Tidally-induced Super Star Clusters in M82
高三宇宙奥秘英语阅读理解30题
高三宇宙奥秘英语阅读理解30题1<背景文章>Black holes are one of the most fascinating and mysterious phenomena in the universe. A black hole is formed when a massive star collapses at the end of its life. The gravitational pull of a black hole is so strong that nothing, not even light, can escape from it.The formation of a black hole begins with the collapse of a massive star. As the star runs out of fuel, it can no longer support its own weight and begins to collapse. The collapse continues until the star reaches a critical density, at which point it becomes a black hole.Black holes have several unique characteristics. One of the most notable is their event horizon, which is the boundary beyond which nothing can escape. Another characteristic is their intense gravitational field, which can distort the space and time around them.Black holes can have a significant impact on the surrounding celestial bodies. They can attract and swallow nearby stars and planets, and their gravitational pull can also affect the orbits of other celestial bodies.Scientists are still working to understand black holes better. They use a variety of tools and techniques, such as telescopes and computer simulations, to study these mysterious objects. Despite significant progressin recent years, there is still much that we don't know about black holes.1. What is a black hole formed by?A. A small star collapsing.B. A massive star collapsing.C. A planet collapsing.D. A moon collapsing.答案：B。
天文学会专业词汇【4】
Sagittarius dwarf ⼈马矮星系 Sagittarius dwarf galaxy ⼈马矮星系 Sagittarius galaxy ⼈马星系 Saha equation 沙哈⽅程 Sakigake 〈先驱〉空间探测器 Saturn-crossing asteroid 越⼟⼩⾏星 Saturnian ringlet ⼟星细环 Saturnshine ⼟星反照 scroll 卷滚 Sculptor group ⽟夫星系群 Sculptor Supercluster ⽟夫超星系团 Sculptor void ⽟夫巨洞 secondary crater 次级陨击坑 secondary resonance 次共振 secular evolution 长期演化 secular resonance 长期共振 seeing management 视宁度控管 segregation 层化 selenogony ⽉球起源学 separatrice 分界 sequential estimation 序贯估计 sequential processing 序贯处理 serendipitous X-ray source 偶遇 X 射线源 serendipitous γ-ray source 偶遇γ射线源 Serrurier truss 赛路⾥桁架 shell galaxy 壳星系 shepherd satellite 牧⽺⽝卫星 shock temperature 激波温度 silicon target vidicon 硅靶光导摄象管 single-arc method 单弧法 SIRTF, Space Infrared Telescope 空间红外望远镜 Facility slitless spectroscopy ⽆缝分光 slit spectroscopy 有缝分光 slow pulsar 慢转脉冲星 SMM, Solar Maximum MIssion 太阳极⼤使者 SMT, Submillimeter Telescope 亚毫⽶波望远镜 SOFIA, Stratospheric Observatory for 〈索菲雅〉机载红外望远镜 Infrared Astronomy soft γ-ray burst repeater 软γ暴复现源 soft γ repeater （ SGR ）软γ射线复现源 SOHO, Solar and Heliospheric 〈索贺〉太阳和太阳风层探测器 Observatory solar circle 太阳圈 solar oscillation 太阳振荡 solar pulsation 太阳脉动 solar-radiation pressure 太阳辐射压 solar-terrestrial environment ⽇地环境 solitary 孤⼦性 soliton star 孤⼦星 South Galactic Cap 南银冠 South Galactic Pole 南银极 space density profile 空间密度轮廓 space geodesy 空间⼤地测量 space geodynamics 空间地球动⼒学 Spacelab 空间实验室 spatial mass segregation 空间质量分层 speckle masking 斑点掩模 speckle photometry 斑点测光 speckle spectroscopy 斑点分光 spectral comparator ⽐长仪 spectrophotometric distance 分光光度距离 spectrophotometric standard 分光光度标准星 spectroscopic period 分光周期 specular density 定向密度 spherical dwarf 椭球矮星系 spin evolution ⾃旋演化 spin period ⾃旋周期 spin phase ⾃旋相位 spiral 旋涡星系 spiral arm tracer ⽰臂天体 Spoerer minimum 斯珀勒极⼩ spotted star 富⿊⼦恒星 SST, Spectroscopic Survey Telescope 分光巡天望远镜 standard radial-velocity star 视向速度标准星 standard rotational-velocity star ⾃转速度标准星 standard velocity star 视向速度标准星 starburst 星暴 starburst galaxy 星暴星系 starburst nucleus 星暴 star complex 恒星复合体 star-formation activity 产星活动 star-formation burst 产星暴 star-formation efficiency （ SFE ）产星效率 star-formation rate 产星率 star-formation region 产星区 star-forming region 产星区 starpatch 星斑 static property 静态特性 statistical orbit-determination 统计定轨理论 theory steep-spectrum radio quasar 陡谱射电类星体 stellar environment 恒星环境 stellar halo 恒星晕 stellar jet 恒星喷流 stellar speedometer 恒星视向速度仪 stellar seismology 星震学 Stokes polarimetry 斯托克斯偏振测量 strange attractor 奇异吸引体 strange star 奇异星 sub-arcsec radio astronomy 亚⾓秒射电天⽂学 Subaru Telescope 昴星望远镜 subcluster 次团 subclustering 次成团 subdwarf B star B 型亚矮星 subdwarf O star O 型亚矮星 subgiant branch 亚巨星⽀ submilliarcsecond optical astrometry 亚毫⾓秒光波天体测量 submillimeter astronomy 亚毫⽶波天⽂ submillimeter observatory 亚毫⽶波天⽂台 submillimeter photometry 亚毫⽶波测光 submillimeter space astronomy 亚毫⽶波空间天⽂ submillimeter telescope 亚毫⽶波望远镜 submillisecond optical pulsar 亚毫秒光学脉冲星 submillisecond pulsar 亚毫秒脉冲星 submillisecond radio pulsar 亚毫秒射电脉冲星 substellar object 亚恒星天体 subsynchronism 亚同步 subsynchronous rotation 亚同步⾃转 Sunflower galaxy （ M 63 ）葵花星系 sungrazer comet 掠⽇彗星 supercluster 超星团; 超星系团 supergalactic streamer 超星系流状结构 supergiant molecular cloud （ SGMC ）超巨分⼦云 superhump 长驼峰 superhumper 长驼峰星 supermaximum 长极⼤ supernova rate 超新星频数、超新星出现率 supernova shock 超新星激波 superoutburst 长爆发 superwind galaxy 超级风星系 supporting system ⽀承系统 surface activity 表⾯活动 surface-brightness profile ⾯亮度轮廓 surface-channel CCD 表⾯型 CCD SU Ursae Majoris star ⼤熊 SU 型星 SWAS, Submillimeter Wave Astronomy 亚毫⽶波天⽂卫星 Satallite symbiotic binary 共⽣双星 symbiotic Mira 共⽣刍藁 symbiotic nova 共⽣新星 synthetic-aperture radar 综合孔径雷达 systemic velocity 质⼼速度TAMS, terminal-age main sequence 终龄主序 Taurus molecular cloud （ TMC ）⾦⽜分⼦云 TDT, terrestrial dynamical time 地球⼒学时 television guider 电视导星器 television-type detector 电视型探测器 Tenma 〈天马〉X 射线天⽂卫星 terrestrial reference system 地球参考系 tetrad 四元基 thermal background 热背景辐射 thermal background radiation 热背景辐射 thermal pulse 热脉冲 thermonuclear runaway 热核暴涨 thick-disk population 厚盘族 thinned CCD 薄型 CCD third light 第三光源 time-signal station 时号台 timing age 计时年龄 tomograph 三维结构图 toner 调⾊剂 torquetum ⾚基黄道仪 TRACE, Transition Region and Coronal 〈TRACE〉太阳过渡区和⽇冕 Explorer 探测器 tracker 跟踪器 transfer efficiency 转移效率 transition region line 过渡区谱线 trans-Nepturnian object 海外天体 Trapezium cluster 猎户四边形星团 triad 三元基 tri-dimensional spectroscopy 三维分光 triquetum 三⾓仪 tuning-fork diagram ⾳叉图 turnoff age 拐点年龄 turnoff mass 拐点质量 two-dimensional photometry ⼆维测光 two-dimensional spectroscopy ⼆维分光 UKIRT, UK Infrared Telescope Facility 联合王国红外望远镜 UKST, UK Schmidt Telescope 联合王国施密特望远镜 ultracompact H Ⅱ region 超致密电离氢区 ultradeep-field observation 特深天区观测 ultraluminous galaxy 超⾼光度星系 ultrametal-poor star 特贫⾦属星 Ulysses 〈尤利西斯〉太阳探测器 unseen component 未见⼦星 upper tangent arc 上正切晕弧 unnumbered asteroid 未编号⼩⾏星 Uranian ring 天王星环 Ursa Major group ⼤熊星群 Ursa Minorids ⼩熊流星群 Vainu Bappu Observatory 巴普天⽂台 variable-velocity star 视向速度变星 vectorial astrometry ⽮量天体测量 vector-point diagram ⽮点图 Vega 〈维佳〉⾏星际探测器 Vega phenomenon 织⼥星现象 velocity variable 视向速度变星 Venera 〈⾦星〉号⾏星际探测器 very strong-lined giant, VSL giant 甚强线巨星 very strong-lined star, VSL star 甚强线星 video astronomy 录象天⽂ viewfinder 寻星镜 Viking 〈海盗〉号⽕星探测器 virial coefficient 位⼒系数 virial equilibrium 位⼒平衡 virial radius 位⼒半径 virial temperature 位⼒温度 virtual phase CCD 虚相 CCD visible arm 可见臂 visible component 可见⼦星 visual star 光学星 VLT, Very Large Telescope 甚⼤望远镜 void 巨洞 Vondrak method 冯德拉克⽅法 Voyager 〈旅⾏者〉号⾏星际探测器 VSOP, VLBI Space Observatory 空间甚长基线⼲涉测量 Programme 天⽂台计划 wave-front sensor 波前传感器 weak-line T Tauri star 弱线⾦⽜ T 型星 Wesselink mass 韦塞林克质量 WET, Whole Earth Telescope 全球望远镜 WHT, William Herschel Telescope 〈赫歇尔〉望远镜 wide-angle eyepiece ⼴⾓⽬镜 wide binary galaxy 远距双重星系 wide visual binary 远距⽬视双星 Wild Duck cluster （ M 11 ）野鸭星团 Wind 〈风〉太阳风和地球外空磁层 探测器 WIRE, Wide-field Infrared Explorer 〈WIRE〉⼴⾓红外探测器 WIYN Telescope, Wisconsin-Indiana- 〈WIYN〉望远镜 Yale-NOAO Telescope WR nebula, Wolf-Rayet nebula WR 星云 Wyoming Infrared Telescope 怀俄明红外望远镜 xenobiology 外空⽣物学 XMM, X-ray Mirror Mission X 射线成象望远镜 X-ray corona X 射线冕 X-ray eclipse X 射线⾷ X-ray halo X 射线晕 XTE, X-ray Timing Explorer X 射线计时探测器 yellow straggler 黄离散星 Yohkoh 〈阳光〉太阳探测器 young stellar object （ YSO ）年轻恒星体 ZAHB, zero-age horizontal branch 零龄⽔平⽀ Zanstra temperature 赞斯特拉温度 ZZ Ceti star 鲸鱼 ZZ 型星 γ-ray burster （ GRB ）γ射线暴源 γ-ray line γ谱线 γ-ray line astronomy γ谱线天⽂ γ-ray line emission γ谱线发射 ζ Aurigae binary 御夫ζ型双星 ζ Aurigae variable 御夫ζ型变星absolute energy distribution 绝对能量分布 abundance effect 丰度效应 angular diameter—redshift relation ⾓径—红移关系 asteroid astrometry ⼩⾏星天体测量 bursting pulsar （ GRO J1744-28 ）暴态脉冲星 Caliban 天卫⼗七 canonical Big Bang 典型⼤爆炸 Cepheid binary 造⽗双星 CH anomaly CH 反常 chromospheric plage ⾊球谱斑 circumnuclear star-forming ring 核周产星环 circumstellar astrophysics 星周天体物理 CN anomaly CN 反常 colliding-wind binary 星风互撞双星 collisional de-excitation 碰撞去激发 collisional ionization 碰撞电离 collision line broadening 碰撞谱线致宽 Compton loss 康普顿耗损 continuous opacity 连续不透明度 coronagraphic camera ⽇冕照相机 coronal active region ⽇冕活动区 cosmic-ray exposure age 宇宙线曝射法年龄 count—magnitude relation 计数—星等关系 Cousins color system 卡曾斯颜⾊系统 dating method 纪年法 DDO color system DDO 颜⾊系统 deep sky object 深空天体 deep sky phenomena 深空天象 dense star cluster 稠密星团 diagnostics 诊断法 dissociative recombination 离解复合 Doppler line broadening 多普勒谱线致宽 epicyclic orbit 本轮轨道 extragalactic background 河外背景 extragalactic background radiation 河外背景辐射 flare particle emission 耀斑粒⼦发射 flare physics 耀斑物理 Fm star Fm 星 focal plane spectrometer 焦⾯分光计 focusing X-ray telescope 聚焦 X 射线望远镜 Friedmann time 弗⾥德曼时间 galactic chimney 星系通道 Galactic chimney 银河系通道 gas relention age ⽓体变异法年龄 Gauss line profile ⾼斯谱线轮廓 GCR （ Galactic cosmic rays ）银河系宇宙线 Geneva color system ⽇内⽡颜⾊系统 global oscilletion 全球振荡 GW-Vir instability strip 室⼥ GW 不稳定带 Highly Advanced Laboratory for 〈HALCA〉通讯和天⽂⾼新空间 Communications and Astronomy 实验室 （ HALCA ） Hipparcos catalogue 依巴⾕星表 Hobby-Eberly Telescope （ HET ）〈HET〉⼤型拼镶镜⾯望远镜 Hoyle—Narlikar cosmology 霍伊尔—纳⾥卡宇宙学 Hubble Deep Field （ HDF ）哈勃深空区 human space flight 载⼈空间飞⾏、⼈上天 imaging spectrograph 成象摄谱仪 infrared camera 红外照相机 infrared