Astronomical terminology

2 1 cm radiation: electromagnetic radiation emitted by cold and thin hydrogen clouds in interstellar space.

3α process: In the nuclear fusion reaction, three helium nuclei are polymerized into a carbon nucleus.

3000 parsec spiral arm: A neutral hydrogen cloud moving away from the center of the Milky Way at a speed of 53 km/s..

A unit of length, 1 angstrom = 1e- 10 meter, usually used to measure the wavelength of light.

Dwarf nova: A celestial body that produces a periodic phenomenon similar to a nova explosion, which may be caused by a white dwarf star in a binary system.

Amino acids: Organic molecules that make up protein.

Dark matter: an imaginary substance theoretically used to fill quality defects.

Dark line spectrum: See absorption spectrum.

Dark nebula: a nebula composed of non-luminous substances such as dust and gas.

Oort Cloud: A cloud cluster located in the outer layer of the solar system and considered as the birthplace of comets.

Barmore spectral line system: The spectral lines of a group of hydrogen atoms, located in the visible and near ultraviolet regions.

White Dwarf: A white dwarf is a star whose core collapses and dies, and its size is similar to that of the Earth.

Million parsec (Mpc): One million parsec.

Semimajor axis: half of the major axis of an ellipse.

Rod spiral galaxy: A spiral galaxy with obvious rod-shaped spiral arms.

The expanding universe: the big bang universe model in the early expansion stage.

Beautiful pearls: sunlight from the undulating surface of the moon during a total solar eclipse.

Umbra: In a shadow, the area where light is completely blocked.

Variable star: A star whose brightness changes periodically.

Standard time: equal to the local average time in the longitude of the central time zone.

Paleolithic soil: soil composed of broken rock fragments.

Wavelength: the distance between two adjacent peaks or valleys, usually expressed by λ.

Maximum wavelength: the wavelength of the spectrum with the largest energy emitted by a complete radiator is only related to the temperature of the object.

Bodie's Law: After calculating the orbits and other parameters of planets (including asteroids) in the solar system, it will

A theory about the origin of the moon.

Irregular galaxy: a huge gas cloud with irregular shape, which contains a large number of star clusters I and II, but has no spiral arms.

Long-period variable star: a variable star with a light variation period of 100 to 400 days.

Superconductor: for some objects, when the temperature drops to a certain extent, the resistance value will drop to zero, in this state.

Dust tail: A tail composed of uncharged substances such as dust.

Equatorial device: a device that can move in the right ascension and right ascension directions.

Declination: Coordinates used in the celestial sphere, similar to latitudes on the earth.

Ozone layer: a layer of the earth's atmosphere, located above the surface 15-30km, with the function of absorbing ultraviolet rays.

Vernal equinox: The point on the celestial sphere where the sun moves from the southern hemisphere to the northern hemisphere and crosses the equator of the celestial sphere. It's about 3 o'clock at this time.

Magnetosphere: The magnetic field of a planet.

Subatmospheric: Carbon dioxide-rich gas escaping from the interior of a planet.

Sub-minimum: the lighter food in the double star variation curve.

Secondary mirror: A mirror in the reflecting telescope that emits light to an observation point.

Spring tide: a huge tidal wave that occurs at a full moon or a new moon.

Big Collision Hypothesis: It is believed that the moon was formed by an asteroid colliding with the earth.

Atmospheric window: the part of the electromagnetic spectrum that can pass through the earth's atmosphere, including radio, infrared and optical bands.

Grand unification theory: a theory that unifies electromagnetic force, strong interaction and weak interaction into one action.

Stripe: A cloud in Jupiter's atmosphere.

Big Bang Theory: The theory that the universe originated from the Big Bang.

Lighthouse theory: the theory that pulsars are autobiographical neutron stars.

Light-year: the distance that light travels in a year.

Meridian circle, local celestial sphere: a great circle in the north-south direction, passing through the zenith and the sky is low.

Horizontal device: a telescope system that can move in horizontal and vertical directions.

Seismic wave: a mechanical wave that can travel across the earth, usually during an earthquake.

The second group of stars: stars with less heavy elements, older, mostly distributed in silver cores and silver rhymes.

The first group of stars: stars with more heavy elements, relatively young, mostly distributed on silver disks.

Radio galaxy: A galaxy that emits strong radio signals.

Electromagnetic radiation: an electromagnetic field propagating in space. Such as light, radio waves

Charge Coupled Device (CCD): Semiconductor photoelectric imaging equipment. Very suitable for astronomical observation.

