Universe and Expansion
The theory that the universe began as a point and has been expanding ever since.
What is the Big Bang Theory?
A huge collection of stars, gas, and dust.
What is a Galaxy?
A large ball of gas held together by gravity with a core so hot that nuclear fusion occurs.
What is a Star?
A cloud of gas and dust.
What is a Nebula?
The distance light travels in one year.
What is a Light-Year?
Leftover energy from the Big Bang.
What is cosmic background radiation?
The spiral galaxy of which the Sun and the Solar System are a part.
What is the Milky Way Galaxy?
A star that fuses hydrogen into helium in its core.
What is a Main Sequence Star?
Formed after helium in a star’s core is gone, it casts off its gases.
What is a Planetary Nebula?
A graph that plots luminosity vs. temperature of stars.
What is the Hertzsprung–Russell Diagram?
An invisible form of matter that does not emit any detectable electromagnetic energy of its own.
What is Dark Matter?
A galaxy exhibiting a central nucleus from which extend curved arms of higher luminosity.
What is a Spiral Galaxy?
A star with a much larger radius and luminosity than a main sequence star of the same surface temperature.
What is a Giant Star?
An enormous explosion that destroys a star.
What is a Supernova?
The best science teacher.
Who is Ms. Miller?
An invisible form of energy that creates a repulsive force causing the universe to expand.
What is Dark Energy?
A galaxy that has a generally elliptical shape and that has no apparent internal structure or spiral arms.
What is an Elliptical Galaxy?
Forms as the core of a giant star no longer supports fusion and the star’s outer layers escape into space, leaving a hot and dense core.
What is a White Dwarf?
An area in space that is so dense that nothing, including light, can escape its gravitational pull.
What is a Black Hole?
All of space and everything in it including stars, planets, and galaxies.
What is the Universe?
A galaxy with no identifiable shape or structure.
What is an Irregular Galaxy?
A cloud of gas and dust in space that develops into a star.
What is a Protostar?
The shift to a different wavelength
What is Doppler Shift?