assuming an intrinsic thickness, qo =0.2) and Column(11) the reference for the (B-V) colour, and/or revised distance. The data presented in the Table 1 (except for the colour) is taken from Karachentsev et al. (2004) catalog, except that revised distances have been adopted, if available. As can be seen from the Table 1, tip of the red giant branch (rgb) distances (which are generally accurate to ∼ 10%) are available for most of the galaxies in our sample. Figure 1 shows the histogram of the absolute blue magnitude (MB ), distance, HI mass, and HI mass to light ratio (MHI /LB ) for the FIGGS sample, while Figure 2 compares the distributions of gas fraction, luminosity and dynamical mass of the FIGGS galaxies with that of existing samples of galaxies with HI aperture synthesis observations. The gas fraction and the dynamical masses for the FIGGS sample have been derived from the GMRT observations. The aim of FIGGS is to provide a large multi-wavelength database for a systematically selected sample of extremely faint dwarf irregular galaxies. As mentioned in Section 1, such a database could be used to address a diverse range of astrophysical questions. Rather than attempting to enumerate all of these, in this section, we describe in some detail a couple of key science drivers for the FIGGS survey. 3.1 Star formation and feedback in small galaxies One of the main goals of FIGGS is to use the HI interferometric images in conjunction with the optical data to study the interplay between the neutral ISM and star formation in the faintest, lowest mass, gas rich dIrr galaxies. The gravitational binding energy for very faint dwarf irregular galaxies is not much larger than the energy output from a few supernovae; consequently star formation in such galaxies could have a profound effect on the morphology and kinematics of the ISM of these systems. The FIGGS data will enable us to study the ISM of most of our sample galaxies at a linear resolution of ∼ 15 − 300 pc − i.e. comparable to the scales at which energy is injected into the ISM through supernova and stellar winds. FIGGS thus provide a unique opportunity to study the effects of feedback from star formation in low mass, gas rich galaxies, which in turn will allow us to understand the processes driving the evolution of these galaxies. For example, it has been suggested that star formation in dwarf galaxies occurs only above a constant threshold HI column density of NHI ∼ 1021 cm−2 (e.g. Skillman 1987; Taylor 1994). Such a threshold could be a consequence of disk dynamics (e.g. related to Toomre’s instability criterion; Kennicutt (1989)) or a consequence of some other physical process, e.g. self shielding or thermo-gravitational instability (Schaye (2004)). A preliminary study of a small subsample of FIGGS (Begum et al. (2006)) suggested that unlike brighter dwarfs, the faintest dwarf galaxies do not show well defined threshold density. A detailed comparison of Hα and UV images with HI column density maps for the FIGGS sample will allow us to definitively answer the issue of the existence of a threshold density in the faintest galaxies and also to check whether the recipes for star formation derived from larger galaxies (Kennicutt (1989)) continue to be valid at this mass regime. These are critical issues in hierarchical galaxy formation models. 