Electron: a small particle with a unit negative charge.

Electron volt: a unit of energy equal to 1 electron charge unit multiplied by 1 volt.

Solstice: the point on the celestial sphere where the sun is closest to the earth. That's about 65438+ every year on February 22nd, when the northern hemisphere.

Moving galactic nucleus: A galaxy that emits intense radiation.

Doppler effect: the change of spectral line wavelength caused by the motion of the measured object.

Doppler broadening: broadening of spectral lines caused by atomic motion in gas.

Generator effect: the theory that the earth's magnetic field is produced by the molten core.

Emission line: a bright line in the spectrum produced by photons radiated by atoms.

Emission nebula: a gas cloud excited by ultraviolet radiation from a star and emitting light.

Emission spectrum: a spectrum containing emission lines.

Reflective telescope: A telescope system that uses a mirror to focus light on a focal point for imaging.

Reflection nebula: interstellar dust cloud that glows by reflecting starlight.

Van Allen region: Radiation region formed by high-energy ions captured by the earth's magnetic field.

Non-cosmic redshift: Redshift not caused by cosmic expansion effect.

Spectral parallax: a method of analyzing the spectral lines of stars to determine the distance between them.

Split binary star: a star that can be judged by the change of the initial velocity of its sub-stars.

Split hypothesis: A hypothesis about the origin of the moon, which holds that the moon was separated from the earth.

Molecular cloud: A dense interstellar gas cloud containing a large number of molecules.

Closed universe: a model of the universe that thinks there is enough matter to stop the expansion of the universe.

Radiation point: when a meteor shower occurs, the trajectory of the meteor will extend in the opposite direction and converge at one point, which is called radiation.

Radiation stripes (lunar surface): When a meteorite hits the lunar surface, it will produce many white stripes radiating outward from the impact crater.

Radiation pressure: when the surface of an object absorbs photons, it will be subjected to a pressure. Objects floating in the solar system will be affected.

Galileo satellites: The four largest Jupiter satellites discovered by Galileo.

Gauss: the unit of magnetic induction intensity.

Isotropy: Cosmological assumption that the universe is the same in all directions.

* * * Accretion hypothesis: the theory that the moon and the earth formed together.

* * * Vibration: The phenomenon that two periodic motions are synchronized with each other.

Light curve: the curve of brightness changing with time, which is often used to analyze variable stars and eclipsing binary stars.

Luminosity: the total energy radiated by a star in one second.

Photometer: an instrument used to measure the radiation intensity of celestial bodies.

Spectral type: the type of stars in Hubble system. This system takes some characteristic spectral lines and bands in the star spectrum, and this

Photosphere: The visible surface of the sun.

Optical binary star: two stars that look very close, but the actual distance may be far.

Hubble constant: the basic parameter of cosmology, which is used to measure the size and age of the universe.

Hubble's Law: The receding speed of a galaxy is linearly related to its distance.

Helium flash: the polymerization of helium in giant stars.

CAMBRIAN: During the geological period 500-600 million years ago, life on the earth began to appear in large numbers.

Nuclear synthesis: the synthesis of heavy elements inside stars and during supernova explosions.

Herodotus: A statistical chart in which a large number of stars are plotted with their luminosity and surface temperature as horizontal and vertical coordinates.

Black hole: a special celestial body formed by the collapse of massive stars, which has a strong gravitational field.

Blackbody radiation: a hypothetical ideal radiator whose radiation spectrum is only related to temperature.

Black dwarf: White Dwarf after Cooling.

Star density function: a function used to describe the abundance of different types of stars in space.

Star model: a set of parameters describing the state of each layer in a star.

Stellar year: the time required for the sun to pass a star twice in succession on the celestial sphere.

Sidereal day: The Earth's rotation period determined by the position of stars.

Stellar parallax: a method to judge constant distance.

Transverse velocity: the velocity component of a star in the direction perpendicular to the line of sight.

Infrared radiation: electromagnetic waves with a wavelength between visible light and radio waves.

Infrared radiation: electromagnetic waves with a wavelength between visible light and radio waves.

Red shift: when the light source is far away from the observer, the wavelength of the light wave it emits will become longer. This phenomenon is called redshift.

Butterfly chart: a chart used to indicate the distribution of sunspots, which is similar in shape to a butterfly.

Chemical evolution: the chemical process of forming complex molecules on the primitive earth.

Zodiac: The track of the sun in the sky.

Zodiac: The area around the celestial sphere centered on the ecliptic. Seen from the earth

Resolution: The ability of a telescope to distinguish the details of the observed object is determined by the diameter of the objective lens.

