93 FAQs about the Sun (The Astronomy Cafe)

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 Back to the Astronomy Cafe - 365 of the most popular questions since 1996. Over 1 million page requests!

Beginner:
  1. [Updated]What has the current sunspot cycle been like so far?
  2. [Updated]When can I see the next solar eclipse from North America?
  3. [Updated]Could ancient astrologers have predicted solar eclipses?
  4. [Updated]How did the sun's brightness change during its first few billion years?
  5. [Updated]How old is the Sun?
  6. [Updated]How can I convince children in 3rd grade that the Sun is the center of the solar system?
  7. [Updated]Have astronomers determined exactly how the Sun will change in the next 10 billion years?
  8. [Updated]How large is the Sun's core?
  9. [Updated]When is the Sun predicted to go nova?
  10. [Updated]Is there a correlation between sunspot activity and the weather?
  11. [Updated]Is there any absolute proof that the Sun is not a member of a binary star system?
  12. [Updated]Is the sun shrinking 200 miles/year?
  13. [Updated]How can I find out of there is a solar storm going on right now?
  14. [Updated]What are solar storms and how do they affect the Earth?
  15. [Updated]How long does it take light to get out from the inside of the Sun?
  16. Why didn't Johann Bayer give a name to the Sun like 'Alpha-Prime' or something?
  17. Where did the legend about Ra the Sun god start?
  18. Does the solar wind affect spacecraft the way it does the tails of comets?
  19. If the solar wind can't rearrange the dust on the Moon, why does it blast dust from comets?
  20. What is the rate of mass loss by the Sun from the solar wind?
  21. How bright would the Sun be from the distance of Sirius?
  22. Does water exist on the Sun?
  23. How much energy does the Sun produce in one hour?
  24. Why is the solar corona visible only during a solar eclipse, and not with a sun filter?
  25. How thick is the solar corona?
  26. Is the loss of mass by the Sun sufficient to change the orbits of the planets?
  27. Will the Sun soon be passing through a dust cloud?
  28. Is the Sun shrinking in size?
  29. Is the Sun rotating, or does it always show the same side towards the Earth?
  30. Why is the Sun yellow?
  31. Why doesn't the Sun blow up?
  32. How large is the Sun compared to the earth?
  33. Does the Sun rotate?
  34. What is a solar flare, and are they harmful to humans?
  35. Is the Sun a variable star?
  36. Where can I get the yearly sun spot numbers from 1700 to the present?
  37. What is the speed of the Sun and the size of it's orbit?
  38. On what dates does the Sun pass through the constellations along the Ecliptic?
  39. What is the distance to the Sun from the Earth in miles?
  40. What causes the green flash seen in the setting Sun?
  41. Could you send a space probe directly INTO the Sun, and what would it tell you that us useful?
  42. Will my computer crash because of a solar storm?
  43. How does the solar wind affect the Earth?
  44. How does the solar wind change with time?
  45. How much has the size of the Sun changed in the last few billion years?
  46. What effect do solar flares have on computer chips?
  47. What does the sun look like from the surface of Mars?
  48. What are the major components of the solar wind?
  49. Is the solar wind a problem for astronauts?
  50. If the sun had a white dwarf, what would it be like in our solar system?
  51. What is the farthest likely distance to a companion star to the Sun?
  52. What did people know about the Sun in the 1820s?
  53. How fast and far does the solar wind blow?
  54. What is the composition of the Sun?
  55. How much gravitational force does the Sun produce?
  56. How does the solar wind work?

Intermediate:
  1. [Updated]Why do sunspots vary in an 11 year cycle?
  2. [Updated]Has the solar missing neutrino been solved
  3. [Updated]How do we know what the inside of the sun is like?
  4. How do astronomers measure the temperature of the Sun without going there?
  5. What will become of the Sun after the red giant phase?
  6. How much mass does the Sun convert to energy each hour?
  7. If the Sun causes the solar wind, why is its speed faster by Uranus than near the Sun itself?
  8. Why are sunspots dark?
  9. Do the planets affect the sunspot cycle?
  10. Can you explain why the latest sunrise and sunsets don't happen at the Winter Solstice, but happen on December 7 and January 4?
  11. What is the equation of time?
  12. If the solar corona is so hot, why can't we see it?
  13. What causes the solar wind?
  14. How can astronomers study what happens inside the Sun?
  15. How was the Sun formed?
  16. Our Sun is a yellow star, so why do we speak of white-light spectra when we look at its spectrum with a prism?

Advanced:

  1. How is the solar magnetic field generated?
  2. Why are sunspots dark?

 

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