a graph relating the surface temperatures and absolute brightnesses of stars
A large cloud of gas and dust in space, spread out in a immense volume. Where stars are "born."
When gravity pulls some of the gas and dust in a nebula together and there is enough mass to form a star (nuclear fusion has not begun)
A huge cloud of gas that is created when the outer layers of a red giant star drift out into space
The blue-white hot core of a star that is left behind after its outer layers have expanded and defined out into space. The death of low to medium-mass stars
The brilliant explosion of a dying supergiant star. Stage after main sequence for high mass stars.
The small, dense remains of a high-mass star after a supernova explosion (less than 5 solar masses, with a diameter of only 20 km)
An object whose gravity is so strong that nothing, not even light, can escape (formed after supernova with 5 or greater solar mass remaining)
3 main characteristics used to classify stars
temperature (color), mass, and absolute magnitude (also diameter size, stage in life cycle)
main sequence star, 4.6 billion years old, middle of life, medium sized, yellow- 6,000 degrees celsius, center of our solar system
How are mass and the length of a star's life related?
Inversely related. The greater the mass, the shorter the life span. Small mass stars have the longest life spans.
When a low mass star runs out of hydrogen fuel, what happens next?
The outer layer expands and becomes a red giant.
After a supernova explosion, if the core remaining is greater than 5 solar masses, what is formed?
a black hole
Two pieces of evidence that astronomers use as evidence of the presence of a black hole:
1) x-rays detected coming from rotating hot gas near a black hole. 2) The effect of gravity on nearby stars and objects.
Where are main sequence stars located on a H-R Diagram?
Diagonally across the diagram from bright and hot to dim and cold.
Where are supergiants located on a H-R Diagram?
top (very bright), and broad range of temperatures (blue, white, yellow and orange)