Nuclear Reactions
In the core of a main sequence star, hydrogen fuses into ___________, producing gamma rays.
Helium
About how old do we think the Sun is?
About 5 billion years old
When the Sun dies, will it leave behind a white dwarf or a neutron star?
White dwarf
What is the object at the center of a black hole called?
Singularity
Who came up with the theories of Special and General Relativity?
Albert Einstein
What do we call the type of fusion that takes place in one or more layers outside the core of a star?
Shell fusion
What two types of "pressure" hold up a main sequence star against gravitational collapse?
Gas pressure and radiation pressure
What do we call neutron stars that are spinning very fast and periodically hit us with a beam of light, like a lighthouse in space?
HINT: We originally called them LGM sources
Pulsars
What do we call it when too strong of a tidal force stretches you out?
Spaghettification
General Relativity states that mass warps the fabric of _______.
Spacetime
In the proton-proton reaction (fusing two hydrogens together), in addition to the gamma rays that are produced, there is a difficult-to-detect particle produced as well. This particle moves very fast, has very little mass, and is neutral in charge. What is the name of this particle?
A neutrino
Between a 5 M☉ star and a 20 M☉ star, which star has a shorter lifetime?
The 20 M☉ star
What will white dwarfs eventually turn into?
HINT: None of them exist yet
Black dwarf
What is the escape velocity at the event horizon of a black hole?
The speed of light, or "c"
The bending of light as it travels through the warped spacetime near a massive object is called...
Gravitational lensing
In addition to fusion, we discussed another type of nuclear reaction that involves large nuclei splitting apart, releasing energy in the process. What is this other type of nuclear reaction called?
Fission
Does a high mass star spend more of its lifetime fusing hydrogen in its core, or fusing carbon in its core?
More time fusing hydrogen
What is the upper mass limit for a white dwarf?
1.4 solar masses aka the Chandrasekhar Limit
What type of black hole has the weakest tidal force at its event horizon?
A supermassive black hole
How many dimensions do we humans experience as we move through the universe.
4. 3 of space and 1 of time
What do we call the fusion reaction that uses carbon, nitrogen, and oxygen as catalysts to fuse hydrogen into helium?
The CNO Cycle
A Type II supernova occurs in a massive star mere moments after it begins fusing which element in its core?
Iron (Fe)
What force/"pressure" keeps a white dwarf from collapsing due to gravity?
Electron degeneracy pressure
Material that spirals into a black hole can form a hot, bright disk around it. This is called the ________ disk.
Accretion disk.
Special relativity says that an object traveling at relativistic speeds will appear shorter (along the direction of travel) to an outside of observer. What do we call this "shortening"?
Length contraction