3.2 Dark and visible matter in small galaxies The second major aim of this survey is to study the relation between dark and baryonic matter in the smallest known star forming galaxies. According to several models of galaxy formation and evolution, the first burst of star formation in dwarf galaxies below a critical halo circular velocity (∼100 kms−1 ) could lead to the loss of a significant fraction of baryons (e.g. Efstathiou 2000;FIGGS: Faint Irregular Galaxies GMRT SurveyTable 1. The FIGGS sample3Galaxyα (J2000) (h m s) 00 36 38.00 00 42 32.30 00 43 03.80 00 49 49.30 01 07 22.30 01 34 51.60 01 44 42.70 02 24 35.00 02 27 27.00 04 25 15.60 04 32 00.30 04 53 06.90 05 59 41.20 06 37 56.60 07 00 29.30 07 13 51.80 07 28 17.20 07 42 31.20 07 57 01.80 08 32 56.00 08 34 06.50 08 52 50.70 09 42 59.80 09 45 04.20 10 07 19.70 10 21 25.20 11 05 35.00 11 28 00.60 11 33 29.10 11 36 06.40 11 47 11.20 11 50 53.00 11 54 43.00 12 13 22.70 12 13 49.60 12 14 07.40 12 15 46.70 12 16 28.60 12 25 17.90 12 25 27.90 12 27 41.80 12 28 39.00 12 56 04.00 12 58 40.40 13 08 03.60 13 13 22.80 13 21 08.20 13 24 36.00 13 30 44.40 13 36 30.80 13 39 19.40 13 39 53.80 13 40 18.10 13 50 51.10 13 54 48.70 14 07 10.70 14 15 56.50 14 28 03.70 16 13 47.60 20 03 57.40δ (J2000) (◦ ′ ′′ ) − 32 34 28 +40 34 19 −22 15 01 −21 00 58 +16 41 02 +52 5 30 +27 17 16 +56 0 42 +57 29 16 +72 48 21 +63 36 50 +67 05 57 +73 25 39 −25 59 59 −04 12 30 +10 31 19 +40 46 13 +16 33 40 +14 23 27 +71 01 46 +66 10 45 +33 47 52 +33 15 52 +32 14 18 +10 21 44 +71 06 58 −01 51 49 +78 59 29 +49 14 17 +45 17 7 +43 40 19 +38 52 50 −33 33 29 +29 55 18 −38 13 53 +66 05 32 +52 23 15 +52 13 38 +26 42 53 +28 28 57 +43 29 38 +35 43 05 +03 48 41 +14 13 03 +46 49 41 +46 19 11 −31 31 45 −30 58 20 +54 54 36 −29 14 11 +24 46 33 +40 44 21 −28 53 40 +38 01 16 +35 50 15 +35 03 37 +23 03 19 −46 18 06 +54 22 16 −31 40 54MB (mag) −8.39 −12.23 −14.17 −12.5 −14.31 −12.42 −12.13 −13.35 −13.03 −14.06 −15.65 −11.85 −12.30 −14.46 −12.6 −14.90 −14.75 −14.29 −14.27 −11.49 −13.37 −12.76 −12.98 −13.15 −15.08 −11.83 −13.14 −14.03 −13.71 −13.13 −9.73 −13.52 −12.31 −15.30 −12.70 −14.06 −13.25 −12.27 −15.55 −12.59 −14.16 −13.53 −15.49 −12.11 −12.26 −12.70 −11.76 −11.96 −12.98 −13.3 −13.68 −13.03 −13.90 −13.17 −12.42 −9.55 −12.51 −11.83 −9.96 −13.69DHo (′ ) 0.6 1.1 3.2 2.1 2.2 0.9 1.6 1.7 2.2 2.6 2.0 1.4 1.0 2.0 2.0 1.8 1.8 0.9 1.5 1.3 1.6 2.0 1.3 0.9 1.9 1.5 1.7∗ 1.5∗ 1.6 1.7 0.6 3.5 1.1 1.0 1.4 1.9 1.8 1.1 1.0 1.5 4.2 2.2 1.4 2.2 1.0 1.6 1.3 1.3 2.0 1.2∗ 1.2 1.6 1.6 1.7 1.3 1.7 2.28 2.4∗ 1.2 1.3B-V (mag) − 0.47 0.4 0.32 0.52 0.43 0.42 − − 