Taurus T: A young star surrounded by a lot of gas and dust.

Metal: In astronomy, all elements heavier than helium are called metals.

Perihelion: The point in orbit closest to the sun.

Giant molecular cloud: a gas cloud with very large mass, usually where stars are born.

Supergiant star: A star with high luminosity and low surface temperature, which is very huge (10- 100 times the diameter of the sun).

Distance modulus: the difference between apparent magnitude and absolute magnitude, used to measure the distance of celestial bodies.

Concentricity: a measure of telescope's light gathering ability.

Absolute zero: the lowest temperature (-273. 15 degrees Celsius). The kinetic energy of any particle at this temperature is zero.

Absolute thermal magnitude: the absolute magnitude corresponding to the sum of radiation energy of each band of a star.

Absolute apparent magnitude (MV): The apparent magnitude obtained by placing a celestial body at a distance of 65,438+00 parsec.

Homogeneity: A hypothesis in cosmology that the universe is homogeneous on a large scale.

Kelvin temperature scale: A temperature scale calculated from absolute zero.

Kepler's motion: Motion following Kepler's law.

Archaeoastronomy: Mainly studying ancient astronomy and ancient culture.

Cole black hole: the solution of the gravitational field equation of general relativity, which is used to describe the rotating black hole.

Filter: A device that selectively transmits light waves.

Pulsar: a short-period radio source, which may be a rotating neutron star.

Miller experiment: an experiment that simulates the original earth environment to synthesize amino acids and other organic substances.

Texture: Convection of hot and cold gases on the surface of the sun.

Parsec (pc): The corresponding distance of a star when the parallax obtained by observing the distance between the sun and the earth is one second.

A great circle on the moon or planet that separates day from night.

Bright line spectrum: spectrum containing emission lines. (See: emission line)

Jupiter stripes: Yellow and white stripes parallel to the equator on Jupiter, which are currently thought to be produced by rising gases in Jupiter's atmosphere.

Visual binary: A binary system that can distinguish two sub-stars in a telescope.

Newton: The unit of force.

Accidental meteor: A single meteor that does not belong to any meteor group.

Pashen line system: a group of hydrogen atom spectra in infrared band.

Collision broadening: the phenomenon of spectral line broadening caused by particle collision.

Color index: a numerical measure of the color of a star.

Inverse square law: The law that the intensity of action decays by the square of distance, such as gravity.

Flat solar day: the average time interval between two passes of the sun through the meridian.

Flat Universe: A Universe Model Based on Flat Space-time.

Spectral line profile: the curve of light intensity changing with wavelength.

1,000 parsec (KPC): 1,000 parsec, 3,260 light years.

Chandraseka limit: 1.4 times the mass of the sun, the mass limit of white dwarfs.

Hydrogen ion region: the ionized hydrogen region existing around high-temperature stars.

Autumnal equinox: The point at which the sun passes through the celestial equator from north to south.

Pellet: A spherical glassy object in a meteorite, formed by the dissolution of silicate.

Chondrite: A meteorite containing chondrules and volatiles.

Spherical aberration: Aberration that has nothing to do with the height of the object, but is proportional to the cube of the diameter of the entrance pupil.

Globular cluster: There are tens of thousands to hundreds of thousands of stars in the sphere of dozens of light years.

Total solar eclipse: Total solar eclipse-Seen from the earth, the moon completely blocks the bright surface of the sun.

Annular eclipse: An eclipse in which the sun's photosphere appears in a ring around the moon.

Corona: The darker outer atmosphere of the sun. It is composed of thin, high-temperature ionic gas.

Coronal hole: a dark area on the surface of the sun observed in the X-ray band.

Julian calendar: Calendar compiled in 46 BC.

Zeeman effect: When an atom is in a magnetic field, its spectral line will split into very complex components. This effect is called

Triaxial ellipsoid: a geometric solid sphere with three unequal axes.

Sharo period: Babylonians found that the solar eclipse had a period of 223 moons, which was exactly equal to 18 years.

Flash: A violent explosion on the surface of the sun.

Photoelectric interferometer: refers to a telescope that combines the signals of two or more radio telescopes to obtain more power.

Very Long Baseline Interferometer (VLBI): A method to reduce the distance between radio telescopes so as to see the details of the radio source more clearly.

Glow: When an eclipse occurs, the edge of the sun just emerges from behind the moon.

Stone meteorite iron: a meteorite whose main components are iron and stone.

