Expert: Harry Hayfield - 7/31/2004

Question
hello.. i have many questions about eclipse cause i have an upcoming report.. thanks for your big help!
so here it goes.. Which is more frequent among the phases of the three solar eclipses and why? how about in the three lunar eclipse? The moon is smaller than the sun but why do total solar eclipse do happen instead the annular solar eclipse alone? Why is it not safe to look at the total solar eclipse with the unaided eye and yet the sun is completely covered by the moon? How de we know when an eclipse will happen? How frequent is the solar and lunar ecluipse, how many solar/lunar eclipse happens each year?
thanks again!

Answer
Glad to be of help!

Question 1: Which is more frequent among the phases of the three solar eclipses and why?

Actually, they all occur about the same amount of time, but in terms of which most people are likely to see that would be a total solar eclipse (simply because more people are aware of a total eclipse than a partial or annular)

Question 2: how about in the three lunar eclipse?

Again, that would be a total lunar eclipse for the same reasons

Question 3: The moon is smaller than the sun but why do total solar eclipse do happen instead the annular solar eclipse alone?

Ah yes the old prespective trick. This answer is very long winded so if you e-mail me at harry_hayfield@beeb.net I will provide a very long winded (but simple to understand) answer

Question 4: Why is it not safe to look at the total solar eclipse with the unaided eye and yet the sun is completely covered by the moon?

That's a common misconception. Whilst it is not safe to look at the sun DURING the eclipse, once totality is reached you can look to your heart's content. The only guideline is look towards the sun after the first diamond ring and away after the second diamond ring

Question 5: How de we know when an eclipse will happen?

That's down to the Babylonians. They worked out that eclipses happen about once every 18 years or so (and soon realised that these eclipses followed a pattern)

Question 6: How frequent is the solar and lunar ecluipse, how many solar/lunar eclipse happens each year?

It can vary quite wildly, but the average is once every six months for a solar eclipse (with a lunar eclipse 14 days prior or after a solar eclipse)