luminosity 红外光度 infrared polarimetry 红外偏振测量 in-situ acceleration 原位加速 intercept age 截距法年龄 inverse Compton limit 逆康普顿极限 isochron age 等龄线法年龄 Johnson color system 约翰逊颜⾊系统 K giant variable （ KGV ） K 型巨变星 kinetic equilibrium 运动学平衡 large-scale beam ⼤尺度射束 large-scale jet ⼤尺度喷流 limb polarization 临边偏振 line-profile variable 谱线轮廓变星 long term fluctuation 长期起伏 Lorentz line profile 洛伦兹谱线轮廓 magnetic arm 磁臂 Mars globe ⽕星仪 massive black hole ⼤质量⿊洞 mean extinction coefficient 平均消光系数 mean luminosity density 平均光度密度 microwave storm 微波噪暴 Milli-Meter Array （ MMA ）〈MMA〉毫⽶波射电望远镜阵 molecular maser 分⼦微波激射、分⼦脉泽 moving atmosphere 动态⼤⽓ neutrino loss rate 中微⼦耗损率 non-linear astronomy ⾮线性天⽂ non-standard model ⾮标准模型 passband width 带宽 P Cygni type star 天鹅 P 型星 Perseus chimney 英仙通道 planetary companion 似⾏星伴天体 plateau phase 平台阶段 primordial abundance 原始丰度 protobinary system 原双星 proto-brown dwarf 原褐矮星 quiescent galaxy 宁静星系 radiation transport 辐射转移 radio-intermediate quasar 中介射电类星体 random peculiar motion 随机本动 relative energy distribution 相对能量分布 RGU color system RGU 颜⾊系统 ringed barred galaxy 有环棒旋星系 ringed barred spiral galaxy 有环棒旋星系 rise phase 上升阶段 Rossi X-ray Timing Explorer （ RXTE ）〈RXTE〉X 射线时变探测器 RQPNMLK color system RQPNMLK 颜⾊系统 Scheuer—Readhead hypothesis 朔伊尔—⾥德⿊德假说 Serpens molecular cloud 巨蛇分⼦云 soft X-ray transient （ SXT ）软 X 射线暂现源 solar dynamo 太阳发电机 solar global parameter 太阳整体参数 solar neighbourhood 太阳附近空间 spectral catalogue 光谱表 spectral duplicity 光谱成双性 star-formation process 产星过程 star-forming phase 产星阶段 Stroemgren color system 颜⾊系统 Sub-Millimeter Array （ SMA ）〈SMA〉亚毫⽶波射电望远镜阵 superassociation 超级星协 supermassive black hole 特⼤质量⿊洞 supersoft X-ray source 超软 X 射线源 super-star cluster 超级星团 Sycorax 天卫⼗七 symbiotic recurrent nova 共⽣再发新星 synchrotron loss 同步加速耗损 time dilation 时间扩展 tired-light model 光线⽼化宇宙模型 tremendous outburst amplitude 巨爆幅 tremendous outburst amplitude dwarf 巨爆幅矮新星 nova （ TOAD ） Tycho catalogue 第⾕星表 UBV color system UBV 颜⾊系统 UBVRI color system UBVRI 颜⾊系统 ultraviolet luminosity 紫外光度 unrestricted orbit ⽆限制性轨道 uvby color system uvby 颜⾊系统 VBLUW color system VBLUW 颜⾊系统 Venus globe ⾦星仪 Vilnius color system 维尔纽斯颜⾊系统 Virgo galaxy cluster 室⼥星系团 VLBA （ Very Long Baseline Array ）〈VLBA〉甚长基线射电望远镜阵 Voigt line profile 佛克特谱线轮廓 VRI color system VRI 颜⾊系统 Walraven color system 沃尔拉⽂颜⾊系统 waning crescent 残⽉ waning gibbous 亏凸⽉ waxing crescent 娥眉⽉ waxing gibbous 盈凸⽉ WBVR color system WBVR 颜⾊系统 Wood color system 伍德颜⾊系统 zodiacal light photometry 黄道光测光 11-year solar cycle 11 年太阳周 α Cygni variable 天津四型变星 δ Doradus variable 剑鱼δ型变星。
黑洞的准正模式(quasinormal modes)
Quasi-Normal Modes of Stars and Black HolesKostas D.KokkotasDepartment of Physics,Aristotle University of Thessaloniki,Thessaloniki54006,Greece.kokkotas@astro.auth.grhttp://www.astro.auth.gr/˜kokkotasandBernd G.SchmidtMax Planck Institute for Gravitational Physics,Albert Einstein Institute,D-14476Golm,Germany.bernd@aei-potsdam.mpg.dePublished16September1999/Articles/Volume2/1999-2kokkotasLiving Reviews in RelativityPublished by the Max Planck Institute for Gravitational PhysicsAlbert Einstein Institute,GermanyAbstractPerturbations of stars and black holes have been one of the main topics of relativistic astrophysics for the last few decades.They are of partic-ular importance today,because of their relevance to gravitational waveastronomy.In this review we present the theory of quasi-normal modes ofcompact objects from both the mathematical and astrophysical points ofview.The discussion includes perturbations of black holes(Schwarzschild,Reissner-Nordstr¨o m,Kerr and Kerr-Newman)and relativistic stars(non-rotating and slowly-rotating).The properties of the various families ofquasi-normal modes are described,and numerical techniques for calculat-ing quasi-normal modes reviewed.The successes,as well as the limits,of perturbation theory are presented,and its role in the emerging era ofnumerical relativity and supercomputers is discussed.c 1999Max-Planck-Gesellschaft and the authors.Further information on copyright is given at /Info/Copyright/.For permission to reproduce the article please contact livrev@aei-potsdam.mpg.de.Article AmendmentsOn author request a Living Reviews article can be amended to include errata and small additions to ensure that the most accurate and up-to-date infor-mation possible is provided.For detailed documentation of amendments, please go to the article’s online version at/Articles/Volume2/1999-2kokkotas/. Owing to the fact that a Living Reviews article can evolve over time,we recommend to cite the article as follows:Kokkotas,K.D.,and Schmidt,B.G.,“Quasi-Normal Modes of Stars and Black Holes”,Living Rev.Relativity,2,(1999),2.[Online Article]:cited on<date>, /Articles/Volume2/1999-2kokkotas/. The date in’cited on<date>’then uniquely identifies the version of the article you are referring to.3Quasi-Normal Modes of Stars and Black HolesContents1Introduction4 2Normal Modes–Quasi-Normal Modes–Resonances7 3Quasi-Normal Modes of Black Holes123.1Schwarzschild Black Holes (12)3.2Kerr Black Holes (17)3.3Stability and Completeness of Quasi-Normal Modes (20)4Quasi-Normal Modes of Relativistic Stars234.1Stellar Pulsations:The Theoretical Minimum (23)4.2Mode Analysis (26)4.2.1Families of Fluid Modes (26)4.2.2Families of Spacetime or w-Modes (30)4.3Stability (31)5Excitation and Detection of QNMs325.1Studies of Black Hole QNM Excitation (33)5.2Studies of Stellar QNM Excitation (34)5.3Detection of the QNM Ringing (37)5.4Parameter Estimation (39)6Numerical Techniques426.1Black Holes (42)6.1.1Evolving the Time Dependent Wave Equation (42)6.1.2Integration of the Time Independent Wave Equation (43)6.1.3WKB Methods (44)6.1.4The Method of Continued Fractions (44)6.2Relativistic Stars (45)7Where Are We Going?487.1Synergism Between Perturbation Theory and Numerical Relativity487.2Second Order Perturbations (48)7.3Mode Calculations (49)7.4The Detectors (49)8Acknowledgments50 9Appendix:Schr¨o dinger Equation Versus Wave Equation51Living Reviews in Relativity(1999-2)K.D.Kokkotas and B.G.Schmidt41IntroductionHelioseismology and asteroseismology are well known terms in classical astro-physics.From the beginning of the century the variability of Cepheids has been used for the accurate measurement of cosmic distances,while the variability of a number of stellar objects(RR Lyrae,Mira)has been associated with stel-lar oscillations.Observations of solar oscillations(with thousands of nonradial modes)have also revealed a wealth of information about the internal structure of the Sun[204].Practically every stellar object oscillates radially or nonradi-ally,and although there is great difficulty in observing such oscillations there are already results for various types of stars(O,B,...).All these types of pulsations of normal main sequence stars can be studied via Newtonian theory and they are of no importance for the forthcoming era of gravitational wave astronomy.The gravitational waves emitted by these stars are extremely weak and have very low frequencies(cf.for a discussion of the sun[70],and an im-portant new measurement of the sun’s quadrupole moment and its application in the measurement of the anomalous precession of Mercury’s perihelion[163]). This is not the case when we consider very compact stellar objects i.e.neutron stars and black holes.Their oscillations,produced mainly during the formation phase,can be strong enough to be detected by the gravitational wave detectors (LIGO,VIRGO,GEO600,SPHERE)which are under construction.In the framework of general relativity(GR)quasi-normal modes(QNM) arise,as perturbations(electromagnetic or gravitational)of stellar or black hole spacetimes.Due to the emission of gravitational waves there are no normal mode oscillations but instead the frequencies become“quasi-normal”(complex), with the real part representing the actual frequency of the oscillation and the imaginary part representing the damping.In this review we shall discuss the oscillations of neutron stars and black holes.The natural way to study these oscillations is by considering the linearized Einstein equations.Nevertheless,there has been recent work on nonlinear black hole perturbations[101,102,103,104,100]while,as yet nothing is known for nonlinear stellar oscillations in general relativity.The study of black hole perturbations was initiated by the pioneering work of Regge and Wheeler[173]in the late50s and was continued by Zerilli[212]. The perturbations of relativistic stars in GR werefirst studied in the late60s by Kip Thorne and his collaborators[202,198,199,200].The initial aim of Regge and Wheeler was to study the stability of a black hole to small perturbations and they did not try to connect these perturbations to astrophysics.In con-trast,for the case of relativistic stars,Thorne’s aim was to extend the known properties of Newtonian oscillation theory to general relativity,and to estimate the frequencies and the energy radiated as gravitational waves.QNMs werefirst pointed out by Vishveshwara[207]in calculations of the scattering of gravitational waves by a Schwarzschild black hole,while Press[164] coined the term quasi-normal frequencies.QNM oscillations have been found in perturbation calculations of particles falling into Schwarzschild[73]and Kerr black holes[76,80]and in the collapse of a star to form a black hole[66,67,68]. Living Reviews in Relativity(1999-2)5Quasi-Normal Modes of Stars and Black Holes Numerical investigations of the fully nonlinear equations of general relativity have provided results which agree with the results of perturbation calculations;in