Flares are caused by magnetic disturbances in the lower atmo- sphere of the Sun. (T/F)

The velocity of the solar wind is roughly 400 km/s. How long does it take to travel from the sun to Earth?

Assume that the solar wind causes the Sun to lose mass at a rate of 2 x 10’ kg/s. If you assume the wind is emitted a constant rate, estimate the time (in units of Gyr =Gigayears = 10° years) that it will take the entire Sun to evaporate via its solar wind emission. (Of course, the rate won't be constant throughout the lifetime of the Sun---this is just a rough estimate to understand the timescale associated with this process.) [Hint: you need to look up a number and do several unit conversions; this is a *rate* problem. Enter your answer as an integer or decimal, NOT in scientific notation.]

Sunspots appear dark because they are hotter than the sur- rounding gas of the photosphere. (T/F)

Why does nuclear fusion only take place in the Sun’s core?

Why are observers more likey to see aurorae in Canada than in Florida ?

Use Stefan's law to calculate how much energy is emitted per unit area by the photosphere of sun 5800-K.

The density and temperature in the solar corona are much higher than in the photosphere. (T/F)

If a contracting prostar is 3 times the radius of the sun and has a temperature of 1680 k how lumminous will it be relative to the sun? Use luminosity radius temperature to the relation. The surface temperature of the sun is 5800k