0.63 1.1 0.58 0.4 0.51 − 0.55 0.31 0.54 0.47 0.24 0.45 − 0.49 0.56 0.33 − − 0.38 0.41 0.37 0.36 0.38 0.23 0.4 0.41 0.4 0.4 0.29 0.45 0.4 0.59 0.41 0.24 0.32 0.38 0.32 − 0.4 0.45 0.49 0.51 0.46 − 0.31 0.42 0.4 0.28 − − 0.58Dist (Mpc) 1.66 6.3 4.9 3.34 4.5 3.73 7.2 3.0 3.0 3.9 3.01 3.34 4.6 4.2 1.69 6.96 7.8 7.62 7.5 3.55 3.56 7.7 6.9 6.7 5.6 3.96 7.4 4.3 3.9 3.0 4.5 2.6 5.2 13.0 3.2 5.4 4.9 4.21 12.8 6.3 2.5 4.43 17.4 2.1 4.5 4.2 5.22 4.6 2.6 5.25 4.27 3.1 4.4 3.24 3.2 1.9 2.5 3.6 1.86 7.83D estmGroupiopt (deg) 57 41 72 69 46 55 71 59 78 57 62 62 58 42 55 55 48 58 58 24 30 42 83 17 62 55 64 60 57 58 49 71 44 69 67 68 77 58 84 74 58 44 40 25 47 58 65 53 55 68 49 57 52 75 28 35 42 71 55 68RefSC 24 And IV DDO 226 DDO 6 UGC 685 KKH 6 KK 14 KKH 11 KKH 12 KK 41 UGCA 92 KK 44 KKH 34 E490-17 HIZSS003 UGC 3755 DDO 43 KK 65 UGC 4115 KDG 52 UGC 4459 KK 69 UGC 5186 UGC 5209 UGC 5456 HS 117 UGC 6145 UGC 6456 UGC 6541 NGC 3741 KK 109 DDO 99 E379-07 KK 127 E321-014 UGC 7242 CGCG 269-049 UGC 7298 UGC 7505 KK 144 DDO 125 UGC 7605 UGC 8055 GR 8 UGC 8215 DDO 167 KK 195 KK 200 UGC 8508 E444-78 UGC 8638 DDO 181 I4316 DDO 183 UGC 8833 KK 230 DDO 187 P51659 KKR 25 KK 246Sculptor grp(?) rgb rgb rgb rgb rgb N672 grp Mafeii grp Maffei grp rgb rgb rgb rgb rgb rgb rgb rgb rgb rgb rgb rgb N2683 grp h h rgb rgb h rgb rgb rgb rgb rgb rgb ComaI grp rgb rgb rgb rgb tf h rgb rgb tf rgb rgb rgb rgb rgb rgb rgb rgb rgb rgb rgb rgb rgb rgb rgb rgb rgbdistant Irr Field Sculptor Sculptor Field IC 342/Maffei N672 IC 342/Maffei IC 342/Maffei IC 342 IC 342/Maffei IC432 M81 Field Field Field Field Field Field M81 M81 N2638 Field Field Field Field Field M81 CVn I CVn I CVn I CVn I Cen A ComaI Cen A M81 CVn I CVn I ComaI CVn I CVn I CVn I Field Field CVn I CVn I M83 M83 CVn I M83 CVn I CVn I M83 CVn I CVn I Field Field Cen A Field Field18,19 1 1 1 13,17 132 3, 17 4 13 5 6,15 7 8 13 4 4 13 8 911 10 7 13 13 13 17 13 13,17 16 4 6 13 6 13 9 4 12, 17 12 13 6 13 13, 17 13 9 13 4 113, 17*: Optical diameter measured at 25.0 mag arcsec−2 .4Begum et al.Table 1. (continued) The FIGGS sampleGalaxyα (J2000) (h m s) 20 30 15.30 20 30 32.60 20 46 53.00 23 26 27.50 23 45 34.00δ (J2000) (◦ ′ ′′ ) +60 26 25 +60 21 13 −12 50 57 −32 23 26 +38 43 4MB (mag) −14.54 −13.72 −11.09 −12.94 −10.78DHo (′ ) 1.8 1.6 3.6 2.4 1.1B-V (mag) 0.91 0.37 0.24 0.42 0.21Dist (Mpc) 5.6 5.6 1.0 2.2 2.5D estmGroupiopt (deg) 62 66 62 38 58RefKK 250, UGC11583 KK 251 DDO 210 UGCA 438 KKH 98N6946 grp N6946 grp rgb rgb rgbN6946 N6946 Field Sculptor Field14 14 4 13 13References: 1-van Zee (2000) 2-Karachentsev et al. (1999) 3-Karachentsev et al. (1996) 4-Begum et al. (2006) 5-Parodi (2002) 6-Makarova (1999) 7-Taylor et al. (2005) 8-Makarova et al. (2002) 9-Hunter & Elmegreen (2006) 10-Bremnes et al. (2000) 11-Hopp & Schulte-Ladbeck (1995) 12-Bremnes et al. (1999) 13-Sharina et al. 2008 (in preparation) 14-Begum & Chengalur (2004b) 15-Tully et al. (2006) 16-Corbin et al. (2008) 17-Karachentsev et al. (2006) 