Astronomy/Eclipses

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Expert: - 9/11/2008


Question
QUESTION: Suppose that instead of being inclined to Earth's orbit around the Sun, the Moon’s orbit was in the same plane as Earth’s orbit around the Sun. In this hypothetical situation, approximately how many solar eclipses would occur each year?
1.0
2.1
3.2
4.12
5.24



ANSWER: Hi Sharmaine,
You would have a solar eclipse at each new moon, or 12 per year.
You would also have a lunar eclipse at each full moon, or 12
lunar eclipses too. Except for the total solar eclipse variety, all other types of eclipses would become...boring and commonplace; no one would watch them.
Clear Skies,
Tom Whiting
Erie, PA

---------- FOLLOW-UP ----------

QUESTION: Thanks you were very helpful but i have one more question?

In reality, the Moon’s orbit about Earth is tilted (by about 5°) with respect to Earth’s orbit about the Sun. As a result, the actual number of solar eclipses that occur each year is approximately

1.0
2.2
3.12
4.24

Answer
The minimum number of solar eclipses each year is 2.
(And also this is the average number, although there can never
be any less than 2).
In 2007 the dates were 3/19 and 9/11
In 2008 the dates were 2/7  and 8/1
In 2009 the dates will be 1/26 and 7/22
In 2010 the dates will be 1/15 and 7/11

2011 is one of those unusual years where there will be
4 solar eclipses, all partial, and the maximum possible in any
one year. See
http://www.mreclipse.com/Special/SEnext.html

{Normally for all eclipses, I send people to the "NASA eclipse homepage", but for some reason, that site is down today, probably
because of Hurricane Ike approaching the NASA space center in
Houston, Texas.)

But for homework purposes, your answer is 2.
Clear Skies,
Tom Whiting
Erie, PA  

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Tom Whiting

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Astronomy has been my hobby/pasttime for over 50 years.  Currently own 3 telescopes, the largest of which is a 30 inch Newtonian truss Dob that is portable.I taught Astronomy/Meteorology at the University Level for 13 years before retiring in 1995. Being retired and home most of the time, I am able to answer all questions relatively quickly, unless it's a new moon weekend with good observing conditions.  No astrology questions please, or questions about alleged UFO picture identifications.

Experience

Experience: Astronomy has been my hobby and study for over 50 years. We currently now own a 30 inch portable telescope (Updated - Pennsylvania`s largest portable telescope). It can be seen on our website at:http://www.velocity.net/~bwhiting and also attend several regional starparties during the year, and have been on 5 total solar eclipse expeditions.

Organizations: President, Erie County Mobile Observers Group for over 15 years.

Publications: Wrote the "Over Erie Skies" newspaper article in our local newspaper for 11 years (1975-86).

Education: Masters Degree- Taught at the University level for 13 years. Retired 20 years -USAF Pilot - KC-135 with 180 combat missions;  Also Eagle Scout, Philmont staff 2 Yrs, Order of Arrow Lodge Chief, Ham Radio (inactive).

Awards: two discoveries: The mini-coathanger asterism in Ursa Minor (the little dipper) And the mini-ladle- another asterism in the bowl of Ursa Minor. Clients: Currently President of the ECMOG as mentioned above.

Education/Credentials
BS  Metallurgical Engineering Grove City College, PAMaster's Degree, Gannon University, Erie, PA Also retired USAF pilot, 20 years.

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