Explosions!
This is the type of stellar explosion that does not have any hydrogen lines
What is a Type I Supernova?
This is how astronomers “detect" black holes
What are the orbits of object around the Black Hole
A main sequence star leaves the main sequence when its core runs out of this element.
This is the only explanation for the extremely regular bursts of pulsars
What is a rotating neutron star?
How many times greater is the Schwarzschild radius of a 12 solar mass black hole than a 6 solar mass black hole?
2x; R_s=2GM/c^2
This is the type of stellar explosion that leaves a neutron star or black hole
What is a Type II Supernova
This is the radius known as the “point of no return” of a black hole, where not even light can escape.
What is the Schwarzschild radius?
A pre-main sequence star emits light because of this process.
What is gravitational collapse?
This what holds up a neutron star from further collapse
What is Neutron degeneracy pressure?
If the parallax of a star is 0.5”, how far away is it?
2 pc; d=1/p
This is the process that creates recurring “explosions” on a white dwarf in a binary system
What are novae?
This type of force, felt by you as you approach a black hole, is stronger for low mass black holes than high mass black holes.
What are tidal forces?
Nuclear reactions release energy as described by this equation.
What is E = mc2?
These were first indirectly detected using binary pulsars
What are gravitational waves?
Star A and Star B have the same luminosity, but Star A is 3x further away than Star B. How many times brighter in our sky is Star B than Star A?
9x; F=L/(4*pi*d^2)
This is the heaviest element created inside stars
What is Iron?
These are theoretical distortions of spacetime that connect different universes
What are wormholes?
This type of star is not massive enough for it’s core to attain a high enough temperature to produce enough hydrogen fusion to support itself, but it does undergo a little bit of fusion.
What is a brown dwarf?
This is a typical period for a pulsars rotation
What is 1 second, or down to millisecond for some pulsars?
Star A has a mass 3 times that of Star B. How luminous is Star A in comparison to Star B? Both are on the main sequence.
(81x brighter; L~M^4)
These are emitted as the core's density increases, and escape from the core, further accelerating the star's collapse; some of them interact with the star's surface, beginning the supernova reaction
What are neutrinos?
Black holes can radiate energy via this process.
What is Hawking radiation/evaporation=creation of electron-positron pairs by borrowing “energy” from the black hole where one of the particles escapes causing the mass to decrease
A white dwarf can attain enough mass from a companion star causing it to explode in a supernova. This explosion is caused by this process.
What is a runaway chain of nuclear fusion reactions of carbon and oxygen-- massive white dwarfs are C and O rich
This the process by which a neutron star can form.
This is the main sequence lifetime of a star 2 times as massive as the sun (whose main sequence lifetime is 10 billion years).
(1.25 billion years; t~M/L~1/M^3)