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Library of Past Questions

Earth and Moon

  • We no longer answer questions on this topic, to concentrate our limited resources on questions on space based astrophysics and closely related areas (see this page for more explanation).
  • Check out the resource links. These are the sites we used to point to in answering your questions.
  • Browse through the library of questions below. We may have already answered your questions.

Resources for this Topic

  1. StarChild: The Solar System

  2. The Nine Planets (

  3. The Exploration of the Earth's Magnetosphere (

Library of Past Questions and Answers

    Calendar and Seasons

  1. When is the Sun at it's highest point in the sky?

  2. What is the altitude of the Sun on Equinoxes and Solstices?

  3. What sequence of events is necessary for the completion of one month on our calendar?

  4. How did Gauss calculate the date Easter will fall on?

  5. How does the tilt of the Earth's axis affect the seasons?

  6. Why is winter colder than summer?

  7. What causes the time asymmetry of sunrises and sunsets?

  8. What is Sidereal time?

  9. When does the new millennium start?

  10. Can science confirm the missing day referred to in the Bible?

  11. Do eggs only balance on end during the Spring Equinox?

    The Earth

  1. Is there a source that one can peruse and purchase high altitude pictures of a particular area on earth?

  2. Why does the Earth spin on its axis?

  3. How fast does the Earth rotate?

  4. What is the direction of rotation of Earth? Of our galaxy?

  5. How fast does the Earth travel around the Sun? Why, when the Earth moves at such a high rate of speed, don't we feel it?

  6. What effect do the tides have on the Earth's rotation rate?

  7. Why is Earth the only planet with an ozone layer? And why is it the only one with life and water?

  8. What if the hole in the ozone layer of Earth got really big?

  9. What are meteorites?

  10. How many meteorites enter our atmosphere a day?

  11. Did an asteroid ever hit Earth?

  12. Are we going to be hit by an asteroid?

    Radiation and Particles Around the Earth

  1. What are the effects of the solar cycle on the earth?

  2. How do sunspots affect the Earth?

  3. Are aurorae caused by solar flares?

  4. Is there any great danger to Earth from Solar Flares?

  5. What is the cause of Geomagnetic Storms?

  6. Can you tell me about the radiation in the Van Allen Belt?

  7. What are the boundaries of the South Atlantic Anomaly?

  8. Does the South Atlantic Anomaly rotate?

  9. What causes the South Atlantic Anomaly?

    The Moon

  1. Why does the moon appear during the day?

  2. Is there any night time on the Moon?

  3. Is there a dark side of the Moon?

  4. Why is the Moon's revolution and rotation period the same?

  5. How often do lunar eclipses happen?

  6. What do the Moon rocks Apollo brought back tell us?

  7. Besides water, what else is in the ice found on the moon?

  8. What are some of the substances found on the Moon?

  9. Does the Moon have a molten core?

  10. Can you provide me with the latest theories on the origin of the Moon?

  11. Does the Moon's phase affect the crime rate?

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Acting Project Leader: Dr. Barbara Mattson
All material on this site has been created and updated between 1997-2012.

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