Star Cycles
This is the first stage of a star's life, formed when gas and dust collapse under gravity.
Stellar Nebula
Scientists believe the universe began with this massive expansion event about 13.8 billion years ago.
Big Bang Theory
When light from distant objects appears more red than expected, this is called
Red Shift
This star is at the center of our solar system
Sun
Our galaxy is called the _______________ _______________
Milky Way
This type of star fusion converts hydrogen into this element in the core.
Helium
In the first few minutes after the Big Bang, the universe was filled with this extremely hot, dense state of matter.
Plasma
Red shift occurs because distant galaxies are moving _______________ from us.
Away
The four planets closest to the Sun are called _______________ planets.
Terrestrial
Galaxies are classified into three main shapes: spiral, elliptical, and _______________.
Irregular
When a massive star runs out of fuel, it explodes in this dramatic event.
Supernova
This leftover radiation from the Big Bang can still be detected today as background radiation.
Cosmic Background Radiation
This scientist first observed that distant galaxies show red shift, proving the universe is expanding.
Hubble
This largest planet in our solar system has a Great Red Spot.
Jupiter
The nearest major galaxy to the Milky Way is the _______________ Galaxy.
Andromeda
This extremely dense object forms when a star's core collapses and not even light can escape.
Black hole
The Big Bang theory explains why the universe is still doing this today.
Expanding
The faster a galaxy moves away from us, the more its light is shifted toward this end of the spectrum.
These icy objects with long tails orbit the Sun in highly elliptical paths.
Comet
Most galaxies have one of these extremely massive objects at their center.
Black Hole
Stars with masses similar to our Sun will eventually become this type of small, hot, dense star.
White dwarf
This scientist created the Big Bang Theory.
Georges Lemaître
Red shift is caused by this effect, which changes the wavelength of light from moving objects.
The doppler effect
This region beyond Neptune contains many small icy bodies and dwarf planets like Pluto.
Kuiper Belt or ____ belt
A group of galaxies held together by gravity is called a galaxy _______________.
Cluster