18-Ferguson et al. (2000) 19-Chengalur et al. 2008 (in preparation)[A][B][C][D]Figure 1. The histogram of MB (panel [A]), distance (panel [B]), logarithm of the HI mass (panel [C]) and the HI mass to light ratio, MHI /LB (panel [D]) for the FIGGS sample.Dekel & Woo 2003). In fact, expulsion of gas because of energy input from supernovae has been postulated as a possible mechanism to produce dwarf elliptical galaxies from gas rich progenitors (e.g. Miralda-Escude & Rees (1997)). Although a complete expulsion of the ISM from galaxies has not been observed so far, expansive outward motions of the neutral gas in dwarf galaxies has been observed in at least two galaxies (viz. GR8, Begum & Chengalur 2003; NGC 625, Cannon et al. 2004). To test these models, high spatial resolution interferometric observations are crucial. The Tully-Fisher (TF) relation demonstrates the existence of a tight relation between dark and luminous matter in bright spiral galaxies. Mcgaugh et al. (2000) (see also McGaugh (2005)) showed that dwarf galaxies deviate from the TF relation defined by bright spirals, but that the relationship is restored if one works with the total baryonic mass instead of the luminosity, i.e. a “Baryonic Tully Fisher” (BTF) relation. The FIGGS sample, both because it extends well beyond the region of rotation dominated dwarfs and because accurate distances are known for a large subsample, forms a very interesting dataset for studying TF and BTF relations. Most of the past studies have been done using the HI global velocity widths from the single dish observations (Geha et al. 2006; Mcgaugh et al. 2000). While for the brighter galaxies W20 (the velocity width at 20% emission, after correction for random motions and instrumental broadening), is a good measure of the rotational velocity of the galaxy (Verheijen & Sancisi 2001); it is unclear if this would remain true in the case of faint dwarf galaxies, where random motions could be comparable to the peak rotational velocities (e.g. Begum et al. 2003; Begum & Chengalur 2004a). For such galaxies, it is important to accurately correct for the pressure support (“asymmetric drift” correction) for which one needs to knowboth the rotation curve as well as the distribution of the HI gas, both of which can only be obtained by interferometric observations such as in FIGGS. The FIGGS sample would thus allow us to concretely answer this question using actual observational data. The HI kinematics of FIGGS galaxies, in conjunction with the Hα rotation curves can be used to accurately determine the density distribution of the dark matter halos of faint galaxies. Since stars generally make a minor contribution to the total mass in the FIGGS galaxies, accurate kinematical studies can provide direct information on the density profiles of their dark matter halos with less uncertainties arising from the unknown stellar mass to light ratio. Cosmological simulations of hierarchical galaxy