Download Name: _ Period: _______ Date: _______ Astronomy Vocabulary To

Name: ___________________________________________________________ Period: _________ Date: _________
Astronomy Vocabulary
To help you learn the up and coming vocabulary for the unit, students are to APPLY the vocabulary terms in
different ways to assist in long term memory to be applied in labs in the future. In the box provided, draw neatly and
color appropriately, and image that resents the meaning of the term. No words or numbers can be used in the image.
This “cheat sheet” will then be placed in your notebook as a resource but will also be used on your vocabulary quiz.
Due Date: __________________
Quiz Date for Cheat Sheet: _________________
1.
Cosmology- The study of the universe, including its current nature, origin and evolution, based on
observation and the use of theoretical models.
2. Heliocentric Model- The ancient model of the earth, first created by Copernicus, that stated our planets
revolved around the sun.
3. Geocentric Model- The ancient model of the universe, first created by Ptolemy, that stated the earth was
the center of the universe and all other object (including the sun) revolve around the earth.
4. Quasar- star-like, very bright, extremely distant object is unlike other stars in that it emits radio waves and
are further and brighter than most galaxies.
5.
Astronomical Unit- a unit of measure used to measure distance of objects in our solar system. (1 AU=
the distance from earth to the sun `90 million miles.)
6.
Gravity-The force that attracts objects.
7. Electromagnetic spectrum-all types of electromagnetic radiation arranged according to wavelength and
intensity.
8. Hubble’s Law- The observation that the farther away the galaxy is, the faster it is moving away.
9.
Parallax-apparent positional shift of an object caused by the motion of the observer.
10.
Apparent Magnitude-how bright a star appears to be; usually dimmed by distance and earth’s
atmosphere.
11.
12.
Absolute Magnitude-The actual brightness of a star based on its size and stage it the life cycle.
Light-year- the distance that light can travel in one year moving at 186,000 miles/second.
13.
Big Bang theory- The initial explosion that resulted in the formation and expansion of the universe.
This explosion release hydrogen and helium which make-up 99% of our known universe.
14.
Nebula- A large cloud of dust and gas in space, where stars form.
15.
Supernova- a massive explosion of a dying star.
16. Supercluster-gigantic threadlike or sheet-like clusters of galaxies that is hundreds and millions of lightyears in size.
17.
Nuclear fusion- The combing of two atomic nuclei to produce a single larger nucleus and much more
energy. (Ex: hydrogen in the core of the sun join together to create helium and massive amounts of energy.)
18.
Hertzsprung-Russell Diagram- a graph that demonstrates the positive relationship between
temperature and color/brightness. As temperature increases, brightness increases.
19.
Blackhole- an object with gravity that is so enormous the nothing can exist, not even light can escape.
20.
Redshift- A shift of light towards the red end of the electromagnetic spectrum of light to show that an
object is moving AWAY from Earth. (Blueshift would show the object is moving towards Earth).
21.Dark Matter – An unknown substance, thought to be made of some new sub-atomic particle, which is
believed to make up the majority of the mass in every galaxy.
22. Dark Energy – A hypothetical force/energy that is causing the known universe to expand at an accelerating
rate.
23. Background Radiation – The leftover debris, dust, and radiation (energy) from the initial big bang
explosion that is found in every area of our universe.
24. Eccentricity – ratio of the distance between the foci to the length of the major axis; defines the shape of a
planet’s orbit (more elliptical or circular).
25.
Planetisimal-space object built of solid particles that can form planets through collisions and mergers.
26.
Dwarf planet- a small object that has little mass and gravitational pull that revolves around the Sun but
stays within its “neighborhood”.
27.
Terrestrial planet- the small, rocky inner planets of our solar system (Mercury, Venus, Earth and Mars)
28.
Jovian planet- The large, gaseous and massive planets of the outer solar system. (Jupiter, Saturn,
Neptune, Uranus)
29.
Asteroids- very large (size of a country or continent) chunks of rock that are large enough to feel the
gravitational pull of the Sun but not large enough to be a planet. (usually found in the Asteroid Belt between
Mars and Jupiter)
30.
Comet- a loose collection of ice, dust, with a small rock core and a tail of debris that orbits the Sun.
31.
Meteor- A streak of light in the sky produced by a meteoroid burning up in the Earth’s atmosphere.
(referred to as a “shooting star”)
32.
Meteoroid- a meteoroid that withstands the burning through the Earth’s atmosphere and lands on the
Earth’s surface.
33. Synchronous Rotation – The state in which a planet or moon’s rotation and revolution are equal.
34.Retrograde motion- The apparent backward movement of a planet in the sky.
35. Satellite- an object, otherwise known as a moon, that revolves around a planet.
36. Orbit- the PATH that an object takes around another object.
37. Revolution- the TIME it takes for an object to go around another object.
38. Rotation- the spinning of an object on its axis.
39. Solstice – A point in the year when the north or south poles is pointed directly at the sun at noon.
40. Equinox – Point in the year when Earth’s axis is perpendicular to the sun’s rays at noon. (neither pole points
to the sun)