particular numerical studies of the head-on collision of two black holes [30,29](cf.Figure 1)and gravitational collapse to a Kerr hole [191].Recently,Price,Pullin and collaborators [170,31,101,28]have pushed forward the agreement between full nonlinear numerical results and results from perturbation theory for the collision of two black holes.This proves the power of the perturbation approach even in highly nonlinear problems while at the same time indicating its limits.In the concluding remarks of their pioneering paper on nonradial oscillations of neutron stars Thorne and Campollataro [202]described it as “just a modest introduction to a story which promises to be long,complicated and fascinating ”.The story has undoubtedly proved to be intriguing,and many authors have contributed to our present understanding of the pulsations of both black holes and neutron stars.Thirty years after these prophetic words by Thorne and Campollataro hundreds of papers have been written in an attempt to understand the stability,the characteristic frequencies and the mechanisms of excitation of these oscillations.Their relevance to the emission of gravitational waves was always the basic underlying reason of each study.An account of all this work will be attempted in the next sections hoping that the interested reader will find this review useful both as a guide to the literature and as an inspiration for future work on the open problems of the field.020406080100Time (M ADM )-0.3-0.2-0.10.00.10.20.3(l =2) Z e r i l l i F u n c t i o n Numerical solutionQNM fit Figure 1:QNM ringing after the head-on collision of two unequal mass black holes [29].The continuous line corresponds to the full nonlinear numerical calculation while the dotted line is a fit to the fundamental and first overtone QNM.In the next section we attempt to give a mathematical definition of QNMs.Living Reviews in Relativity (1999-2)K.D.Kokkotas and B.G.Schmidt6 The third and fourth section will be devoted to the study of the black hole and stellar QNMs.In thefifth section we discuss the excitation and observation of QNMs andfinally in the sixth section we will mention the more significant numerical techniques used in the study of QNMs.Living Reviews in Relativity(1999-2)7Quasi-Normal Modes of Stars and Black Holes 2Normal Modes–Quasi-Normal Modes–Res-onancesBefore discussing quasi-normal modes it is useful to remember what normal modes are!Compact classical linear oscillating systems such asfinite strings,mem-branes,or cavitiesfilled with electromagnetic radiation have preferred time harmonic states of motion(ωis real):χn(t,x)=e iωn tχn(x),n=1,2,3...,(1) if dissipation is neglected.(We assumeχto be some complex valuedfield.) There is generally an infinite collection of such periodic solutions,and the“gen-eral solution”can be expressed as a superposition,χ(t,x)=∞n=1a n e iωn tχn(x),(2)of such normal modes.The simplest example is a string of length L which isfixed at its ends.All such systems can be described by systems of partial differential equations of the type(χmay be a vector)∂χ∂t=Aχ,(3)where A is a linear operator acting only on the spatial variables.Because of thefiniteness of the system the time evolution is only determined if some boundary conditions are prescribed.The search for solutions periodic in time leads to a boundary value problem in the spatial variables.In simple cases it is of the Sturm-Liouville type.The treatment of such boundary value problems for differential equations played an important role in the development of Hilbert space techniques.A Hilbert space is chosen such that the differential operator becomes sym-metric.Due to the boundary conditions dictated by the physical problem,A becomes a self-adjoint operator on the appropriate Hilbert space and has a pure point spectrum.The eigenfunctions and eigenvalues determine the periodic solutions(1).The definition of self-adjointness is rather subtle from a physicist’s point of view since fairly complicated“domain issues”play an essential role.(See[43] where a mathematical exposition for physicists is given.)The wave equation modeling thefinite string has solutions of various degrees of differentiability. To describe all“realistic situations”,clearly C∞functions should be sufficient. Sometimes it may,however,also be convenient to consider more general solu-tions.From the mathematical point of view the collection of all smooth functions is not a natural setting to study the wave equation because sequences of solutionsLiving Reviews in Relativity(1999-2)K.D.Kokkotas and B.G.Schmidt8 exist which converge to non-smooth solutions.To establish such powerful state-ments like(2)one has to study the equation on certain subsets of the Hilbert space of square integrable functions.For“nice”equations it usually happens that the eigenfunctions are in fact analytic.They can then be used to gen-erate,for example,all smooth solutions by a pointwise converging series(2). The key point is that we need some mathematical sophistication to obtain the “completeness property”of the eigenfunctions.This picture of“normal modes”changes when we consider“open systems”which can lose energy to infinity.The simplest case are waves on an infinite string.The general solution of this problem isχ(t,x)=A(t−x)+B(t+x)(4) with“arbitrary”functions A and B.Which solutions should we study?Since we have all solutions,this is not a serious question.In more general cases, however,in which the general solution is not known,we have to select a certain class of solutions which we consider as relevant for the physical problem.Let us consider for the following discussion,as an example,a wave equation with a potential on the real line,∂2∂t2χ+ −∂2∂x2+V(x)χ=0.(5)Cauchy dataχ(0,x),∂tχ(0,x)which have two derivatives determine a unique twice differentiable solution.No boundary condition is needed at infinity to determine the time evolution of the data!This can be established by fairly simple PDE theory[116].There exist solutions for which the support of thefields are spatially compact, or–the other extreme–solutions with infinite total energy for which thefields grow at spatial infinity in a quite arbitrary way!From the point of view of physics smooth solutions with spatially compact support should be the relevant class–who cares what happens near infinity! Again it turns out that mathematically it is more convenient to study all solu-tions offinite total energy.Then the relevant operator is again self-adjoint,but now its spectrum is purely“continuous”.There are no eigenfunctions which are square integrable.Only“improper eigenfunctions”like plane waves exist.This expresses the fact that wefind a solution of the form(1)for any realωand by forming appropriate superpositions one can construct solutions which are “almost eigenfunctions”.(In the case V(x)≡0these are wave packets formed from plane waves.)These solutions are the analogs of normal modes for infinite systems.Let us now turn to the discussion of“quasi-normal modes”which are concep-tually different to normal modes.To define quasi-normal modes let us consider the wave equation(5)for potentials with V≥0which vanish for|x|>x0.Then in this case all solutions determined by data of compact support are bounded: |χ(t,x)|<C.We can use Laplace transformation techniques to represent such Living Reviews in Relativity(1999-2)9Quasi-Normal Modes of Stars and Black Holes solutions.The Laplace transformˆχ(s,x)(s>0real)of a solutionχ(t,x)isˆχ(s,x)= ∞0e−stχ(t,x)dt,(6) and satisfies the ordinary differential equations2ˆχ−ˆχ +Vˆχ=+sχ(0,x)+∂tχ(0,x),(7) wheres2ˆχ−ˆχ +Vˆχ=0(8) is the homogeneous equation.The boundedness ofχimplies thatˆχis analytic for positive,real s,and has an analytic continuation onto the complex half plane Re(s)>0.Which solutionˆχof this inhomogeneous equation gives the unique solution in spacetime determined by the data?There is no arbitrariness;only one of the Green functions for the inhomogeneous equation is correct!All Green functions can be constructed by the following well known method. Choose any two linearly independent solutions of the homogeneous equation f−(s,x)and f+(s,x),and defineG(s,x,x )=1W(s)f−(s,x )f+(s,x)(x <x),f−(s,x)f+(s,x )(x >x),(9)where W(s)is the Wronskian of f−and f+.If we denote the inhomogeneity of(7)by j,a solution of(7)isˆχ(s,x)= ∞−∞G(s,x,x )j(s,x )dx .(10) We still have to select a unique pair of solutions f−,f+.Here the information that the solution in spacetime is bounded can be used.The definition of the Laplace transform implies thatˆχis bounded as a function of x.Because the potential V vanishes for|x|>x0,the solutions of the homogeneous equation(8) for|x|>x0aref=e±sx.