Chapter 11 Flashcards
Nuclear potential energy (core) / luminosity
10 billion years
E =
Mc^2
Gravitational equilibrium is the perfect balance between what?
Pressure and gravity
What is the radius of the sun?
6.9 x 10^8
109 times the earth
There is a balance within the sun between..
Outward push of pressure and inward pull of gravity
What is the solar (star) system?
A star and all the material that orbits it, including its planets and moons
What is the composition of the sun?
70% hydrogen
28% helium
2% heavier elements
What is the rotation rate of the sun?
25 days (equator) 30 days (poles) -differential rotation
What is the Suns structure?
Chromosome (hot, UV)
Corona (hotter, X-ray)
Hotter objects emit what two things?
- more light at all frequencies per unit area
- photons with higher average energy.
Define fission
Big nucleus SPLITS into smaller pieces (nuclear power plants)
Define fusion
Small nuclei STICK together to make bigger one (sun, stars)
Heavy chemical elements break into small particles and do what?
Generate energy
In low temperatures protons do what?
Repel
In high temperatures protons do what?
Collide
High temperatures enable ___________ to happen in the core
Nuclear fusion
The sun releases energy by fusing __________ nuclei into one ______ nucleus
4 hydrogen
One helium
(Pp chain)
4 protons go in and what comes out?
He nucleus, 2 gamma rays, 2 positrons, 2 neutrinos
Total mass is .7% lower
Energy ________ leaks out of the ________ zone in the form of randomly bouncing photons. How many years?
Gradually
Radiation
100,000 years!
What two things do we compare to learn about the inside of the sun?
Mathematical models vs. observations of solar vibrations and neutrinos
Patterns of _______ on the surface tell us about what the sun is like inside (inner structure)
Vibration
Referred to as helioseismology
Data on solar vibrations agrees with what?
Mathematical models of solar interior
Neutrinos created during fusing ____________ the sun
Fly directly through the sun
How are neutrinos different from photons?
Photons interact with other particles and neutrinos don’t
