Ask An Astronomer Answer Archive

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  1. Is there water on the moon? If so, can the moon be terraformed?
  2. I have heard that some planets "migrate" in towards their star. How does this work?
  3. What can you tell me about the planet Pluto? Where can I find pictures and information?
  4. Will Neptune and Pluto collide one day? Would that affect the Earth? What if things outside the solar system collide?
  5. I hear that an unknown planet caused perturbations in Neptune's orbit. Is this true?

  6. How many years will it be before Pluto moves outside the orbit of Neptune?
  7. When will the moon's perigee point correspond to its new phase?
  8. When were most of the moon's craters formed, and how big is crater Copernicus?
  9. I know that the second full moon in a month is called a "blue moon". What is the second new moon in a month called?
  10. Who is detecting extrasolar planets, and can I get their raw data?

  11. I read in a magazine that a planet was recently discovered in our solar system. Is that correct? If so, who discovered it?
  12. Do any of the new extrasolar planets have names?
  13. Is there a tenth planet in the solar system?
  14. Are there any pictures of the new extrasolar planets?
  15. Do you have any information on how Palus Somni formed, its composition, or age?

  16. Do you believe that Europa has a subsurface ocean? If so, do you believe that it contains life?
  17. I have heard that we cannot know the masses of the extrasolar planets exactly. If this is the case, how can we be sure that they are planets?
  18. Who are the people working on discovering extrasolar planets? Do they live near New York? Are there any meetings planned which I could attend?
  19. Why do transits of Venus across the disk of the Sun happen in pairs?
  20. How big a telescope would we need to see Earth-like planets around other stars?

  21. Can you tell me about the magnetic field properties of the solar planets?
  22. How was Neptune discovered mathematically?
  23. What did Marcy and Butler discover around Rho Corona Borealis?
  24. I heard that Planet X had been discovered past Pluto. What can you tell me about this?
  25. Has the Hubble Telescope looked at Mars? Did they see aliens in the pictures?

  26. Are there pictures showing how the sun moves in response to the gravitational pull of the planets?
  27. Do other planets have blue skies?
  28. Where do the symbols for the planets come from?
  29. When did Pluto become the most distant planet again?
  30. What is the Earth made of? Is it the only planet with life?

  31. What will happen to the Earth when the planets align in May, 2000?
  32. When did Pluto become the most distant planet in the Solar System again?
  33. How can we talk about other solar systems, if the term "solar" refers only to our sun?
  34. What does an astronomer do? What planets have been explored?
  35. How faint would my telescope have to see in order to see moons around other planets?

  36. When was the last time that the planets were in a line?
  37. Were planets supposedly discovered a long time ago by the "wobble" of a parent star ever shown to be real?
  38. I thought I saw phases on Mars and Jupiter. Is this possible?
  39. Can a conjunction of the planets cause problems for the Earth?
  40. Does a planet's albedo affect its temperature?

  41. Do you have information on Europa?
  42. Will the planetary alignment on May 5 endanger the Earth?
  43. How strong is Pluto's Gravity?
  44. Can a planet collide with another planet?
  45. Is there a quantum law of planetary orbits?

  46. What do we know about Martian weather?
  47. How does a planetary system form?
  48. Is there evidence for a 12th planet in the solar system?
  49. How large would the sun appear to be from the other planets?
  50. Planets move on ellipses with the sun at one focus. What is at the other focus of the ellipse?