(11) The following pair of solutionsf+=e−sx for x>x0,f−=e+sx for x<−x0,(12) which is linearly independent for Re(s)>0,gives the unique Green function which defines a bounded solution for j of compact support.Note that for Re(s)>0the solution f+is exponentially decaying for large x and f−is expo-nentially decaying for small x.For small x however,f+will be a linear com-bination a(s)e−sx+b(s)e sx which will in general grow exponentially.Similar behavior is found for f−.Living Reviews in Relativity(1999-2)K.D.Kokkotas and B.G.Schmidt 10Quasi-Normal mode frequencies s n can be defined as those complex numbers for whichf +(s n ,x )=c (s n )f −(s n ,x ),(13)that is the two functions become linearly dependent,the Wronskian vanishes and the Green function is singular!The corresponding solutions f +(s n ,x )are called quasi eigenfunctions.Are there such numbers s n ?From the boundedness of the solution in space-time we know that the unique Green function must exist for Re (s )>0.Hence f +,f −are linearly independent for those values of s .However,as solutions f +,f −of the homogeneous equation (8)they have a unique continuation to the complex s plane.In [35]it is shown that for positive potentials with compact support there is always a countable number of zeros of the Wronskian with Re (s )<0.What is the mathematical and physical significance of the quasi-normal fre-quencies s n and the corresponding quasi-normal functions f +?First of all we should note that because of Re (s )<0the function f +grows exponentially for small and large x !The corresponding spacetime solution e s n t f +(s n ,x )is therefore not a physically relevant solution,unlike the normal modes.If one studies the inverse Laplace transformation and expresses χas a com-plex line integral (a >0),χ(t,x )=12πi +∞−∞e (a +is )t ˆχ(a +is,x )ds,(14)one can deform the path of the complex integration and show that the late time behavior of solutions can be approximated in finite parts of the space by a finite sum of the form χ(t,x )∼N n =1a n e (αn +iβn )t f +(s n ,x ).(15)Here we assume that Re (s n +1)<Re (s n )<0,s n =αn +iβn .The approxi-mation ∼means that if we choose x 0,x 1, and t 0then there exists a constant C (t 0,x 0,x 1, )such that χ(t,x )−N n =1a n e (αn +iβn )t f +(s n ,x ) ≤Ce (−|αN +1|+ )t (16)holds for t >t 0,x 0<x <x 1, >0with C (t 0,x 0,x 1, )independent of t .The constants a n depend only on the data [35]!This implies in particular that all solutions defined by data of compact support decay exponentially in time on spatially bounded regions.The generic leading order decay is determined by the quasi-normal mode frequency with the largest real part s 1,i.e.slowest damping.On finite intervals and for late times the solution is approximated by a finite sum of quasi eigenfunctions (15).It is presently unclear whether one can strengthen (16)to a statement like (2),a pointwise expansion of the late time solution in terms of quasi-normal Living Reviews in Relativity (1999-2)11Quasi-Normal Modes of Stars and Black Holes modes.For one particular potential(P¨o schl-Teller)this has been shown by Beyer[42].Let us now consider the case where the potential is positive for all x,but decays near infinity as happens for example for the wave equation on the static Schwarzschild spacetime.Data of compact support determine again solutions which are bounded[117].Hence we can proceed as before.Thefirst new point concerns the definitions of f±.It can be shown that the homogeneous equation(8)has for each real positive s a unique solution f+(s,x)such that lim x→∞(e sx f+(s,x))=1holds and correspondingly for f−.These functions are uniquely determined,define the correct Green function and have analytic continuations onto the complex half plane Re(s)>0.It is however quite complicated to get a good representation of these func-tions.If the point at infinity is not a regular singular point,we do not even get converging series expansions for f±.(This is particularly serious for values of s with negative real part because we expect exponential growth in x).The next new feature is that the analyticity properties of f±in the complex s plane depend on the decay of the potential.To obtain information about analytic continuation,even use of analyticity properties of the potential in x is made!Branch cuts may occur.Nevertheless in a lot of cases an infinite number of quasi-normal mode frequencies exists.The fact that the potential never vanishes may,however,destroy the expo-nential decay in time of the solutions and therefore the essential properties of the quasi-normal modes.This probably happens if the potential decays slower than exponentially.There is,however,the following way out:Suppose you want to study a solution determined by data of compact support from t=0to some largefinite time t=T.Up to this time the solution is–because of domain of dependence properties–completely independent of the potential for sufficiently large x.Hence we may see an exponential decay of the form(15)in a time range t1<t<T.This is the behavior seen in numerical calculations.The situation is similar in the case ofα-decay in quantum mechanics.A comparison of quasi-normal modes of wave equations and resonances in quantum theory can be found in the appendix,see section9.Living Reviews in Relativity(1999-2)K.D.Kokkotas and B.G.Schmidt123Quasi-Normal Modes of Black HolesOne of the most interesting aspects of gravitational wave detection will be the connection with the existence of black holes[201].Although there are presently several indirect ways of identifying black holes in the universe,gravitational waves emitted by an oscillating black hole will carry a uniquefingerprint which would lead to the direct identification of their existence.As we mentioned earlier,gravitational radiation from black hole oscillations exhibits certain characteristic frequencies which are independent of the pro-cesses giving rise to these oscillations.These“quasi-normal”frequencies are directly connected to the parameters of the black hole(mass,charge and angu-lar momentum)and for stellar mass black holes are expected to be inside the bandwidth of the constructed gravitational wave detectors.The perturbations of a Schwarzschild black hole reduce to a simple wave equation which has been studied extensively.The wave equation for the case of a Reissner-Nordstr¨o m black hole is more or less similar to the Schwarzschild case,but for Kerr one has to solve a system of coupled wave equations(one for the radial part and one for the angular part).For this reason the Kerr case has been studied less thoroughly.Finally,in the case of Kerr-Newman black holes we face the problem that the perturbations cannot be separated in their angular and radial parts and thus apart from special cases[124]the problem has not been studied at all.3.1Schwarzschild Black HolesThe study of perturbations of Schwarzschild black holes assumes a small per-turbation hµνon a static spherically symmetric background metricds2=g0µνdxµdxν=−e v(r)dt2+eλ(r)dr2+r2 dθ2+sin2θdφ2 ,(17) with the perturbed metric having the formgµν=g0µν+hµν,(18) which leads to a variation of the Einstein equations i.e.δGµν=4πδTµν.(19) By assuming a decomposition into tensor spherical harmonics for each hµνof the formχ(t,r,θ,φ)= mχ m(r,t)r Y m(θ,φ),(20)the perturbation problem is reduced to a single wave equation,for the func-tionχ m(r,t)(which is a combination of the various components of hµν).It should be pointed out that equation(20)is an expansion for scalar quantities only.From the10independent components of the hµνonly h tt,h tr,and h rr transform as scalars under rotations.The h tθ,h tφ,h rθ,and h rφtransform asLiving Reviews in Relativity(1999-2)13Quasi-Normal Modes of Stars and Black Holes components of two-vectors under rotations and can be expanded in a series of vector spherical harmonics while the components hθθ,hθφ,and hφφtransform as components of a2×2tensor and can be expanded in a series of tensor spher-ical harmonics(see[202,212,152]for details).There are two classes of vector spherical harmonics(polar and axial)which are build out of combinations of the Levi-Civita volume form and the gradient operator acting on the scalar spherical harmonics.The difference between the two families is their parity. Under the parity operatorπa spherical harmonic with index transforms as (−1) ,the polar class of perturbations transform under parity in the same way, as(−1) ,and the axial perturbations as(−1) +11.Finally,since we are dealing with spherically symmetric spacetimes the solution will be independent of m, thus this subscript can be omitted.The radial component of a perturbation outside the event horizon satisfies the following wave equation,∂2∂t χ + −∂2∂r∗+V (r)χ =0,(21)where r∗is the“tortoise”radial coordinate defined byr∗=r+2M log(r/2M−1),(22) and M is the mass of the black hole.For“axial”perturbationsV (r)= 1−2M r ( +1)r+2σMr(23)is the effective potential or(as it is known in the literature)Regge-Wheeler potential[173],which is a single potential barrier with a peak around r=3M, which is the location of the unstable photon orbit.The form(23)is true even if we consider scalar or electromagnetic testfields as perturbations.The parameter σtakes the values1for scalar perturbations,0for electromagnetic perturbations, and−3for gravitational perturbations and can be expressed asσ=1−s2,where s=0,1,2is the spin of the perturbingfield.For“polar”perturbations the effective potential was derived by Zerilli[212]and has the form V (r)= 1−2M r 2n2(n+1)r3+6n2Mr2+18nM2r+18M3r3(nr+3M)2,(24)1In the literature the polar perturbations are also called even-parity because they are characterized by their behavior under parity operations as discussed earlier,and in the same way the axial perturbations are called odd-parity.We will stick to the polar/axial terminology since there is a confusion with the definition of the parity operation,the reason is that to most people,the words“even”and“odd”imply that a mode transforms underπas(−1)2n or(−1)2n+1respectively(for n some integer).However only the polar modes with even have even parity and only axial modes with even have odd parity.If is odd,then polar modes have odd parity and axial modes have even parity.Another terminology is to call the polar perturbations spheroidal and the axial ones toroidal.This definition is coming from the study of stellar pulsations in Newtonian theory and represents the type offluid motions that each type of perturbation induces.Since we are dealing both with stars and black holes we will stick to the polar/axial terminology.Living Reviews in Relativity(1999-2)K.D.Kokkotas and B.G.Schmidt14where2n=( −1)( +2).