T Flashcards
Star with masses between 0.5-8 solar masses at birth end up as:
white dwarfs
Stars with masses between 8-20 solar masses at birth end up as
Super nova and neutro stars
Stars with masses above 20 solar masses at birth end up as
Black holes
Describe the proton, proton chain what elements are involved?
Occurs under high temp and pressure in the core of a low mass star. Begins when the star is on main sequence. Converts hydrogen into helium and it is the primary process by which low mass stars make energy
What is the most abundant element from which stars are made
Hydrogen
How is the chemical composition of the suns core different now from what it was 4 million years ago
As the sun gets older, the core in accumulates more helium. It has less hydrogen to burn
Describe Hydrostatic equilibrium
 Internal pressure of the core supporting the sun against the intense inward pull of gravity
In the process of nuclear fusion, some of the mass is converted into
Energy
In the sun, how much mass is converted to energy each second
4 million metric tons of mass
How old will the sun be when he leaves the main sequence?
10 billion years
When does sun gets old and leaves the main sequence
The sun gets larger, surface gets redder and cooler, luminosity decreases and the core fills more with helium
How long does hydrogen burning last in the sun ? how long will helium burning last in the sun?
Hydrogen-10 billion years. Helium-100milliom years
When helium finally begins to fuse in the sun, what is a produce?
Carbon and oxygen
As the core of a low mass star ages it gets hotter but the outer envelope of the star expands and reddens. The star becomes a..
Red giant
What is the planetary nebula? How do they form?
The expanding ring of gas. It occurs when the outer layers of a star are gradually blown away by the hot core
What is a white dwarf
A hot carbon oxygen core of a dead star
Order of a star from early to late
Prostar, main sequence, red giant, planetary nebula, white dwarf
Which star lives the longest
1/10 mass. Stars with the lowest mass live the longest
Why do high mass stats have such short lives compared to low mass stars
Faster fusion rate due to higher gravitational pressure
What is meant by onion skin shells of a high mass star
The layers of different elements undergoing nuclear fusion in stars
What element produced in the core of a massive star marks the end of the line ?when the star begins producing the element how long does it have to live?
Iron. Days
Where do heavy elements come from and basically have a made
Created in supernova explosions. during this explosions extreme conditions, generate high temperatures and pressures allowing for rapid nuclear reactions that produce heavy elements
In a high mass star, if the core is less than three solar masses. It will collapse and become..
Neutron star
In a high mass star, if the core is more than three solar masses. It will collapse and become..
Black hole
What is a pulsar
Periodic flashes of radio energy as the neutro star spins
What are the three possibilities of what star leaves behind when it dies
White dwarfs, Neutron Stars, Black hole
What is singularity
The neutron star is instantly crushed down to an object that is smaller than a proton. A single thing with infinite density
What is the event horizon
Boundary surrounding a black hole beyond wish nothing not even like an escape it’s gravitational pull unless going through speed of light
Schwarschikd radius
The distance from the center of the black hole in which the escape velocity equals the speed of light
What is meant by the point of no return for a black hole
 You would have to travel at  the speed grader than light to escape  and since nothing can travel faster than the speed of light, nothing escape from location
When star start doing this, they enter the main sequence
What starts began undergoing nuclear function in their cores
What object, resides, deep in the core of milky way galaxy and nearly all spiral galaxies
Supermassive black hole