Rock meteorite: A meteorite whose main component is stone.

Eclipsing binary star: Two members of a binary star system can hide from each other.

Schwarzschild radius: The radius of the horizon around a black hole.

Event horizon: the boundary of a black hole, and observers outside the boundary cannot see the event.

Parallax: the change of the position of the observation target caused by the change of the observer's position.

Apparent magnitude (mv): The brightness of celestial bodies seen by human eyes.

Visual phase, atmospheric tranquility: it is a measure of atmospheric tranquility, which is closely related to the distribution and change of atmospheric turbulence.

Apparent velocity: the speed at which a moving celestial body approaches or leaves the earth.

Excited atom: an atom in which electrons outside the nucleus transition to a high energy state.

Open cluster: A relatively loose aggregate of 10 to 10000 stars.

Binding energy: the energy required to separate electrons from atoms.

Twin Paradox: When one twin brother travels near the speed of light, he will be younger than the other.

Binary star: Two stars that are close to each other and rotate around the same center of mass.

Water hole: in radio observation, the electromagnetic spectrum with the wavelength between 2 1 cm hydrogen line and 18 cm hydroxyl line. With this band,

Speed: A measure of the speed and direction of an object.

Velocity dispersion method: a method to determine the mass of a galaxy by measuring the velocity distribution in the galaxy.

Precession: a slow change in the direction of the earth's rotation.

Solar constant: the total solar radiation measured from outside the atmosphere.

Solar wind: a stream of high-energy particles escaping from the corona, blowing all over the solar system.

Solar Nebula Theory: The theory that the planets in the solar system and the sun are all formed in the same nebula.

Carbon-nitrogen-oxygen cycle: nuclear reactions in stars.

Carbon explosion: the carbon polymerization reaction inside the giant star may be the cause of some supernova explosions.

Trojan asteroid: An asteroid in its orbit at the Lagrangian point 60 degrees ahead or behind Jupiter.

The point on the celestial sphere opposite to the zenith.

Nano:10e-9m.

Nebula: A cloud of dust and gas in the universe.

Zenith: the point on the celestial sphere directly above the observer's head-opposite to the direction of gravity (see the bottom of the sky)

Zenith angle: the spherical angle between the zenith direction and the direction of the measured object.

Celestial sphere: An imaginary sphere with a large radius on which all celestial bodies are located. Used to calibrate the position of celestial bodies.

Celestial equator: An imaginary line that is the intersection of the Earth's equator and the celestial sphere.

Astronomical unit: the average distance between the sun and the earth. It is about1.5e8km. ..

Isotope: atoms with the same number of protons but different numbers of seeds.

Disengagement speed: The minimum speed required for an object to detach from the surface of a star.

Elliptic galaxy: A galaxy with no cantilever and an ellipse outside.

Weidmann pattern: the regional pattern formed in iron meteorites due to the existence of nickel-iron alloy.

Uncompressed density: the mass of a planet without gravity compression.

Temperature: a physical quantity that measures the random motion rate of molecules or atoms inside a substance.

Steady-state theory: the theory that the universe is no longer evolving.

Non-chondrite: A stony meteorite containing no chondrite or volatiles.

Sifo galaxy: an abnormal galaxy, usually with very high brightness, and the brightness fluctuation of the core of the galaxy is very small.

Accretion: solid particles aggregate into larger particles.

Accretion disk: A gas disk formed around a dense celestial body.

Absorption spectrum: a spectrum with absorption lines.

Absorption line: a dark line in the spectrum caused by the absorption of photons by atoms or molecules.

Summer solstice: the farthest point of the sun on the celestial sphere from the earth. That is, around June 22 every year, at this time, the northern half.

Relativistic jet model: a model to explain the superluminal jet phenomenon of quasars

Relative age: the geographical age judged by other characteristics. For example, from relative age, we can judge that it was on the moon last month.

Image intensifier: An electronic instrument used in a telescope to improve the brightness of a star image.

Extinction: Attenuation of light caused by medium.

Achromatic lens: an optical device consisting of multiple lenses, which can eliminate chromatic aberration.

Asteroid: A small celestial body, which is abundant in the asteroid belt between Mars and Jupiter.

Tokamak BL celestial body: A strange celestial body resembling a quasar.

Plagioclase: An ore commonly found in the highlands of the moon, consisting of several silicates.

Nova: A sudden increase in the luminosity of a star may be caused by the explosion of a white dwarf star in a binary system.

Magnitude: a standard for marking the brightness of celestial bodies. The larger the magnitude, the darker the star.

