The Sun
Properties of Stars
A Star is Born
A Star Dies
Vocabulary
100

The cooler spots on the sun.

What are sunspots?

100
what all stars are primarily made of
What are hydrogen and helium?
100
A cloud of gas and dust primarily composed of hydrogen and helium. Known as the birthplace of stars.
What is a nebula?
100
when stars start to burn this gas, it is an indication of the beginning of the end
What is helium?
100
the violent explosive death of an aging star
What is a supernova?
200
eruptions of hot gas trapped in the strong magnetic fields of the sun's chromosphere
What is a prominence?
200

The outer atmosphere that can usually only be seen when there is a solar eclipse.

What is the Corona?

200
Gravity causes the gas and dust of a nebula to start clumping together. Astronomers call this process of adding atoms to the center of a protostar this
What is accretion?
200
Low-mass stars will shrink and end up becoming this. An extremely small hot star with a huge density.
What is a white dwarf?
200
the measure of the total energy radiated by a star in one second
What is luminosity?
300

Our sun is in this phase.

What is Main Sequence?

300

on this scale the smaller the number the brighter the star.

What is the magnitude?

300
a balance between gravity pulling atoms toward the center of a star and gas pressure pushing heat and light away from the center.
What is equilibrium?
300
In this short phase in the life cycle of a star there is expansion of the outer layers of the star and cooling as the star exhausts the fuel in the core. Once the fuel for fusion is gone, the balance between pressure and gravity is upset. The core shrinks. The gasses surrounding the core are “puffed off.”
What is a red giant?
300
a graph that illustrates the relationship between the average surface temperature of stars and their absolute magnitude
What is a Hertzsprung-Russell diagram?
400

The intense release of energy released due to sunspots.

What are solar flares?

400
A star's most important property. This determines its luminosity and spectral type at each stage of life.
What is mass?
400
a protostar that never had enough dust and gas accreted (roughly 0.05 solar mass) to achieve a temperature hot enough to ignite fusion.
What is a brown dwarf?
400
The highest mass stars have cores that shrink to a point. On the way to total collapse they may momentarily create a neutron star and the resulting supernova rebounds in an explosion. Gravity finally wins. Nothing holds it up. Space is so warped around the object that it effectively leaves our space creating this
What is a black hole?
400
The total energy emitted from a star, based off of size and temperature.

Absolute Brightness

500
The lowest layer of the solar atmosphere. This is the visible part of the sun where sunspots and granules are found.
What is the photosphere?
500

This is determined by the star's temperature.

What is the Star's color?

500
Stars live out the majority of their lives in this phase. Once achieving nuclear fusion, stars radiate (shine) energy into space.
What is main sequence?
500
in a large-mass star, the star's collapse increases the internal temperature of the star causing it to explode
What is a supernova?
500

Process where hydrogen nuclei are fused together to form helium nuclei. Extra mass that is lost is released in the form of energy.

What is nuclear fusion?

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