Quiz 04/02/2013

1. How do we know what is happening inside the Sun? Mathematical models agree with observations of solar vibrations and solar neutrinos.
2. What causes solar activity? The stretching and twisting of magnetic field lines near the sun's surface causes solar activity.
3. How does solar activity vary with time? By the activity rising and falling in 11 year cycles. 
4. Do neutrinos have mass? Yes
5. Do we get neutrinos from the Sun? Yes
6. What did Ray Davis got the Nobel prize for? For pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos.
7. How long is the sunspot cycle? 22 years
8. Why are sunspots cooler? Sunspots are regions of strong magnetic activity, which inhibits convection from below. The combination of the up-and down movement of gases within the Sun's convective zone and the movement of the sun's rotation produces magnetic fields. These magnetic fields slow down activity in the convective zone. Slower convection means that less gas is transferring heat from the core of the sun to the photosphere. Therefore, regions of the photosphere near strong magnetic fields are up to 3000 degrees Celsius cooler than surrounding areas.
9. Are there magnetic fields in the Sun? Yes
10. What is the solar wind? Solar wind is a flow of charged particles from the surface of the suns.