(25) Chandrasekhar[54]has shown that one can transform the equation(21)for “axial”modes to the corresponding one for“polar”modes via a transforma-tion involving differential operations.It can also be shown that both forms are connected to the Bardeen-Press[38]perturbation equation derived via the Newman-Penrose formalism.The potential V (r∗)decays exponentially near the horizon,r∗→−∞,and as r−2∗for r∗→+∞.From the form of equation(21)it is evident that the study of black hole perturbations will follow the footsteps of the theory outlined in section2.Kay and Wald[117]have shown that solutions with data of compact sup-port are bounded.Hence we know that the time independent Green function G(s,r∗,r ∗)is analytic for Re(s)>0.The essential difficulty is now to obtain the solutions f±(cf.equation(10))of the equations2ˆχ−ˆχ +Vˆχ=0,(26) (prime denotes differentiation with respect to r∗)which satisfy for real,positives:f+∼e−sr∗for r∗→∞,f−∼e+r∗x for r∗→−∞.(27) To determine the quasi-normal modes we need the analytic continuations of these functions.As the horizon(r∗→∞)is a regular singular point of(26),a representation of f−(r∗,s)as a converging series exists.For M=12it reads:f−(r,s)=(r−1)s∞n=0a n(s)(r−1)n.(28)The series converges for all complex s and|r−1|<1[162].(The analytic extension of f−is investigated in[115].)The result is that f−has an extension to the complex s plane with poles only at negative real integers.The representation of f+is more complicated:Because infinity is a singular point no power series expansion like(28)exists.A representation coming from the iteration of the defining integral equation is given by Jensen and Candelas[115],see also[159]. It turns out that the continuation of f+has a branch cut Re(s)≤0due to the decay r−2for large r[115].The most extensive mathematical investigation of quasi-normal modes of the Schwarzschild solution is contained in the paper by Bachelot and Motet-Bachelot[35].Here the existence of an infinite number of quasi-normal modes is demonstrated.Truncating the potential(23)to make it of compact support leads to the estimate(16).The decay of solutions in time is not exponential because of the weak decay of the potential for large r.At late times,the quasi-normal oscillations are swamped by the radiative tail[166,167].This tail radiation is of interest in its Living Reviews in Relativity(1999-2)。
2017-2018学年第一学期海淀高三语文期末练习(附答案)
海淀区高三年级第一学期期末练习语文2018.1一、本大题共8小题，共24分。
阅读下面的材料，完成1－8题。
材料一目前，被誉为“中国天眼”的500米口径球面射电望远镜，还未正式运行就新发现6颗脉冲星。
中国科学家在北京发布了它取得的首批成果。
“中国天眼”是中国“十一五”重大科技基础设施之一，基于选址方法、索网主动反射面、柔性索结合并联机器人的馈源支撑这三项中国自主创新技术，它突破了射电望远镜工程的极限。
在未来可预见的二三十年内，它将是我们这个星球最先进、最灵敏的射电望远镜。
人类迄今已发现2500余颗脉冲星。
但在“中国天眼”问世前，中国望远镜从未捕捉到新的脉冲星。
事实证明，重大的科学突破离不开科研仪器的进步。
世界各国相继认识到大科学装置在国家创新能力建设中的重要地位，中国也在不断兴建重器。
包括“中国天眼”在内，仅中国科学院目前运行和在建的重大科技基础设施就有23个。
2013年国务院印发的《国家重大科技基础设施建设中长期规划(2012—2030年)》对能源、生命、天文等7个科学领域进行了系统【甲】bùshǔ。
中国科学院国家天文台台长严俊认为，“中国天眼”调试进展超过预期、打破大型同类设备调试周期的国际惯例，并有系统的科学产出，这得益于【乙】卓．有成效的早期科学规划和人才储备。
从最初不到5人的研究小组扩大到上百人团队，“中国天眼”凭借国内100多家参建单位的力量，由跟踪模仿发展到集成创新。
发布会当日，人们自发为“中国天眼”之父，项目总工程师兼首席科学家南仁东先生默哀。
2017年9月15日，在“中国天眼”落成近一周年之际，曾为之奔波奋斗的南先生【丙】溘．然长逝。
当年他毅然舍弃高薪，回国就任中国科学院北京天文台副台长。
1993年国际无线电科学联盟大会上，外国科学家们提出要建造新一代射电望远镜，以接受更多来自外太空的讯息。
南先生跟同事们说：“咱们也建一个吧！”从那时起，一干就是二十多年。
如今“中国天眼”新发现的脉冲星【丁】yìyì生辉，人们感慨它“足以告慰老南”。
梅西耶天体110个介绍M22
梅西耶天体110个介绍M22
M22 ⼈马座球状星团
abraham ihle在1665年发现的
⾚经18 : 36.4时:分⾚纬-23 : 54 度:分距离1.04万光年
这可能是第⼀个被发现的球状星团。
m22是个⾮常显著的天体。
距离我们10400光年，是离我们最近的球状星团之⼀。
在这个距离上，它的32'的⾓直径，⽐满⽉的视直径稍⼤，对应的⼤⼩约为97光年；⽬视时，仍有⼤约17'。
它的亮度⽐武仙座球状星团m13还明亮，因此北半球纬度不⾼的观测者可以⽤⾁眼看到这⼀天体，尽管shapley和pease在这个巨⼤的恒星蜂巢内数出了7万颗恒星，只有相当少量的32颗变星被认证出来，其中的⼀颗长周期薴藁增⼆型变星很可能不是星团的成员星。
星团中最明亮的恒星⼤约为11等。
恒星散布在⼤约200光年直径的区域内，以每秒149km的速度远离我们⽽去。
夜空中最亮的星：科学家发现超亮星系
夜空中最亮的星：科学家发现超亮星系
佚名
【期刊名称】《科学大众：小诺贝儿》
【年(卷),期】2016(0)7
【摘要】英国剑桥大学的天文学家日前在银河中发现一个超亮星系，它属于矮星系，其亮度足有16万个太阳那么耀眼。
【总页数】1页(P17-17)
【关键词】矮星系;科学家;夜空;英国剑桥大学;天文学家;银河;太阳
【正文语种】中文
【中图分类】P157
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4.夜空中最亮的星——献给联通公司疫情阻击战中社区昼夜执勤的战友们 [J], 宫明
5.中国青年女科学家奖得主陈雪飞：夜空中最亮的星 [J],
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2022年新高考模拟卷语文5（原卷版）解析
2022年新高考模拟卷语文5（原卷版）解析如果说高考是一场战役，那么头脑就是抢，学识就是子弹，铃声就是信号，考卷就是目标，答题就是拼杀，成绩就是胜利。
高考之战在即，让我们扛起抢，子弹上膛，聆听信号，冲向目标，英勇拼杀，多取最后的胜利！下面是高考店铺为大家编辑整理的“2022年高考语文模拟卷（新高考专用）（解析版）”此文本仅供参考，欢迎阅读。
一、非连续性文本阅读阅读下面的文字，完成各题材料一：“中国天眼”身在法地，但在科学家眼中，它心系深空，是一座“天空实验室”。
到现在为止，应该没有天文学家上过太空，但他们却是最了解宇宙的一群人，靠的是什么？不少人小时候索试过用曝光的胶片观看日食，还有动手能力更强的，用两个放大镜自制过光学望远镜。
望远镜就是天文学家了解宇宙的必备工具。
但射电望远镜不同于人们熟悉的光学望远镜、它不能直接成像，而是抓取目标的无线电信号，用数据说话。
天文学家利用“天眼”开展工作，有点类似移动靶射击运动，需要不断地选取目标、瞄准目标射击、分析结果。
据北京大学教授、中科院国家天文台研究员李柯伽介绍，第一步要考虑望远镜频率是否合适、灵敏度是否足够、目标是不是在可视范围内，以便确定观测源的坐标，形成观测列表。
第二步是望远镜控制部门执行观测。
如何精确控制“天眼”瞄准动辄光年之外的目标？简单地说，一是通过天体坐标计算出望远镜所需的“姿态”，二是驱动电机控制望远镜的“姿态”。
因为地球在不停自转和公转，这样的观测比移动靶射击复杂得多，要不断地修正望远镜的位置，不断地瞄准目标，并确保一直命中靶心。
第三步是通过编程来分析数据。
外表安静的“天眼”，内心澎湃，每秒最高传输数据38G。
海量的数据，基本没有手动分析的可能，所以天文学家都是“程序员”，用大数据手段实现天地“连线”。
前辈科学家发现的物理定律，我们在物理实验室里做实验，结果都能验证定律为真。
在“天空实验室”里呢？那可不一定。
天文学跟物理学密不可分，大尺度时空结构、宇宙演化、高能天体（如黑洞、脉冲星等）都是以广义相对论为重要理论基础的。
太空双胞胎：同卵星系中神秘的双星
太空双胞胎：同卵星系中神秘的双星1.引言太空中隐藏着无数神秘和奇妙的现象，其中之一就是同卵星系中的双星。
双星是由两颗恒星组成的系统，它们紧密地相互环绕，并以共同的中心引力维持着它们的运动。
近年来，太空探索使得我们对这些同卵星系有了更深入的了解，其中最有趣的一个例子就是“太空双胞胎”。
2.太空双胞胎的背景2015年，美国国家航空航天局（NASA）进行了一项名为“太空双胞胎”的研究，该研究的目标是比较在太空和地球上生活了一年的双胞胎，发现在太空中生活对身体和心理的影响。
这对双胞胎中的一位名叫斯科特·凯利，是一名资深宇航员，而他的兄弟马克·凯利则留在地球上作为对照。
3.研究方法与结果斯科特·凯利在国际空间站度过了将近一年的时间，而他的兄弟马克·凯利则在地球上作为对照进行观察。
在这期间，科学家们对两位双胞胎进行了各种体征和生理指标的监测，包括基因表达、心理状态、骨骼密度等等。
4.生物学变化通过比较两位双胞胎的基因表达数据，科学家们发现斯科特·凯利在太空中的基因表达出现了一些与地球上不同的变化。
其中最引人注目的是免疫系统的变化，斯科特的免疫系统在太空中表现出一定的抑制状态，这对于长期太空探索有着重要的意义。
5.骨骼和肌肉的适应由于失重环境的影响，斯科特·凯利在太空中的骨骼和肌肉质量都出现了明显的减少。
这是因为在失重环境中，肌肉和骨骼没有承受重力的压力，导致它们逐渐变得弱化。
这也是未来长期太空任务面临的一个重要问题，如何维持宇航员的骨骼和肌肉健康是一个需要解决的难题。
6.心理和认知方面的变化除了生物学上的变化，斯科特·凯利还经历了一些心理和认知方面的变化。
在太空中，宇航员需要适应封闭、孤独和高压力的环境，这对心理状态和认知能力都提出了很大的挑战。
斯科特在太空中表现出一定的情绪波动和注意力不集中的情况，这也提醒我们在未来的太空任务中需要关注宇航员的心理健康。
溴到硼酸酯
Materials Chemistry C
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Cite this: J. Mater. Chem. C, 2015, 3, 861
However, these oligouorene functionalized oligomers may suffer from the unwanted long wavelength emission under long-term device operation, similar to polyuorene-based macromolecules.34–36
Received 26th September 2014 Accepted 17th November 2014 DOI: 10.1039/c4tc02173h /MaterialsC
Starburst 4,40,400-tris(carbazol-9-yl)triphenylamine-based deep-blue fluorescent emitters with tunable oligophenyl length for solution-processed undoped organic lightemitting diodes†
Introduction
Since 1987, organic light-emitting diodes (OLEDs) have attracted tremendous attention due to their potential applications in at-panel displays and solid-state lightings.1–10 To achieve fullcolor displays, three primary RGB luminescent materials with excellent stability, efficiency and color purity are required. With respect to green and red counterparts, it seems to be a big challenge to develop blue emitters, especially deep-blue ones that have a Commission Internationale de l'Eclairage (CIE) y coordinate value of <0.10, because the intrinsic wide bandgap would inevitably result in inefficient charge injection to an emitting layer (EML).11 Therefore, great efforts should be paid to the design of deep-blue emitters to push forward the commercialization of full-color OLEDs.
阿西莫夫
阿西莫夫引言罗比环舞推理捉兔说假话的家伙捉拿机器人逃避证据赤裸的太阳黎明世界的机器人机器人与银河帝国基地系列简介基地系列总目录基地与帝国楔子第二基地楔子百科全书学者心灵历史学家行商商业钜子市长哈里·谢顿基地危机空中石子奇妙的航程低能儿收容所格洛里亚的好朋友奇袭二百岁的寿星眼睛不仅用来看东西讲笑话的人天堂里的陌生人不朽的诗人法律之争终极答案人语石啊，巴顿，巴顿！第一定律讣告钢穴换个角度火星方式孩子最好的朋友镜象确定无疑的事奇妙的S奇特的人工脑如鱼得水死尘世界上的所有烦恼善良的秃鹫谁是凶手他们那时候多有趣响铃星光钥匙一只下金蛋的鹅最後的问题真爱终夜在火星宇宙站灶神星畔受困记丑孩子时代书城作品序号，作品名，初版出版社，初版年份1 Pebble In The Sky 苍穹微石，天空中的小石子，Doubleday 19502 I, Robot 我，机器人Gnome Press 19503 The Stars, Like Dust-- (Tyrann) 繁星若尘，宛若尘埃的星辰Doubleday 19514 Foundation 基地Gnome Press 19515 David Starr, Space Ranger 大卫·斯塔之太空巡逻兵Doubleday 19526 Foundation and Empire 基地与帝国Gnome Press 19527 The Currents of Space 星空暗流Doubleday 19528 Biochemistry and Human Metabolism 生物化学与人类的新陈代谢Williams & Wilkins 19529 Second Foundation 第二基地Gnome Press 195310 Lucky Starr and the Pirates of the Asteroids 幸运的斯塔与小行星上的海盗Doubleday 195311 The Caves of Steel 钢窟Doubleday 195412 Lucky Starr and the Oceans of Venus 幸运斯塔与金星海洋Doubleday 195413 The Chemicals of Life: Enzymes, Vitamins, and Hormones 生命化学：酶，维生素与激素Abelard-Schuman 195414 The Martian Way and Other Stories 马丁的路以及其他故事Doubleday 195515 The End of Eternity 永恒的终结Doubleday 195516 Races and People 人类种族Abelard-Schuman 195517 Lucky Starr and the Big Sun of Mercury 幸运斯塔与水星的大太阳Doubleday 195618 Chemistry and Human Health 化学与人类健康McGraw-Hill 195619 Inside The Atom 原子内部Abelard-Schuman 195620 The Naked Sun 裸阳Doubleday 195721 Lucky Starr and the Moons of Jupiter 幸运斯塔与木星的月亮Doubleday 195722 Building Blocks of the Universe 构筑宇宙的砖石Abelard-Schuman 195723 Earth Is Room Enough: Science FictionTales of Our Own Planet 地球有足够空间：我们自己星球的科幻故事Doubleday 195724 Only a Trillion 只不过是万亿Abelard-Schuman 195725 The World of Carbon 碳的世界Abelard-Schuman 195826 Lucky Starr and the Rings of Saturn 幸运斯塔与土星光环Doubleday 195827 The World of Nitrogen 氮的世界Abelard-Schuman 195828 The Death Dealers (A Whiff of Death) 死亡交易者（死亡的喘息）Avon 195829 Nine Tomorrows: Tales of the Near Future 九个明天：近未来故事集Doubleday 195930 The Clock We Live On 我们离不开的钟表Abelard-Schuman 195931 Words of Science, and the History Behind Them 科学名词以及它们背后的历史Houghton Mifflin 195932 Realm of Numbers 数字国度Houghton Mifflin 195933 The Living River 生机勃勃的河流Abelard-Schuman 196034 The