Origins
Galaxies
Stars
Vocabulary
Celestial Objects
100
A major event that is thought to have occurred around 13.5 billion years ago, important to the current theory of the universe's creation.

What is the Big Bang?

100

The spiral galaxy the Earth and Sun are located in.

What is the Milky Way?

100

The swollen phase a main sequence star goes through at the end of its life.

What is a red giant?

100
The actual brightness of an object such as a star.
What is luminosity?
100

A massive collection of dust, stars, and gas bound together by gravity.

What is a galaxy?

200

The commonly accepted theory of the universe's origin which states that galaxies have been moving apart from each other since the birth of the universe.

What is the Big Bang Theory?

200

A large and common galaxy with an elliptical appearance.

What is an elliptical galaxy?
200

The phase a star spends most of its life in, our Sun is this type of star.

What is a main sequence star?
200

The brightness of a star as seen from Earth.

What is apparent magnitude?

200
An object that forms after the death of a massive star, so dense that light can't escape its gravity.

What is a black hole?

300

A large cloud of gas and dust in space, known as the birthplace of stars.

What is a nebula?
300

A galaxy with a nucleus and a disk with spiral arms.

What is a spiral galaxy?

300

A small, low mass star with a long life.

What is a red dwarf?

300
A testable idea or explanation that leads to scientific investigation.

What is a hypothesis?

300

A region in the sky with a recognizable star pattern.

What is a constellation?

400

A now-disproven theory that claimed the universe stayed the same over time.

What is the Steady State Theory?

400

A small galaxy with no identifiable shape.

What is an irregular galaxy?

400

The final phase a low mass star goes through before dying.

What is a white dwarf?
400

An apparent shift in the position of an object when viewed from different locations.

What is parallax?

400

A spherical collection of stars bound together by gravity.

What is a globular cluster?

500
The scientists who created the Steady State Theory.

Who were Fred Hoyle, Herman Bondi, and Thomas Gold?

500

The closest large galaxy to the Milky Way, set to collide with the Milky Way in about 4.5 billion years.

What is Andromeda?

500

The final phase a massive star goes through before exploding in a supernova.

What is a red supergiant?

500

A graph that shows the relationship between a star's surface temperature and absolute magnitude.

What is a Hertzsprung-Russel diagram?

500

The form a large mass star takes after a supernova if it doesn't collapse into a black hole.

What is a neutron star?