Interstellar reddening: The phenomenon that the star image turns red due to the blue light scattered by the interstellar medium.

Interstellar medium: gas and dust existing in interstellar space.

Interstellar absorption line: a dark line produced in the spectrum of stars due to the absorption of interstellar gas.

Interstellar absorption line: a dark line produced in the spectrum of stars due to the absorption of interstellar gas.

Constellation: A symbol similar to a constellation used to mark a group of stars.

Star Association: A group of stars that are not clustered but have the same motion trend.

Constellation: a name used to mark a group of stars. Usually use mythical characters.

Planetary Nebula: A gas shell excited by the radiation of a central high-temperature celestial body, which looks like a planet.

Basalt: Volcanic rock formed by magma.

Spiral arm: a spiral galaxy consisting of bright stars, bright clouds, gas and dust, extending from the center of the galaxy to the edge of the galaxy.

Pressure broadening: spectral line broadening caused by atmospheric pressure of stars.

Occlusion: The phenomenon that one celestial body covers another.

Liquid metal hydrogen: the state of hydrogen under high pressure, with good conductivity.

General principle: the hypothesis that the laws of physics on the earth can be applied to any corner of the universe.

Tuning fork diagram: a classification method of galaxies-galaxies are divided into elliptical galaxies, spiral galaxies and irregular galaxies.

Silver halo: the low-density outer layer of silver halo.

Gravitational wave: the propagation mode of gravitational energy predicted by general relativity.

Gravitational redshift: wavelength increase caused by photon leaving gravitational field.

Hidden areas: those areas around the milky way galaxy that cannot be seen by other galaxies because of the dust blocking in Hanoi.

Cosmic rays: high-speed particles that break into the earth's atmosphere.

Cosmology: the study of the laws, origins and evolution of the universe.

Protostar: A gas cloud that is collapsing to form a star.

Primitive atmosphere: the earliest atmosphere on the earth, consisting of materials that were originally solar nebulae.

Primitive black hole: A small black hole formed in early BIGBANG.

Prominence: A violent explosion on the surface of the sun.

Apohelion: The point in orbit farthest from the sun.

Moon Sea: The lowlands on the surface of the moon.

Mass-luminosity relationship: For general stars, the greater the mass, the greater the luminosity.

Eclipse: A phenomenon that occurs when the moon enters the shadow of the earth.

Transition: the movement of electrons from one energy level to another.

Meteorite: A meteor that falls to the ground but does not burn out in the atmosphere.

Halo: A spherical region in the outer layer of a spiral galaxy.

Periodic nova: a star that erupts every few years.

Dirty snowball theory: accepted theory of comet structure.

Cepheid variable: a variable with a light change period of 1-60 days, and its light change period has a definite relationship with luminosity.

Refractive telescope: a telescope system that refracts light through a lens to image.

Zhelun Cloud: Irregular galaxy near the Milky Way, visible in the southern sky.

Needle: A needle-like projectile located on the chromosphere of the Sun.

Oscillating universe model: A model of the universe that thinks that the universe will oscillate back and forth between the Big Bang and the Big Squeeze.

Seismograph: An instrument for recording seismic waves.

Closing point: the turning point of a star from the main sequence to the red giant on the Herro diagram.

Proton: hydrogen nucleus, nucleus with unit positive charge.

Compact stars: celestial bodies formed by collapse, such as white dwarfs, neutron stars, black holes, etc.

Neutron: An uncharged nucleus with a mass close to that of a proton.

Neutron star: A high-density celestial body composed almost entirely of neutrons.

Gravity acceleration: acceleration caused by gravity, usually used to describe the magnitude of gravity on the surface of a star.

Zhouguang diagram: a diagram showing the period-luminosity relationship of Cepheid variable stars.

Active optics: an optical system controlled by a computer, which can achieve the best imaging effect by adjusting system parameters at any time.

Main sequence: The banded area from the upper left to the lower right on the hero map concentrates 90% of the stars.

Transfer clock: A device that enables a telescope to point at a star.

Ultraviolet: electromagnetic wave with a slightly shorter wavelength than visible light and a slightly longer wavelength than X-ray.

Self-sustaining star formation: a mechanism that can be used to explain the existence of spiral arms, through which the forming star can

Adaptive optics: a telescope imaging system that can partially eliminate atmospheric disturbances.

Self-motion: changes in the position of celestial bodies on the celestial sphere.

Brown dwarf: a low-light star with insufficient mass to trigger a nuclear reaction.