Universe is all of time and space and its contents. It includes planets, moons, minor planets, stars, galaxies, and other types of celestrial bodies.

star is a luminous sphere of plasma held together by its own gravity.

ight-year is the distance light travels in one year.

Galaxy- a system of millions or billions of stars, together with gas and dust, held together by gravitational attraction.

Dark matter is an unidentified type of matter comprising approximately 27% of the mass and energy in the observable universe that is not accounted for by dark energy, baryonic matter (ordinary matter), and neutrinos.

NEBULA a cloud of gas and dust in outer space, visible in the night sky either as an indistinct bright patch.

Parallax is a method of measuring the distance to nearby objects in space

big bang theory. : atheory in astronomy: the universe originated billions of years ago in an explosion from a single point of nearly infinite energy density

dark energy is an unknown form of energy which is hypothesized to infuse all of space, tending to accelerate the expansion of the universe. Roughly 73% of the Universe.

Redshift, a shift toward longer wavelengths of the spectral lines emitted by a celestial object that is caused by the object moving away from the earth.

MILKY WAY GALAXY the spiral galaxy containing our solar system

BLUE SHIFT a shift toward shorter wavelengths of the spectral lines emitted by a celestial object that is caused by the object moving towards from the earth.

celestial body is any natural body outside of the Earth's atmosphere. Easy examples are the Moon, Sun, and the other planets of our solar system.

ELLIPTICAL GALAXY: SPHERICAL OR FLATTENED DISCS THAT CONSIST OF MAINLY OLD STARS

IRREGULAR GALAXY: GALAXY WITH NO DEFINITE SHAPE AND USUALLY FORMS WHEN TO GALAXIES COLLIDE TOGETHER

METEROIDS: CHUNKS OF ROCK THAT MOVE AROUND WITHIN THE SOLAR SYSTEM

METEORITE: CHUNKS OF ROCK FROM SPACE THAT STRIKES OR HIT A PLANET OR MOON

METEOR: CHUNCKS OF ROCK FROM SPACE THAT BURNS UP WHEN ENTERING A PLANET'S ATMOSPHERE

ASTEROIDS: ROCKY BODIES THAT ORBIT IN THE ASTEROID BELT LOCATED BETWEEN MARS & JUPITER AROUND THE SUN

MOON: A ROCKY BODY COVERED WITH CRATERS THAT ORBITS AROUND PLANETS.

Comet is an icy body that releases gas or dust. They are often compared to dirty snowballs, though recent research has led some scientists to call them snowy dirtballs. HAVE 2 PARTS: HEAD & TAIL

PLANET: A CELESTRIAL BODY MOVING IN AN ELLIPTICAL ORBIT AROUND A STAR.

ELLIPTICAL SHAPE: Refers to the shape of an ellipse, which is an elongated circle, stretched into anoval.

ROTATE: spin or move or cause to move in a circle around an axis or center.