Stars
The ___________ is the brightness of a star
magnitude
Stars spend most of their life in the _________
main sequence
The ___________ is the galaxy where Earth is located
Milky Way
free points!
free points!
A star exploding at the end of it's lifespan is called a _________
a supernova
The color of light that a star emits tells us it's ___________
temperature
The nuclear fusion of __________ into helium gives off energy
hydrogen
The force that holds a galaxy together is ___________
gravity
T/f
Black holes are nothing but empty space
false
Neutron stars that spin rapidly and produce pulses of x-rays are known as ________
pulsars
The _____________ is a chart measuring a star's brightness and temperature.
HR diagram
The smallest stars are known as __________
red dwarfs
The cluster of galaxies the Milky Way is part of is known as __________
the Local Group
Smaller stars become _________ after they die, since they are not massive enough to become black holes.
neutron stars
The final element that can be produced through fusion inside a star is __________
iron
A protostar is formed through the process of _________, where the force of gravity is pulling gas into a ball.
accretion
The biggest stars are known as __________
supergiants
_____________ galaxies have little structure and relatively little interstellar matter
elliptical
____________________ are at the center of most galaxies.
supermassive black holes
Sba is a barred spiral galaxy with ________ arms
few, little
If a protostar never becomes hot enough to achieve fusion, it is called a ____________
brown dwarf
The balance between gravity pulling a star inwards and fusion pushing a star outwards is known as _____________
hydrostatic equilibrium
The Local Group is part of the __________
Virgo Supercluster
The ______________ of a black hole is greater than the speed of light.
escape velocity
_____________ is when two galaxies collide.
Galactic cannibalism