formation predict a “universal” cusped density core for the dark matter halos of galaxies (e.g. Navarro et al. 2004). On the other hand, observations of dIrr galaxies indicate a constant density core for their dark matter halos (e.g. Weldrake et al. 2003; de Blok et al. 2003); however this comparison remains controversial (e.g. van den Bosch & Swaters 2001; de Blok 2005). FIGGS would not only provide a large sample for such a comparison, but would also provide a data set that is less subject to uncertainties due to the unknown stellar mass to light ratio or large scale non circular motions due to bars or spiral arms.4 HI OBSERVATIONS AND DATA ANALYSIS For all the GMRT HI observations, the observing bandwidth of 1 MHz was divided into 128 spectral channels, yielding a spectral resolution of 7.81 kHz (velocity resolution of 1.65 km s−1 ). It is worth noting that this velocity resolution is ∼ 4 times bet-FIGGS: Faint Irregular Galaxies GMRT Survey5[A][B]Figure 2. The gas fraction of FIGGS galaxies (circles) plotted as a function of the absolute blue magnitude (left) and dynamical mass (right). FIGGS galaxies with TRGB distances are shown as solid circles, whereas the remaining FIGGS galaxies are shown as empty circles. The same quantity is also plotted for the galaxies in literature with interferometric HI maps. The gas fraction (fgas ) is defined as fgas = Mgas /(Mgas +M∗ ). Mgas , is computed by scaling the HI mass by 1.33 to account for the primordial He fraction. No correction is made for the molecular gas. To compute the stellar mass, M∗ , the stellar mass to light ratio in the B band (Γ∗ ) was derived from the observed (B-V) colour , using from the galaxy evolution models of Bell et al.(2003) and assuming a “diet” Salpeter IMF. Solid triangles are from McGaugh(2005), solid squares from Verheijen(2001), crosses from Swaters (1999) and empty triangles from Cˆ t´ et al.(2000). oe Note how the GMRT FIGGS sample extends the coverage of all three galaxy properties.0.00.51.01.5020040060005010040 5049[A]DECLINATION (J2000)40 49[B]DECLINATION (J2000)40 48 00[C]47 304848DECLINATION (J2000)00474746 304646004545 30454444004344 304342 07 28 35302520 15 10 RIGHT ASCENSION (J2000)050027 550007 28 30 25 20 15 10 RIGHT ASCENSION (J2000) 05 0007 28 2520 15 RIGHT ASCENSION (J2000)10Figure 3. The figure shows the integrated HI emission from one of the galaxy in FIGGS sample, DDO 43 at various resolutions viz. 46′′ × 42′′ (panel [A]), 32′′ × 21′′ (panel [B]) and 15′′ × 12′′ (panel [C]). The first contour level and contour separation for these resolutions are (1.3,12.2), (2.5,18.1) and (4.0,26.2), respectively, in units of 1019 cm−2 .ter than most earlier interferometric studies of such faint dwarf galaxies (e.g.Lo et al. (1993)). This high velocity resolution is crucial to detect large scale velocity gradients in the faintest dwarf galaxies (e.g. Begum et al. (2003); Begum & Chengalur (2004a)). For each observing run, absolute flux