托福天文词汇astronomy（推荐）由刀豆文库小编整理，希望给你工作、学习、生活带来方便，猜你可能喜欢“托福天文词汇”。
天文词汇
Asteroids 小行星
Minor bodies of the solar system, formed by rock, metal, or a mixture of both.Most asteroids orbit the Sun between the orbits of Mars and Jupiter.Their size ranges from dozens of feet to hundreds of miles.Atmosphere 大气层
Layer of gas retained around a planet by its gravity.It is also the outer layer of matter in a star, where the energy produced in the star's interior is emitted in the form of radiation.Atom 原子
The smallest part of an element that partakes of all the element's properties.It is generally composed of three subatomic particles: the neutron, the proton, and the electron.Aurora 极光；曙光
Luminous phenomenon, with red and green layers, visible in the skies of the polar regions.The auroras are caused by the collision of solar particles with the Earth's atmosphere.Big Bang 大爆炸
Cosmological theory aerting that the universe began to exist as a result of a great explosion that occurred some 14 billion years ago.Big Crunch 大压缩
Cosmological theory aerting that the universe would undergo a final, complete collapse if it were to begin to contract.Black Hole 黑洞
Celestial body so dense that not even light can escape its gravity.Comet 彗星
Object made of ice and rock dust.When a comet approaches the Sun, the growing heat causes the ice to evaporate, forming a gaseous head and a tail of dust and gas pointing away from the Sun.Constellation 星系，星座
Group of stars in the sky.Constellations tend to bear the names of mythological characters or creatures.To astronomers, the constellations demarcate regions of the sky.Core 地心
In a planet, a solid, high-preure central ma;in a star, the central region undergoing nuclear fusion;in a galaxy, the innermost light-years.Crater 弹坑
Circular depreion formed by the impact of a meteorite on the surface of a natural satellite or a planet.Crust 地壳
Rocky layer of the surface of a planet or natural satellite.Decay 衰变
Proce by which radioactive elements and unstable particles become stable substances.Also the way in which black holes eventually disappear.Density 密度
Degree of solidity of a body(its ma divided by its volume).Eclipse 日蚀，月食
Visual concealment of one celestial body by another.A lunar eclipse occurs when the Moon paes into the Earth's shadow, and a solar eclipse takes place when the Earth paes into the Moon's shadow.Elliptical Orbit 轨道
Orbit shaped like a flattened circle.All orbits are elliptical.A circle is a special form of an ellipse.Extraterrestrial 天外来客 Foreign to the Earth.Galaxy 银河
Collection of billions of stars, nebulae, dust, and interstellar gas held together by gravity.Gravity 重力
Attractive force between bodies, such as between the Earth and the Moon.Greenhouse Effect 温室效应
Temperature increase caused by gases(such as carbon dioxide and methane)that prevent the surface heat of a planet from escaping into space.Kuiper Belt 柯伊伯带
Region of the solar system that is home to millions of frozen objects, such as comets.It stretches from the orbit of Neptune to the inner limit of the Oort cloud.Light Pollution 光污染
Brightne of the sky originating in street illumination and other artificial lighting, which impedes the observation of dim celestial objects.Light-Year 光年
Standard astronomical measurement unit equivalent to the distance traveled by light, or any form of electromagnetic radiation, in one
Magnetic Field 磁场
The area near a magnetic body, electric current, or changing electric field.Planets, stars, and galaxies have magnetic fields that extend into space.Magnetosphere 磁气圈
Sphere that surrounds a planet with a magnetic field strong enough to protect the planet from the solar wind.Mantle 地幔
Layer that lies between the crust and the core of a planet.Ma 质量
Measure of the amount of matter in an object.Meteorite 陨石，流星
Rocky or metallic object that strikes the surface of a planet or satellite, where it can form a crater.Milky Way 银河系
The galaxy to which the Sun and the solar system belong.It is visible as a pale band of light that croes our night sky.Nebulae 星云
Clouds of gas and dust in space.Nebulae can be seen when they reflect starlight or when they obstruct light from sources behind them.Nuclear Fusion 核聚变
Nuclear reaction in which relatively light elements(such as hydrogen)form heavier elements(such as helium).Nuclear fusion is the source of energy that makes stars shine.Photon 光子
Elemental particle responsible for electromagnetic radiation.Photons are the most common particles in the universe.Planet 行星
Roughly spherical object made of rocks or gas orbiting a star.A planet cannot generate its own light but reflects the light of its parent star.Polestar 北极星
Polaris, a star that lies near the celestial north pole.Polaris is commonly called the North Star.Over thousands of years, other stars will become the polestar.Proton 质子
Subatomic particle with positive electrical charge.It forms part of the nucleus of an atom.Radio Galaxy 电波星系
Active galaxy emitting energy as both radio waves and light.Most of the radio emiion originates at the core of the galaxy.Space 太空
The medium through which all celestial bodies move.Spectral Analysis 光谱分析
Study of spectral lines that provide information about the composition of stars or galaxies and their redshifts.Spectrum 光谱
The result of dispersing the electromagnetic radiation of an object so that the wavelengths of which it is composed can be seen.Dark lines that originate from elements that are present and punctuate the spectrum at specific wavelengths reveal the composition of the object.Star 恒星
Enormous sphere of gas(generally hydrogen)that radiates light and heat.The Sun is a star.Sunspots 黑子
Dark, relatively cool spots on the surface of the Sun.They tend to be located on either side of the solar equator and are created by the solar magnetic field.Tide 潮汐
The effect of the gravitational pull of one astronomical object upon the surface of another.Ocean tides on Earth are an example.Vacuum 真空
Space occupied by little or no matter.Wavelength 波长
Distance between the peaks of any wave of electromagnetic radiation.Radiation with a short wavelength(such as X-rays)has more energy than radiation with a longer wavelength(such as radio waves).Zenith 顶点
Point in the sky 90° above the horizon(that is, immediately above an observer).Zodiac 黄道带，十二宫图
Twelve constellations through which the Sun, the Moon, and the planets appear to move.NASA 美国航天宇航局
National Aeronautics and Space Administration, the U.S.organization in charge of space exploration.Its headquarters are in Washington, D.C.NASA was created in 1958 by President Dwight D.Eisenhower.Preure Suit 航天服
An airtight, inflatable suit designed to protect the body from low preure at high altitude or in space.A space suit is a type of preure suit.Space Probe 航天测试
Unmanned spacecraft sent to gather information from planets and other bodies of the solar system.Some probes are limited to flying close to a planet.At a preset distance, the instruments are activated to record data.When the probe leaves the planet behind, the instruments are deactivated.Many probes have been sent to land on the surface of a body of the solar system.Such probes have been used to land on the Moon, Venus, Mars, and Saturn's moon Titan.Telescope 望远镜
Instrument for magnifying the image of distant objects.Astronomical telescopes are used for observing the stars, planets, and other celestial bodies.The term is used to refer to instruments that magnify an optical image or an image produced by other types of electromagnetic radiation, such as radio waves.The Hubble Space Telescope is an orbiting telescope that can make observations free from the distorting effects of the atmosphere.
