What is a carbon star?
it's a white dwarf
What is a pulsar?
a varying radio star that emits radiation in pulses. A rotating neautron star, remnant of a supernova explosion
What creates the magnetic field that surrounds a pulsar?
The rotation that occurs in our core
A star rotating with charged particles
Know the different fusion cycles that takes place in small and large stars?
small: proton fusion
large: proton fusion, helium fusion, carbon fusion
Difference between a white dwarf and a massive-star supernova?
White Dwarf: Type Ia-no prominent lines of hydrogen seen and orgin is a white dwarf
massive-star Supernova: Type II-contains prominent hydrogen lines, results from explosion of a single star
What is the Algol paradox?
Why is it important?
a detached binary system made up of two main sequence stars that share mass between them.
It's important because the bigger star will become a red giant and the smaller star will become a blue giant.
What is an accretion disk?
a rotating disk of gas orbitng a star
What is the basic definition of a black hole?
a part of space caused by a big mass star explosion. Nothing can escape a blackhole, a point of gravity
Know what the fusion byproduct is for the final fusion cycle in the different stars.
brown dwarf: less than .08
helium white dwarf: .08-.25
carbon oxygen white dwarf: .25-8
Iron: 8-12
Could our sun ever become a nova or white dwarf supernova?
No, the Sun is too small to go nova or supernova, it'll enter the red giant stage then collapse into a white dwarf
Which particle degeneracy pressure stops gravitational collapse in a White Dwarf?
In a Neutron Star?
Electron degeneracy for a white dwarf
Neutron degeneracy for a neutron star.
What is the Chandrasekhar limit?
1.4Msun
Difference between Schwarzchild radius and The Event Horizon?
Schwarzchild radius is from the center of a blackhole to the event horizon.
Event Horizon is where you see the outline of the blackhole
Event Horizon is where velocity exceeds the speed of light
Why does the presence of iron indicate the impending demise of a star?
It can not fuse any further
Why are white dwarf supernova good distance indicators?
Since they're Type Ia they are bright and are consistent in their max energy output
Why is there an upper limit to the mass of a white dwarf?
electron degeneracy can't withstand the pull of gravity resulting in the star to collapse
What does Nova mean?
A star that suddenly increases in brightness then slowly fades back to its original lumininosity
How does a black hole affect spacetime?
The black hole has enormous amounts of mass that cause curvature in spacetime
What is happening inside a star while it expands into a subgiant?
Nuclear fusion has stopped, the core contracts and the outer shells expand
What causes x-ray bursts and x-ray busters?
x-ray bursts: caused by an increase in temperature that fuse hydrogen resulting in rapid nuclear burning that is released in a flash of x-rays
x-ray busters: are neautron stars (novae) in a binary-star system
What happens when a white dwarf reaches the mass of 1.4Msun? Why?
It becomes a supernova because the degeneracy pressure is so great the electrons move at the speed of light causing the white dwarf to explode.
What is a Type I a supernova?
an exploding white dwarf, a white dwarf supernova
Why are white dwarfs called white dwarfs?
They're called white dwarfs because their small, extremely dense,hot, and the light is white
Explain how a star can get larger while the core gets smaller, what happens to the core as it gets smaller?
Gravity takes over and the core contracts which causes the core to heat up and expel energy that pushes the layers out
Evidence that gamma- ray bursts originate from beyond the Milky Way Galaxy?
The wavelengths and afterglows pin point their source to distant galaxies