and bandpass calibration was done by observing one of the standard flux calibrators 3C48, 3C286and 3C147, at the start and end of the observations. For the sample galaxies with low LSR velocities, particular care was taken to choose a bandpass calibrator which does not have any absorption feature in the relevant velocity range. The phase calibration was done once every 30 min by observing a nearby VLA phase calibrator source.6Begum et al.Table 2. Parameters of the GMRT observationsGalaxyDate of ObservationsVelocity Coverage (km s−1 ) 257 − 469 189 − 401 51 − 263 −45 − 166 317 − 529 205 − 415 − 36− 176 −205 − 7 −152 − 60 −5 − 216 404 − 616 209 − 421 248 − 460 173 − 385 235 − 447 357 − 569 445 − 657 432 − 644 438 − 650 −143 − 69 634 − 846 −208 − 3 144 − 356 106 − 318 136 − 348 534 − 746 46.0 − 258 507 − 719 −37 − 174 210 − 422 377 − 589 89 − 301 204 − 416 512 − 724 112 − 324 57 − 269 460 − 672 381 − 593 −44 − 167 475 − 686 168 − 380 96 − 308 474 − 686 86 − 298 121 − 333 47 − 259 285 − 497 255 − 469 −243 − −32Time on Source (hours) 3.5 5.0 3.5 4.0 5.0 3.0 3.7 2.1 3.0 4.5 3.5 5.0 3.5 5.0 4.0 4.0 5.0 4.5 3.0 3.0 5.0 3.5 5.0 4.0 3.5 4.5 3.5 3.5 6.5 3.0 4.5 4.0 7.0 6.0 6.0 3.5 4.5 5.0 7.0 2.5 2.5 5.5 2.7 6.5 3.5 2.5 3.0 2.5 6.0synthesised Beam (arcsec2 ) 52×46, 26×21, 19×17 50×45, 26×21, 16×12 42×40, 36×25, 27×19 41×33, 30×20, 16×11 41×38, 28×24, 16×13 46×36, 21×14, 13×10 47×37, 32×26, 16×11 42×40, 26×21, 16×14 53×52, 31×22, 20×16 53×50, 34×27, 22×18 49×46, 35×25, 24×14 42×40, 28×25, 18×16 46×42, 32×21, 15×12 41×37, 27×25, 19×17 42×41, 34×26, 18×14 56×51, 42×35, 28×24 41×37, 27×24, 15×13 41×37, 27×24, 18×15 41×36, 34×25, 22×20 46×42 42×37, 34×27, 20×14 53×39, 23×20, 16×15 42×33, 28×23, 21×15 49×41, 27×21, 18×13 45×37, 28×23, 19×16 54×47, 33×24, 19×18 49×44 51×45, 28×18, 15×10 45×37, 27×23, 18×15 45×39, 28×27, 24×18 41×40, 28×24, 19×14 45×36, 31×22, 20×14 43×38, 29×24, 16×12 40×37, 27×25, 19×17 46×39, 28×22, 17×14 51×38, 29×23, 19×16 62×54, 30×24, 18×16 48×47, 32×23, 21×17 42×38, 32×24, 18×15 48×47, 26×21, 18×11 44×36, 25×17, 16×11 50×41, 26×21, 17×14 48×46, 26×20, 15×11 42×38, 31×24, 17×13 41×39, 30×25, 21×18 46×37, 30×25, 19×13 48×41, 26×20, 15×14 61×39, 36×21, 15×11 42×41, 32×28, 15×14Noise (mJy) 3.2, 2.4, 2.1 3.4, 1.7, 1.4 4.0, 3.5, 3.1 3.0, 2.6, 2.2 3.0, 2.5, 2.1 3.0, 2.1, 1.8 1.6, 1.3, 1.0 5.5, 4.2, 3.5 1.9, 1.3, 1.1 4.0, 2.8, 2.4 6.0, 5.8, 4.0 3.8, 3.0, 2.6 3.2, 2.6, 2.2 3.0, 2.3, 1.9 3.4, 3.2, 2.7 4.0, 3.0, 2.5 3.0, 2.2, 1.6 3.2, 2.6, 2.1 4.0, 3.2, 2.6 3.8 2.4, 2.0, 1.8 5.0, 3.4, 3.0 3.8, 3.0, 2.4 4.8, 3.5, 2.7 3.8, 3.0, 2.7 3.0, 2.0, 1.7 3.0 3.9, 2.7, 2.3 2.2, 1.9, 1.6 4.0, 3.2, 2.8 4.0, 3.2, 2.7 4.2, 3.8, 3.0 2.3, 2.0, 1.7 3.3, 2.7, 2.4 3.6, 2.7, 2.4 6.0, 4.7, 4.1 3.9, 2.7, 2.1 2.9, 2.1, 1.8 2.6, 2.2, 1.8 6.0, 4.0, 3.5 4.0, 2.6, 2.0 5.2, 3.4, 2.7 3.6, 2.8, 2.3 2.7, 2.0, 1.7 3.7, 2.8, 2.3 5.0, 4.1, 3.4 3.4, 2.6, 2.2 4.2, 3.5, 2.9 3.2, 2.7, 2.4Phase CalCont Noise (mJy) 1.5, 0.9 1.3, 0.8 1.9, 1.0 1.3, 0.8 1.6, 0.8 