Kingdom of the Sun 太阳的王国Abelard-Schuman 196035 Realm of Measure 测量探秘Houghton Mifflin 196036 Breakthroughs in Science 科学大突破Houghton Mifflin 196037 Satellites in Outer Space 外层空间的卫星Random House 196038 The Wellsprings of Life 生命的源泉Abelard-Schuman 196039 The Intelligent Man's Guide to Science 聪明人科学指南Basic Books 196040 The Double Planet 双行星Abelard-Schuman 196041 Words from the Myths 来源于神话的词语Houghton Mifflin 196142 Realm of Algebra 代数的国度Houghton Mifflin 196143 Life and Energy 生命与能量Doubleday 196244 Words in Genesis 《创世纪》中的词汇Houghton Mifflin 196245 Fact and Fancy 事实与想象Doubleday 196246 Words on the Map 地图上的词语Houghton Mifflin 196247 The Hugo Winners 雨果奖获奖者Doubleday 196248 The Search For The Elements 元素的探寻Basic Books 196249 Words from the Exodus 《出埃及记》中的词汇Houghton Mifflin 196350 The Genetic Code 遗传密码Orion Press 196351 The Human Body: Its Structure and Operation 人类的身体：它的结构与运行Houghton Mifflin 196352 Fifty Short Science Fiction Tales 短篇科幻小说五十篇Collier 196353 View from a Height 居高临下Doubleday 196354 The Kite That Won the Revolution 赢得革命的风筝Houghton Mifflin 196355 The Human Brain: Its Capacities and Functions 人类的大脑：容量与功能Houghton Mifflin 196456 A Short History of Biology 生物学简史Natural History Press 196457 Quick and Easy Math 简明数学Houghton Mifflin 196458 Adding a Dimension 增加一个维度Doubleday 196459 Planets For Man 人类行星Random House 196460 The Rest of the Robots 机器人的其他故事Doubleday 196461 Asimov's Biographical Encyclopedia of Science and Technology, 1st Ed. 阿西莫夫科学技术百科全书，第一版Doubleday 196462 A Short History of Chemistry 化学简史Doubleday 196563 The Greeks: A Great Adventure 希腊：伟大的冒险Houghton Mifflin 196564 Of Time and Space and Other Things 时间，空间，以及其他Doubleday 196565 The New Intelligent Man's Guide to Science 新聪明人科学指南Basic Books 196566 An Easy Introduction to the Slide Rule 计算尺速成介绍Houghton Mifflin 196567 Fantastic Voyage 奇妙的旅行Houghton Mifflin 196668 The Noble Gases 稀有气体Basic Books 196669 Inside The Atom (3rd revised edition) 原子内部（第三修订版）Abelard-Schuman 196670 The Neutrino: Ghost Particle of the Atom 中微子：原子中的幽灵Doubleday 196671 The Roman Republic 罗马共和国Houghton Mifflin 196672 Understanding Physics, Volume I 理解物理，第一卷Walker 196673 Understanding Physics, Volume II 理解物理，第二卷Walker 196674 Understanding Physics, Volume III 理解物理，第三卷Walker 196675 The Genetic Effects of Radiation 辐射对遗传的影响U.S. AEC 196676 Tomorrow's Children: Eighteen T ales of Fantasy and Science Fiction 明天的孩子：幻想故事与科幻故事十八篇Doubleday 196677 The Universe: From Flat Earth to Quasar 宇宙：从大地到类星体Walker 196678 From Earth to Heaven 从地球到天堂Doubleday 196679 The Moon 月球Follet 196780 Environments Out There 环境Scholastic/Abelard-Schuman 196781 The Roman Empire 罗马帝国Houghton Mifflin 196782 Through a Glass, Clearly 清晰地穿过玻璃New English Library 196783 Is Anyone There? 有人吗？Doubleday 196784 To the Ends of the Universe 到宇宙的尽头Walker 196785 Mars 火星Follet 196786 The Egyptians 埃及Houghton Mifflin 196787 Asimov's Mysteries 阿西莫夫神秘故事Doubleday 196888 Science, Numbers, and I 科学，数字，和我Doubleday 196889 Stars 星辰Follet 196890 Galaxies 银河Follet 196891 The Near East: 10,000 Years of History 东亚：10000年的历史Houghton Mifflin 196892 The Dark Ages 黑暗世代Houghton Mifflin 196893 Asimov's Guide To The Bible, Volume I 阿西莫夫圣经指南，第一卷Doubleday 196894 Words from History 历史中的词语Houghton Mifflin 196895 Photosynthesis 光合作用Basic Books 196996 The Shaping of England 英格兰的形成Houghton Mifflin 196997 Twentieth Century Discovery 二十世纪的发现Doubleday 196998 Nightfall and Other Stories 夜幕及其他故事Doubleday 196999 Asimov's Guide To The Bible, Volume II 阿西莫夫圣经指南，第二卷Doubleday 1969 100 Opus 100 作品100号Houghton Mifflin 1969101 ABC's of Space 空间小知识Walker 1969102 Great Ideas of Science 科学中的伟大思想Houghton Mifflin 1969103 The Solar System and Back 往返太阳系Doubleday 1970104 Asimov's Guide To Shakespeare, Volume I 阿西莫夫的莎士比亚指南，第一卷Doubleday 1970105 Asimov's Guide To Shakespeare, Volume II 阿西莫夫的莎士比亚指南，第二卷Doubleday 1970106 Constantinople: The Forgotten Empire 君士坦丁堡：被遗忘的帝国Houghton Mifflin 1970107 ABC's of the Ocean 海洋小知识Walker 1970108 Light 光Follet 1970109 The Stars in Their Courses 星星的一生Doubleday 1971110 Where Do We Go from Here? 我们何去何从？Doubleday 1971111 What Makes the Sun Shine? 什么让太阳发光？Little, Brown & Co. 1971112 The Sensuous Dirty Old Man 敏感的邋遢老人Walker 1971113 The Best New Thing 最好的新事物World Pub. Co. 1971114 Isaac Asimov's Treasury of Humor 艾萨克·阿西莫夫的幽默珍藏Houghton Mifflin 1971115 The Hugo Winners, Volume II 雨果奖获奖者，第二卷Doubleday 1971116 The Land of Canaan 迦南地Houghton Mifflin 1971117 ABC's of the Earth 地球小知识Walker 1971118 Asimov's Biographical Encyclopedia of Science and Technology, New Rev. Ed. 阿西莫夫的科学技术百科全书，新修版Doubleday 1972119 The Left Hand of the Electron 电子的左手Doubleday 1972120 Asimov's Guide to Science 阿西莫夫科学指南Basic Books 1972121 The Gods Themselves 神们自己Doubleday 1972122 More Words of Science 科学新词汇Houghton Mifflin 1972123 Electricity and Man 电与人U.S. AEC 1972124 ABC's of Ecology 生态学小知识Walker 1972125 The Early Asimov or, Eleven Years of Trying 阿西莫夫的早年生涯：努力拼搏的十一年Doubleday 1972126 The Shaping of France 法国的形成Houghton Mifflin 1972127 The Story of Ruth 路得记Doubleday 1972128 Ginn Science Program, Int. Level A 吉恩科学教程，初级，A级Ginn 1972129 Ginn Science Program, Int. Level C 吉恩科学教程，初级，C级Ginn 1972130 Asimov's Annotated "Don Juan" 阿西莫夫注释《唐璜》Doubleday 1972131 Worlds Within Worlds 世界中的世界U.S. AEC 1972132 Ginn Science Program, Int. Level B 吉恩科学教程，初级，B级Ginn 1972133 How Did We Find Out the Earth Is Round? 我们是如何发现地球是圆的？Walker 1973134 Comets and Meteors 彗星与流星Follet 1973135 The Sun 太阳Follet 1973136 How Did We Find Out About Electricity? 我们是如何发现电子的？Walker 1973137 The Shaping of North America: From Earliest Times to 1763 北美洲的形成：从最初到1763年Houghton Mifflin 1973138 Today and Tomorrow and... 今天，明天，和…… Doubleday 1973139 Jupiter, the Largest Planet 木星，最大的行星Lothrop, Lee, & Shepard 1973140 Ginn Science Program, Adv. Level A 吉恩科学教程，高级，A级Ginn 1973141 Ginn Science Program, Adv. Level B 吉恩科学教程，高级，B级Ginn 1973142 How Did We Find Out About Numbers? 我们是如何发现数字的？Walker 1973143 Please Explain 请解释Houghton Mifflin 1973144 The Tragedy of the Moon 月球的悲剧Abelard-Schuman 1973145 How Did We Find Out About Dinosaurs? 我们是如何发现恐龙的？Walker 1973 146 The Best of Isaac Asimov 阿西莫夫最佳作品集Sphere 1973147 Nebula Award Stories Eight 星云奖作品，八Harper & Row 1973148 Asimov on Astronomy 阿西莫夫讲天文Doubleday 1974149 The Birth of the United States 美国的诞生Houghton Mifflin 1974150 Have You Seen These? 你是如何看到这些的？NESRAA 1974151 Before The Golden Age: A Science Fiction Anthology of the 1930s 黄金时代之前：1930年代科幻小说选集Doubleday 1974152 Our World in Space 宇宙空间中我们的世界New York Graphic Society 1974153 How Did We Find Out About Germs? 我们是如何发现细胞的？Walker 1974154 Asimov's Annotated "Paradise Lost" 阿西莫夫注释《失乐园》Doubleday 1974155 Tales of the Black Widowers 黑鳏夫故事集Doubleday 1974156 Earth: Our Crowded Spaceship 地球：拥挤的宇宙飞船John Day 1974157 Asimov on Chemistry 阿西莫夫讲化学Doubleday 1974158 How Did We Find Out About Vitamins? 我们是如何发现维生素的？Walker 1974 159 Of Matters Great and Small 巨大和微小的事物Doubleday 1975160 The Solar System 太阳系Follet 1975161 Our Federal Union 我们的联邦Houghton Mifflin 1975162 How Did We Find Out About Comets? 我们是如何发现彗星的？Walker 1975163 Science Past, Science Future 科学的过去，科学的未来Doubleday 1975164 Buy Jupiter and Other Stories 购买木星，以及其他故事Doubleday 1975165 Eyes on the Universe: A History of the Telescope 观察宇宙的眼睛：望远镜的历史Houghton Mifflin 1975166 Lecherous Limericks 放荡的打油诗Walker 1975167 The Heavenly Host 幽灵天体Walker 1975168 The Ends of the Earth: The Polar Regions of the World 地球的尽头：极地Weybright & Talley 1975169 How Did We Find Out About Energy? 我们是如何发现能量的？Walker 1975170 "The Dream", "Benjamin's Dream", and "Benjamin's Bicentennial Blast" 梦，本杰明的梦，以及本杰明的200年大爆炸Benjamin Franklin Keeps. 1976171 Asimov on Physics 阿西莫夫讲物理Doubleday 1976172 Murder at The ABA (Authorised Murder [U.K.]) ABA谋杀案（授权的谋杀案[英]）Doubleday 1976173 How Did We Find Out About Atoms? 我们是如何发现原子的？Walker 1976174 Good Taste 好味道Apocalypse Press 1976175 The Planet That Wasn't 不是行星的行星Doubleday 1976176 The Bicentennial Man and Other Stories 活了200年的人，以及其他故事Doubleday 1976177 More Lecherous Limericks 更放荡的打油诗Walker 1976178 More Tales of the Black Widowers 更多的黑鳏夫故事Doubleday/Crime Club 1976 179 Alpha Centauri, the Nearest Star 半人马座阿尔法星，最近的恒星Lothrop, Lee, & Shepard 1976180 How Did We Find Out About Nuclear Power? 我们是如何发现核能的？Walker 1976 181 Familiar Poems Annotated 诗歌注释Doubleday 1977182 The Collapsing Universe: The Story of Black Holes 宇宙坍塌：黑洞的故事Walker 1977183 Asimov on Numbers 阿西莫夫讲数字Doubleday 1977184 How Did We Find Out About Outer Space? 我们是如何发现外层空间的？Walker 1977185 Still More Lecherous Limericks 愈加放荡的打油诗Walker 1977186 The Hugo Winners, Volume III 雨果奖获奖者，第三卷Doubleday 1977187 The Beginning and the End 开始与终结Doubleday 1977188 Mars, the Red Planet 火星，红色行星Lothrop, Lee, & Shepard 1977189 The Golden Door 金门Houghton Mifflin 1977190 The Key Word and Other Mysteries 关键词以及其他神秘故事Walker 1977191 Asimov's Sherlockian Limericks 阿西莫夫的福尔摩斯打油诗Mysterious 1977192 One Hundred Great Science Fiction Short-Short Stories 百篇优秀微型科幻小说Doubleday 1978193 Quasar, Quasar, Burning Bright 类星体，类星体，闪闪发亮Doubleday 1978194 How Did We Find Out About Earthquakes? 我们是如何发现地震的？Walker 1978 195 Animals of the Bible 圣经里的动物Doubleday 1978196 Limericks: Too Gross; or Two Dozen Dirty Stanzas 打油诗：太低俗；又称两篓俗诗W. W. Norton 1978197 How Did We Find Out About Black Holes? 我们是如何发现黑洞的？Walker 1978 198 Life and Time 生命与时间Doubleday 1978199 Saturn and Beyond 土星及其他Lothrop, Lee, & Shepard 1979200 Opus 200 作品200号Houghton Mifflin 1979201 In Memory Yet Green 记忆犹新Doubleday 1979202 Isaac Asimov Presents the Great SF Stories, 1: 1939 艾萨克·阿西莫夫推荐优秀科幻小说，第一卷：1939 DAW Books 1979203 Extraterrestrial Civilizations 外星文明Crown 1979204 How Did We Find Out About Our Human Roots? 我们是如何发现我们的祖先？