Talking about Astronomy: English Vocabulary List

an object in space that is a mass of ice and dust and when it nears the sun it starts illuminating in the shape of a tail

"A comet appeared in the sky."

"Astronomers observed a bright comet with a long, glowing tail streaking across the night sky."

a piece of rock coming from outer space that passes through the Earth's atmosphere, producing light

"A meteor burned up brightly."

"We watched a brilliant meteor streak across the darkness, a fleeting visitor from outer space."

any of the rocky bodies orbiting the sun, ranging greatly in diameter, also found in large numbers between Jupiter and Mars

"An asteroid flew past Earth."

"Scientists are tracking a large asteroid that is predicted to pass relatively close to Earth next year."

a glowing cloud of gas and dust in outer space, often the result of a star explosion or formation

"A nebula is a cloud."

"The Hubble telescope captured stunning images of a colorful nebula where new stars are being born."

a natural light display in the Earth's polar regions, caused by the collision of charged particles from the sun with atoms in the Earth's atmosphere

"The aurora lights up the night sky."

"The beautiful aurora lit up the night sky with green and pink dancing lights."

(astronomy) the celestial zone in the sky where the sun, moon, and planets appear to move, traditionally divided into twelve equal segments, each associated with a distinct name and symbol

"The zodiac has twelve signs."

"Astrologers believe that the position of celestial bodies within the zodiac at birth influences personality traits."

a planet that is outside the solar system

"An exoplanet orbits another star."

"The discovery of an exoplanet in the habitable zone of its star has generated significant scientific interest."

the displacement of the spectrum of an astronomical object toward shorter wavelengths, indicating motion toward the observer

"Blueshift shows star movement."

"Astronomers observed a blueshift, meaning the galaxy is moving closer."

a small, dense, and faint stellar remnant that is left after a medium-sized star exhausts the nuclear fuel in its core and undergoes gravitational collapse

"A white dwarf is dense."

"After its main sequence life, our Sun will eventually become a white dwarf, a compact stellar remnant."

a highly dense and compact stellar remnant that remains after a massive star undergoes a supernova explosion, consisting almost entirely of neutrons

"A neutron star is very dense."

"The immense gravitational pull of a neutron star makes it one of the densest objects in the universe."

a type of galaxy characterized by a spiral-shaped structure, consisting of a central bulge surrounded by spiral arms that contain stars, gas, and dust

"A spiral galaxy has arms."

"Our own Milky Way is a magnificent spiral galaxy, with its stars arranged in beautiful, sweeping arms."

a type of galaxy characterized by its smooth, nearly featureless brightness profile and ellipsoidal shape, lacking significant spiral arms or disk-like structures

"An elliptical galaxy is smooth."

"Astronomers observed an elliptical galaxy at the center of the distant cluster."

an optical instrument used for analyzing the spectrum of light, separating it into its individual wavelengths to identify and study the components of the light source

"A spectroscope splits light into colors."

"A spectroscope is an instrument that splits light into its different wavelengths so that scientists can study the chemical composition of stars and other distant objects in space."

a galaxy that lacks a distinct, regular shape or structure, often appearing chaotic and asymmetrical

"An irregular galaxy has no shape."

"Unlike spiral or elliptical galaxies, an irregular galaxy lacks a defined structure and often appears quite chaotic."

a mysterious object that some people claim to have seen flying around in the sky and assume that it is a spaceship from another world

"They saw an UFO."

"The pilot reported an unidentified flying object moving silently across the night sky."

an unmanned spacecraft designed to explore outer space, gather scientific data, and transmit it back to Earth

"The space probe explored Mars."

"A space probe designed for atmospheric entry will be destroyed by the heat and pressure if its heat shield fails"

an astronaut from Russia or the former Soviet Union

"A cosmonaut is Russian."

"A cosmonaut is Russia's term for an astronaut"

a layer of charged particles, primarily electrons and protons, held in place around a celestial body by its magnetic field

"Earth has a radiation belt."

"A spacecraft passing through a planet's radiation belt must have its sensitive electronics heavily shielded to survive the onslaught of damaging"

the shift of light waves towards longer wavelengths, indicating the motion of an object away from the observer, commonly observed in the spectra of distant celestial bodies

"Redshift shows galaxies moving."

"Cosmological redshift is not a standard Doppler shift from movement through space"