1.9, 0.9 1.6, 0.8 2.9, 1.8 1.3, 0.8 1.7, 0.9 2.4, 1.2 1.9, 1.0 1.6, 1.0 1.7, 0.9 1.8, 1.1 1.9, 1.3 1.5, 0.8 1.6, 0.9 1.9, 1.2 1.8, 1.1 1.4, 1.0 2.0, 1.2 2.2, 1.0 2.3, 1.2 2.0, 1.1 1.8, 1.1 1.7, 1.1 1.8, 0.9 1.4, 0.8 1.6, 1.1 1.8, 1.0 1.8, 1.2 1.5, 0.9 2.0, 1.2 2.1, 1.2 2.5, 1.3 2.2, 1.1 1.8, 0.9 1.5, 0.8 2.3, 1.6 1.7, 1.0 2.1, 1.2 1.9, 1.0 1.5, 0.9 2.0, 1.5 2.4, 1.5 1.9, 1.1 2.2, 1.2 2.1, 1.2DDO 226 DDO 6 UGC 685 KKH 6 KK 14 KKH 11 KKH 12 UGCA 92 KK 41 KKH 34 E490-17 UGC 3755 DDO 43 KK 65 UGC 4115 KK 69 UGC 5186 UGC 5209 UGC 5456 HS 117 UGC 6145 UGC 6456 UGC 6541 KK 109 DDO 99 E379-07 KK 127 E321-014 UGC 7242 UGC 7505 KK 144 DDO 125 UGC 7605 UGC 8055 UGC 8215 DDO 167 KK 195 KK 200 UGC 8508 E444-78 UGC 8638 DDO 181 I4316 DDO 183 UGC 8833 DDO 187 P51659 KK 246 KKH 988 July 2004 1 Feb 2004 18 June 2004 9 July 2004 19 June 2004 25 Nov 2004 16 July 2004 6 June 2005 8 July 2004 9 June 2004 17 June 2004 11 Jan 2004 16 Jan 2005 25 Nov 2004 10 July 2004 3 Jan 2005 26 Nov 2004 15 Jan 2005 9 July 2004 8 Aug 2005 11 Feb 2005 19 June 2004 29 Nov 2004 6 June 2005 30 June 2005 19 Jan 2005 9 July 2004 7 Oct 2005 3 Feb 2004 28 Nov 2004 12 July 2004 6 June 2005 1 Feb 2004 13 June 2005 29 Nov 2004 10 July 2004 4 Jan 2005 26 Nov 2004 31 Jan 2004 20 June 2004 9 July 2004 6 June 2005 7 Aug 2005 31 Jan 2004 16 June 2004 16 June 2004 14 Jan 2005 16 June 2004 10 July 20040025-260 0116-208 0204+152 0136+473 3C48 0110+565 0110+565 0410+769 0410+769 0410+769 0608-223 0745+101 0713+438 0738+177 0745+101 0741+312 0958+324 0958+324 1008+075 1035+564 1150-003 1435+760 1035+564 1227+365 1227+365 1154-350 1227+365 1154-350 1313+675 1227+365 1221+282 1227+365 1227+365 1254+116 1227+365 1227+365 1018-317 1316-336 1400+621 1316-336 1330+251 3C286 1316-336 1331+305 3C286 3C286 1316-336 1923-210 0029+349The GMRT data were reduced in the usual way using the standard tasks in classic AIPS. For each run, bad visibility points were edited out, after which the data were calibrated. The GMRT does not do online doppler tracking – any required doppler shifts have to be applied during the offline analysis. However, for all of the sample galaxies, the differential doppler shift over our observing interval was much less than the channel width, hence, there was no need to apply any offline correction. The GMRT has a hybrid configuration (Swarup et al. 1991) with 14 of its 30 antennas locatedin a central compact array with size ≈ 1 km (≈ 5 kλ at 21cm) and the remaining antennas distributed in a roughly “Y” shaped configuration, giving a maximum baseline length of ≈ 25 km (≈ 120 kλ at 21 cm). The baselines obtained from antennas in the central compact array are similar in length to those of the “D” array of the VLA, while the baselines between the arm antennas are comparable in length to the “B” array of the VLA. A single observation with the GMRT hence yields information on both large and small angular scales. Data cubes at a range of angular resolutions were made。