Walker 1979205 Isaac Asimov Presents the Great SFStories, 2: 1940 艾萨克·阿西莫夫推荐优秀科幻小说，第二卷：1940 DAW Books 1979206 The Road to Infinity 通向无限之路Doubleday 1979207 A Choice of Catastrophes 终极抉择Simon & Schuster 1979208 The Science Fictional Solar System 科幻小说中的太阳系Harper & Row 1979209 The Thirteen Crimes of Science Fiction 科幻小说的十三宗案件Doubleday 1979 210 Isaac Asimov's Book of Facts 艾萨克·阿西莫夫的现实著作Grosset & Dunlap 1979 211 How Did We Find Out About Antarctica? 我们是如何发现南极的？Walker 1979212 Casebook of the Black Widowers 黑鳏夫探案集Doubleday 1980213 The Future in Question 充满疑问的未来Fawcett Crest 1980214 Isaac Asimov Presents the Great SF Stories, 3: 1941 艾萨克·阿西莫夫推荐优秀科幻小说，第三卷：1941 DAW Books 1980215 How Did We Find Out About Oil? 我们是如何发现石油的？Walker 1980216 In Joy Still Felt 欢乐依旧Doubleday 1980217 Who Done It? 谁干的？Houghton Mifflin 1980218 Space Mail 太空邮件Fawcett Crest 1980219 Microcosmic T ales: 100 Wondrous Science Fiction Short-Short Stories 微型宇宙故事：100篇绝妙微型科幻小说Taplinger 1980220 Isaac Asimov Presents the Great SF Stories, 4: 1942 艾萨克·阿西莫夫推荐优秀科幻小说，第四卷：1942 DAW Books 1980221 The Seven Deadly Sins of Science Fiction 科幻小说七宗罪Fawcett Crest 1980 222 The Annotated "Gulliver's Travels" 注释《格列佛游记》Clarkson N. Potter 1980 223 How Did We Find Out About Coal? 我们是如何发现煤的？Walker 1980224 The Future I 未来，第一卷Fawcett Crest 1981225 In the Beginning 最初Crown/Stonesong Press 1981226 Isaac Asimov Presents the Great SF Stories, 5: 1943 艾萨克·阿西莫夫推荐优秀科幻小说，第五卷：1943 DAW Books 1981227 Asimov on Science Fiction 阿西莫夫讲科幻Doubleday 1981228 Venus, Near Neighbor of the Sun 金星，太阳的近邻Lothrop, Lee, & Shepard 1981 229 Three by Asimov 阿西莫夫作品三篇Targ 1981230 How Did We Find Out About Solar Power? 我们是如何发现太阳能的？Walker 1981 231 How Did We Find Out About Volcanoes? 我们是如何发现真空的？Walker 1981 232 Visions of the Universe 宇宙景观The Cosmos Store 1981233 Catastrophes! 大灾难Fawcett Crest 1981234 Isaac Asimov Presents the Best Science Fiction of the 19th Century 艾萨克·阿西莫夫推荐19世纪最佳科幻小说Beaufort Books 1981235 The Seven Cardinal Virtues of Science Fiction 科幻小说的七大妙处Fawcett Crest 1981236 Fantastic Creatures: An Anthology of Fantasy and Science Fiction 梦幻创造者：幻想与科幻百科全书Franklin Watts 1981237 The Sun Shines Bright 光芒万丈的太阳Doubleday 1981238 Change!: Seventy-one Glimpses of theFuture 剧变：未来的七十一个预测Houghton Mifflin 1981239 Raintree Reading Series I 雨林系列读物，第一辑Raintree 1981Travels Through Time 时间旅行Thinking Machines 会思考的机器Wild Inventions 疯狂的发明After The End 末日之后240 A Grossery of Limericks 打油诗的俗气W. W. Norton 1981241 Miniature Mysteries: One Hundred Malicious Little Mystery Stories 微型神秘故事：邪恶神秘故事一百篇Taplinger 1981242 The Twelve Crimes of Christmas 化学的十二宗罪Avon 1981243 Isaac Asimov Presents the Great SF Stories, 6: 1944 艾萨克·阿西莫夫推荐优秀科幻小说，第六卷：1944 DAW Books 1981244 Space Mail II 太空邮件，2 Fawcett Crest 1982245 Tantalizing Locked Room Mysteries 引人入胜的密室神秘故事Walker 1982246 TV: 2000 电视：2000 Fawcett Crest 1982247 Laughing Space 开心的太空Houghton Mifflin 1982248 How Did We Find Out About Life In the Deep Sea 我们是如何发现深海生物的？Walker 1982249 The Complete Robot 最终的机器人Doubleday 1982250 Speculations 推测Houghton Mifflin 1982251 Flying Saucers 飞碟Fawcett Crest 1982252 Exploring the Earth and the Cosmos 探索地球和宇宙Crown 1982253 Raintree Reading Series II 雨林系列读物，第二辑Raintree 1982 Earth Invaded 被侵蚀的地球Mad Scientists 疯狂的科学家Mutants 突变Tomorrow's TV 明日的电视254 How Did We Find Out About the Beginning of Life? 我们是如何发现生命的开端？Walker 1982255 Dragon Tales 龙的故事Fawcett Crest 1982256 The Big Apple Mysteries 大苹果神秘故事集Avon 1982257 Asimov's Biographical Encyclopedia of Science and T echnology, 2nd Rev. Ed. 阿西莫夫科学技术百科全书，第二版Doubleday 1982258 Isaac Asimov Presents the Great SF Stories, 7: 1945 艾萨克·阿西莫夫推荐优秀科幻小说，第七卷：1945 DAW Books 1982259 Isaac Asimov Presents Superquiz 艾萨克·阿西莫夫推荐超级智力游戏Dembner Books 1982260 The Last Man on Earth 地球上的最后一个人Fawcett Crest 1982261 Science Fiction A to Z: A Dictionary of Great Science Fiction Themes 科幻小说A到Z：科幻小说主题的辞典Houghton Mifflin 1982262 Foundation's Edge 基地边缘Doubleday 1982263 Isaac Asimov Presents the Best Fantasy of the 19th Century 艾萨克·阿西莫夫推荐19世纪最佳幻想故事Beaufort Books 1982264 Isaac Asimov Presents the Great SF Stories, 8: 1946 艾萨克·阿西莫夫推荐优秀科幻小说，第八卷：1946 DAW Books 1982265 How Did We Find Out About the Universe? 我们是如何发现宇宙的？Walker 1982 266 Counting the Eons 对年代的计数Doubleday 1983267 The Winds of Change and Other Stories 剧变之风以及其他故事Doubleday 1983 268 Isaac Asimov Presents the Great SF Stories, 9: 1947 艾萨克·阿西莫夫推荐优秀科幻小说，第九卷：1947 DAW Books 1983269 Show Business Is Murder 演艺业是谋杀Avon 1983270 Hallucination Orbit: Psychology In Science Fiction 幻想的轨道：科幻小说中的心理学Farrar, Straus, & Giroux 1983271 Caught In the Organ Draft: Biology In Science Fiction 迷人的图像：科幻小说中的生物学Farrar, Straus, & Giroux 1983272 The Roving Mind 意识的图景Prometheus Books 1983273 The Science Fiction Weight-Loss Book 轻装本科幻小说Crown 1983274 The Measure of the Universe 测量宇宙Harper & Row 1983275 Isaac Asimov Presents the Best Horror and Supernatural Stories of the 19th Century 艾萨克·阿西莫夫推荐19世纪最佳恐怖和超自然故事Beaufort Books 1983276 Starships: Stories Beyond the Boundaries of the Universe 星船：飞越宇宙边际故事集Fawcett Crest 1983277 The Union Club Mysteries 联合俱乐部神秘故事Doubleday 1983278 Norby, the Mixed-up Robot 诺比，糊涂的机器人Walker 1983279 Isaac Asimov Presents the Great SF Stories, 10: 1948 艾萨克·阿西莫夫推荐优秀科幻小说，第十卷：1948 DAW Books 1983280 How Did We Find Out About Genes? 我们是如何发现基因的？Walker 1983281 The Robots of Dawn 曙光中的机器人Doubleday 1983282 Thirteen Horrors of Halloween 万圣节的十三个恐怖故事Avon 1983283 Creations: The Quest For Origins in Story and Science 创造：探寻故事与科学中的原型Crown 1983284 Isaac Asimov Presents Superquiz II 艾萨克·阿西莫夫推荐超级智力游戏，第二卷Dembner Books 1983285 Wizards 巫师NAL 1983286 Those Amazing Electronic Thinking Machines!: An Anthology of Robot and Computer Stories 奇妙的思考机器：机器人与计算机故事百科全书Franklin Watts 1983287 Computer Crimes and Capers 计算机犯罪与把戏Academy Chicago Pub. 1983 288 Intergalactic Empires 星际帝国NAL 1983289 Machines That Think: The Best Science Stories About Robots and Computers 会思考的机器：机器人与计算机最佳科幻小说集Holt, Rinehart, & Winston 1983290 X Stands for Unknown X代表未知Doubleday 1984291 One Hundred Great Fantasy Short-Short Stories 百篇优秀微型幻想小说Doubleday 1984292 Raintree Reading Series 3 雨林系列读物，第三辑Raintree 1984 Bug Awful 害虫Children Of The Future 未来的孩子The Immortals 不朽Time Warps 时间弯曲293 Isaac Asimov Presents the Great SF Stories, 11: 1949 艾萨克·阿西莫夫推荐优秀科幻小说，第11卷：1949 DAW Books 1984294 Witches 巫婆NAL 1984295 Murder on the Menu 菜单谋杀案Avon 1984296 Young Mutants 新突变体Harper & Row 1984297 Isaac Asimov Presents the Best Science Fiction Firsts 艾萨克·阿西莫夫推荐最优秀科幻小说Beaufort Books 1984298 Norby's Other Secret 诺比的另一个秘密Walker 1984299 How Did We Find Out About Computers? 我们是如何发现计算机的？Walker 1984 300 Opus 300 作品300号Houghton Mifflin 1984301 The Science Fictional Olympics 科幻小说奥林匹克NAL 1984302 Fantastic Reading: Stories & Activities for Grade 5-8 美妙的阅读：适合5-8年级的故事和活动Scott Foresman & Co. 1984303 Banquets of the Black Widowers 黑鳏夫们的宴会Doubleday 1984304 Election Day 2084: Science Fiction Stories on the Politics of the Future 2084年选举日：未来政治科幻小说Prometheus Books 1984305 Isaac Asimov's Limericks for Children 艾萨克·阿西莫夫献给孩子们的打油诗故事Caedmon 1984306 Isaac Asimov Presents the Great SF Stories, 12: 1950 艾萨克·阿西莫夫推荐优秀科幻小说，第12卷：1950 DAW Books 1984307 Young Extraterrestrials 新出现的外星人Harper & Row 1984308 Sherlock Holmes Through Time and Space 穿越时空的福尔摩斯Bluejay Books 1984309 Asimov's New Guide to Science 阿西莫夫的新科学指南Basic Books 1984310 Supermen 超人NAL 1984311 Baker's Dozen: 13 Short Fantasy Novels 面包师的一打：短篇幻想故事13篇Crown 1984312 How Did We Find Out About Robots? 我们是如何发现机器人的？Walker 1984313 Asimov's Guide to Halley's Comet 阿西莫夫的哈雷彗星指南Walker 1985314 Cosmic Knights 宇宙骑士NAL 1985315 The Hugo Winners, Volume IV 雨果奖获奖者，第四卷Doubleday 1985316 Young Monsters 新出现的怪物Harper & Row 1985317 The Exploding Suns: The Secrets of theSupernovas 爆发的太阳：超新星的秘密E. P. Dutton 1985318 Norby and the Lost Princess 诺比和失踪的公主Walker 1985319 Spells 拼写NAL 1985320 How Did We Find Out About the Atmosphere? 我们是如何发现大气的？Walker 1985321 Living in the Future 未来的生活Harmony House 1985322 Robots, Machines In Man's Image 机器人，人类设计的机器Harmony House 1985 323 The Edge of Tomorrow 明天的边际Tor/Tom Doherty Associates 1985324 Great Science Fiction Stories by the World's Great Scientists 世界著名科学家创作的科幻小说集Donald I. Fine 1985325 Isaac Asimov Presents the Great SF Stories, 13: 1951 艾萨克·阿西莫夫推荐优秀科幻小说，第13卷：1951 DAW Books 1985326 The Subatomic Monster 原子内的怪物Doubleday 1985327 The Disappearing Man and Other Mysteries 消失的男人以及其他神秘故事Walker 1985328 Robots and Empire 机器人与帝国Doubleday 1985329 Amazing Stories: Sixty Years of the Best Science Fiction 惊奇故事：出现最佳科幻小说的六十年TSR Inc. 1985330 Young Ghosts 新出现的幽灵Harper & Row 1985331 Baker's Dozen: Thirteen Short Science Fiction Novels 面包师的一打：短篇科幻小说13篇Crown 1985332 It's Such a Beautiful Day 多么美丽的一天Creative Education 1985333 Norby and the Invaders 诺比和入侵者Walker 1985334 Giants 巨人NAL 1985335 How Did We Find Out About DNA? 我们是如何发现DNA的？Walker 1985336 The Alternate Asimovs 多面手阿西莫夫Doubleday 1986337 Isaac Asimov Presents the Great SF Stories, 14: 1952 艾萨克·阿西莫夫推荐优秀科幻小说，第14卷：1952 DAW Books 1986338 Comets 彗星NAL 1986339 Young Star Travelers 新出现的星际旅行者Harper & Row 1986340 The Hugo Winners, Volume V 雨果奖获奖者，第五卷Doubleday 1986341 The Dangers of Intelligence and Other Science Essays 智能的危险以及其他科学随笔Houghton Mifflin 1986342 Mythical Beasties 想象出来的怪兽NAL 1986343 How Did We Find Out About the Speed of Light? 我们是如何发现光速的？Walker 1986344 Futuredays: A Nineteenth-Century Vision of the Year 2000 未来的日子：19世纪想象的2000年Henry Holt 1986345 Science Fiction by Asimov 阿西莫夫科幻小说Davis Publications 1986346 Tin Stars 罐装星星NAL 1986347 The Best Science Fiction of Isaac Asimov 艾萨克·阿西莫夫最佳科幻小说Doubleday 1986348 The Best Mysteries of Isaac Asimov 艾萨克·阿西莫夫最佳神秘小说Doubleday 1986 349 Foundation and Earth 基地与地球Doubleday 1986350 Robot Dreams 机器人的梦Byron Preiss 1986351 Norby and the Queen's Necklace 诺比和女王的项链Walker 1986352 Magical Wishes 充满魔力的希望NAL 1986353 Isaac Asimov Presents the Great SF Stories, 15: 1953 艾萨克·阿西莫夫推荐优秀科幻小说，第15卷：1953 DAW Books 1986354 Far as Human Eye Could See 目光的尽头Doubleday 1987355 The Twelve Frights of Christmas 化学的十二个恐怖事件Avon 1986356 How Did We Find Out About Blood? 