This theory states that about 13.7 billion years ago, the universe began with a huge, fiery explosion followed by its even expansion everywhere.
What is the Big Bang Theory?
100
The galaxy in which we live.
What is the Milky Way?
100
This is the first step in the formation of a star?
What is an increase in temperature?
100
In 5 billion years, the sun is said to become one of these.
What is a giant star?
100
This dense collapsed core of an object in space, contains such a strong gravitational pull that no matter or energy can escape from it, including light.
What is a black hole?
200
If a star is moving toward Earth, its wavelengths of light are said to be this.
What is compressed?
200
This type of galaxy is somewhat shaped like a football and can contain trillions of stars.
What is an elliptical galaxy?
200
This is the second step in the formation of a star.
What is fusion?
200
After becoming this type of star in 5 billion years, the sun is said to eventually become one of these.
What is a white dwarf?
200
This assembly of stars and their planets, gas, and dust extends over many thousands of light-years and forms a unit within the universe.
What is a galaxy?
300
This type of shift occurs when a star is moving away from Earth and its wavelengths are stretched or elongated.
What is the Red shift?
300
The most common type of galaxy, these galaxies tend to look like pinwheels, with long arms winding toward a bright bulge at the center.
What is a spiral galaxy?
300
This term refers to a group of stars that form a pattern.
What is a constellation?
300
The sun is the closest star to this planet.
What is Mercury?
300
This continuous and distinctive band of stars appears on plots of stellar color versus brightness as a prominent diagonal band that runs from the upper left to the lower right.
What is the main sequence?
400
This model proposes that the universe was always as it is now.
What is the Steady State theory?
400
These galaxies appear misshapen and lack a distinct form, often because they are within the gravitational influence of other galaxies close by.
What is an irregular galaxy?
400
This graph shows the relationship between absolute magnitudes and temperature of stars.
What is the H-R diagram?
400
These appear on the surface of the Sun and look dark because of the lower temperatures near it.
What are sunspots?
400
This term is used to refer to apparent change of the frequency of a wave due to the relative motion between the source and the observer and can be observed for any type of wave.
What is the Doppler shift?
500
According to this idea, the universe expands and contracts repeatedly over time.
What is the Oscillating model?
500
This galaxy is a spiral galaxy approximately 2.5 million light-years (2.4×1019 km) from Earth making it the nearest major galaxy to our own Milky Way.
What is Andromeda?
500
Hydrogen atoms fuse to form helium in order to generate or release this.
What is energy?
500
This term is used to describe the visible surface of the Sun.
What is the photosphere?
500
This term is used to describe the cluster of galaxies that includes the Milky Way among others.