a. Suppose the surface temperature of the Sun were 9,000 K instead of 6000 K. How much more thermal radiation would the Sun emit? What would happen to the Sun's wavelength of peak emission? What would happen to life on Earth?
b. A sunspot appears only 80 percent as bright as the surrounding photosphere. The photosphere has a temperature of approximately 5780 K. What is the temperature of the sunspot?
c. Go to the website: https://solarscience.msfc.nasa.gov/predict.shtml. Where are we in the Sunspot cycle right now? When is the next solar maximum or minimum expected? Recent or live images of the Sun can be found here: https://sdo.gsfc.nasa.gov/data/ are there currently many spots? What is a magnetogram? Why do astronomers want pictures of the Sun at different wavelengths - what can be seen?