我们是如何发现血液的？Walker 1987357 Past, Present, and Future 过去，现在和未来Prometheus Books 1987358 Isaac Asimov Presents Superquiz III 艾萨克·阿西莫夫推荐超级智力游戏，第三卷Dembner Books 1987359 How Did We Find Out About Sunshine? 我们是如何发现阳光的？Walker 1987360 Isaac Asimov Presents the Great SF Stories, 16: 1954 艾萨克·阿西莫夫推荐优秀科幻小说，第16卷：1954 DAW Books 1987361 Young Witches and Warlocks 新出现的女巫和术士Harper & Row 1987362 How to Enjoy Writing: A Book of Aid and Comfort 如何享受于写作Walker 1987363 Devils 魔鬼NAL 1987364 Norby Finds a Villain 诺比找到一个恶棍Walker 1987365 Fantastic Voyage II: Destination Brain 奇妙的旅程二：目的地，大脑Doubleday 1987 366 Hound Dunnit 猎犬杜内特Carroll & Graf 1987367 Space Shuttles 航天飞机NAL 1987368 How Did We Find Out About the Brain? 我们是如何发现大脑的？Walker 1987369 Did Comets Kill the Dinosaurs? 彗星灭绝了恐龙吗？Gareth Stevens, Inc 1987370 Beginnings: The Story of Origins -of Mankind, Life, the Earth, the Universe 开端：人类，生命，地球，宇宙起源的故事Walker 1987371 Atlantis 亚特兰蒂斯NAL 1988372 Isaac Asimov Presents the Great SF Stories, 17: 1955 艾萨克·阿西莫夫推荐优秀科幻小说，第17卷：1955 DAW Books 1988373 Asimov's Annotated Gilbert and Sullivan 阿西莫夫注释《吉尔伯特和沙利文》Doubleday 1988374 Isaac Asimov Presents From Harding to Hiroshima 艾萨克·阿西莫夫敬献从哈丁到广岛Dembner Books 1988375 How Did We Find Out About Superconductivity? 我们是如何发现超导体的？Walker 1988376 Other Worlds of Isaac Asimov 艾萨克·阿西莫夫的其他世界Avenel 1987377 Isaac Asimov's Book of Science and Nature Quotations 艾萨克·阿西莫夫的科学与自然著作语录Blue Cliff 1988378 The Relativity of Wrong 错误的相对性Doubleday 1988379 Prelude to Foundation 基地前奏Doubleday 1988380 Encounters 接触Headline 1988381 The Asteroids 小行星Gareth Stevens, Inc 1988382 The Earth's Moon 地球的月亮Gareth Stevens, Inc 1988383 Mars: Our Mysterious Neighbor 火星：我们的神秘邻居Gareth Stevens, Inc 1988 384 Our Milky Way and Other Galaxies 我们那乳液般的银河以及其他银河系Gareth Stevens, Inc 1988385 Quasars, Pulsars, and Black Holes 类星体，脉冲星，以及黑洞Gareth Stevens, Inc 1988386 Rockets, Probes, and Satellites 火箭，探测器，以及卫星Gareth Stevens, Inc 1988 387 Our Solar System 我们的太阳系Gareth Stevens, Inc 1988388 The Sun 太阳Gareth Stevens, Inc 1988389 Uranus: The Sideways Planet 天王星：偏远的行星Gareth Stevens, Inc 1988390 History of Biology (a chart)* 生物学的历史（图表）Carolina Biological Suppls. 1988 391 Isaac Asimov Presents the Best Crime Stories of the 19th Century 艾萨克·阿西莫夫推荐19世纪最佳犯罪小说Dembner Books 1988392 The Mammoth Book of Classic Science Fiction: Short Novels of the 1930's 经典科幻小说大全：1930年代的短篇小说Carroll & Graf 1988393 Monsters 怪物NAL 1988394 Isaac Asimov Presents the Great SF Stories, 18: 1956 艾萨克·阿西莫夫推荐优秀科幻小说，第18卷：1956 DAW Books 1988395 Azazel 阿撒泻勒Doubleday 1988396 Isaac Asimov's Science Fiction and Fantasy Story-a-Month 1989 Calendar* 艾萨克·阿西莫夫科幻小说与幻想小说挂历，1989年Pomegranate Calendars & Bks 1988 397 Ghosts 幽灵NAL 1988398 Saturn: The Ringed Beauty 土星：围绕着光环的美人Gareth Stevens, Inc 1988 399 How Was the Universe Born? 宇宙是如何诞生的？Gareth Stevens, Inc 1988400 Earth: Our Home Base 地球：我们的大本营Gareth Stevens, Inc 1988401 Ancient Astronomy 古代的天文学Gareth Stevens, Inc 1988402 Unidentified Flying Objects 不明飞行物Gareth Stevens, Inc 1988403 Space Spotter's Guide 宇宙探测器指南Gareth Stevens, Inc 1988404 Norby Down to Earth 诺比光临地球Walker 1988405 The Sport of Crime 犯罪行为Lynx 1988406 How Did We Find Out About Microwaves? 我们是如何发现微波的？Walker 1989 407 Isaac Asimov Presents the Great SF Stories, 19: 1957 艾萨克·阿西莫夫推荐优秀科幻小说，第19卷：1957 DAW Books 1989408 Asimov's Galaxy: Reflections on Science Fiction 阿西莫夫的银河系：科幻小说的映像Doubleday 1989409 All the Troubles of the World 世界的所有麻烦事Creative Education 1989410 Franchise 特权Creative Education 1989411 Robbie 罗比Creative Education 1989412 Sally 萨莉Creative Education 1989413 Isaac Asimov Presents Tales of the Occult* 艾萨克·阿西莫夫推荐玄秘故事集Prometheus Books 1989414 Purr-fect Crime 稍完美犯罪Lynx 1989415 Is There Life On Other Planets? 其他行星上有生命吗？Gareth Stevens, Inc 1989416 Science Fiction, Science Fact 科学幻想，科学事实Gareth Stevens, Inc 1989417 Mercury: The Quick Planet 水星：飞毛腿行星Gareth Stevens, Inc 1989418 Space Garbage 太空垃圾Gareth Stevens, Inc 1989419 Jupiter: The Spotted Giant 木星：长斑点的巨人Gareth Stevens, Inc 1989420 The Birth and Death of Stars 星星的诞生与死亡Gareth Stevens, Inc 1989421 The Asimov Chronicles: Fifty Years of Isaac Asimov 阿西莫夫编年史：艾萨克·阿西莫夫的五十年Dark Harvest 1989422 Robots 机器人NAL 1989423 History of Mathematics (a chart) 数学的历史（图表）Carolina Biological Suppls. 1989424 Think About Space: Where Have We Been and Where Are We Going? 对太空的思考：我们身处何方？我们去向何处？Walker 1989425 Isaac Asimov Presents Superquiz IV 艾萨克·阿西莫夫推荐超级智力游戏，第四卷Dembner Books 1989426 The Tyrannosaurus Prescription: and One Hundred Other Science Essays 霸王龙处方：另一百篇科学随笔Prometheus Books 1989427 Asimov On Science: A 30 Year Retrospective 1959-1989 阿西莫夫讲科学：三十年回顾1959-1989 Doubleday 1989428 Visions of Fantasy: Tales From the Masters 幻想的影像：大师作品集Doubleday 1989429 Nemesis 报应Doubleday 1989430 Curses 诅咒NAL 1989431 Asimov's Chronology of Science and Discovery 阿西莫夫的科学与发现编年史Harper & Row 1989432 How Did We Find Out About Photosynthesis? 我们是如何发现光合作用的？Walker 1989433 The Complete Science Fair Handbook 科学博览会完全手册Scott Foresman & Co 1989434 Little Treasury of Dinosaurs (5 book set) 恐龙小百科（五本套装）Outlet 1989 Giant Dinosaurs (vol. 1) 巨大的恐龙Armored Dinosaurs (vol. 2) 顶盔贯甲的恐龙Small Dinosaurs (vol. 3) 小个子恐龙Sea Reptiles and Flying Reptiles(vol. 4) 大洋中的爬虫和飞行的爬虫Meat-Eating Dinosaurs and Horned 食肉恐龙和长犄角的恐龙Dinosaurs (vol. 5) 恐龙435 The New Hugo Winners 新雨果奖获奖者Wynwood Press 1989436 Senior Sleuths: A Large Print Anthology of Mysteries and Puzzlers 高等侦探：神秘故事与悬疑故事大选集G. K. Hall & Co. 1989437 Norby and Yobo's Great Adventure 诺比和约布的伟大冒险Walker 1989438 Mythology and the Universe 神话学与宇宙Gareth Stevens, Inc 1989439 Colonizing the Planets and the Stars 星际殖民Gareth Stevens, Inc 1989440 Astronomy Today 今日的天文学Gareth Stevens, Inc 1989441 Pluto: A Double Planet? 冥王星：双行星？Gareth Stevens, Inc 1989442 Piloted Space Flights 宇宙飞行的导航Gareth Stevens, Inc 1989。
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ExtragalacticStarClusters
IAUSymposiumSeries,Vol.Vol.207,2001
EvaK.Grebel,DougGeisler,andDanteMinniti,eds.
Tidally-inducedSuperStarClustersinM82
R.deGrijs
InstituteofAstronomy,Univ.ofCambridge,MadingleyRoad,
CambridgeCB30HA,UK
R.W.O’Connell
AstronomyDept.,Univ.ofVirginia,P.O.Box3818,Charlottesville,
VA22903,USA
J.S.Gallagher,iii
AstronomyDept.,Univ.ofWisconsin,475N.CharterStr.,Madison,
WI53706,USA
Abstract.UsingnewHSTimaging,weidentifyalarge,evolvedsystem
ofsuperstarclustersinadiskregionjustoutsidethestarburstcorein
theprototypicalstarburstgalaxyM82,“M82B.”Thisregionhasbeen
suspectedtobeafossilstarburstsiteinwhichanintenseepisodeofstar
formationoccurredover100Myrago,whichisnowconfirmedbyour
derivedagedistribution.Itsuggestssteady,continuingclusterformation
atamodestrateatearlytimes(>2Gyrago),followedbyaconcentrated
formationepisode∼600Myragoandmorerecentsuppressionofclus-
terformation.Thepeakepisodecoincideswithindependentdynamical
estimatesforthelasttidalencounterwithM81.
1.M82,theprototypicalstarburstgalaxy
ObservationsfromradiotoX-raysshowevidenceforatidally-inducedstarburst
inthecenterofM82(e.g.,Telesco1988)Infact,thereisnowevidencethat
M82hasundergonemultipleepisodesofintensestarformation(cf.Marcum
&O’Connell1996,deGrijs,O’Connell&Gallagher2001).“M82B,”thefossil
starburstregion,hasexactlythepropertiesofanevolvedstarburstwithasimilar
amplitudetotheactiveburst(Marcum&O’Connell1996).Thus,M82isa
uniquestarburstgalaxy,sincenoothergalaxyofferstheopportunitytostudy
twodiscretestarburstsatsuchcloserange!ByanalogywiththeHSTresults
fromtheactivestarburstregion(O’Connelletal.1994,1995),weexpected
M82Btohavecontainedacomplementofluminoussuperstarclusters.Itis
possiblethatmostofthestarformationinstarburststakesplaceintheformof
suchconcentratedclusters;inM82,wedonotobserveanyoutsidethestarburst
regions.
Thecombinationofobservationsofboththeactiveandthefossilstarburst
sitesinM82providesauniquephysicalenvironmentforthestudyofthestellar
anddynamicalevolutionofstarclustersystems
1
2R.deGrijsetal.
Figure1.AgedistributionofthestarclustersinM82B.Shadedhis-
togram:well-determinedages;openhistogram:upperorlowerlimits
only(cf.deGrijsetal.2001).
2.ThestarformationhistoryinM82
BasedonHST/WFPC2observationsoftwoadjacentfieldsinM82B(inF439W,
F555WandF814W),wedetected∼100(slightly)evolvedstarclusters.The
clustersbrighterthanV=22.5exhibitawiderangeofages,from∼30Myrto
over10Gyr.Thereisastrongpeakofclusterformationat∼600Myr,ineither
representationinFig.1;veryfewclustersareyoungerthan300Myr.
Ourresultssuggeststeady,continuingclusterformationataverymodest
rateatearlytimes(>2Gyrago),followedbyaconcentratedformationepisode
lastingfrom400–1000Myragoandasubsequentsuppressionofclusterforma-
tion.Thus,itappearsthatthelasttidalencounterbetweenM82andM81∼
500–800Myragohadamajorimpactonwhatwasprobablyanotherwisenor-
mal,quiescent,diskgalaxy.Itcausedaconcentratedburstofstarformation
activity,whichdecreasedrapidlywithinafewhundredMyr.
M82Bhasevidentlynotbeenaffectedbythemorerecent(<30Myr)
starburstepisodenowcontinuinginthecentralregions.
References
deGrijsR.,O’ConnellR.W.,GallagherJ.S.,2001,AJ,121,768
MarcumP.,O’ConnellR.W.1996,in:FromStarstoGalaxies:TheImpact
ofStellarPhysicsonGalaxyEvolution,eds.LeithererC.,Fritze-von
AlvenslebenU.,HuchraJ.,SanFrancisco:ASP,p.419
O’ConnellR.W.,GallagherJ.S.,HunterD.A.1994,ApJ,433,65
O’ConnellR.W.,GallagherJ.S.,HunterD.A.,ColleyW.N.1995,ApJ,446,L1
TelescoC.M.1988,ARA&A26,343