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How light of sun reach at moon?

by Hepic
Tags: light, moon, moonearthsun, reach
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Dec24-13, 02:41 AM
P: 113
Quote Quote by Bob View Post
Is this possible?
I am wonder that too.
Can answer Bob's question?
Dec24-13, 04:00 AM
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davenn's Avatar
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Quote Quote by Hepic View Post
I am wonder that too.
Can answer Bob's question?
his drawing is out of proportion

your question has been answered :)

have your google searched eclipses yet ?

Dec24-13, 08:40 AM
tfr000's Avatar
P: 127
Quote Quote by adjacent View Post
Since the moon always come between the Earth and the sun during new moon,Why not? At least the shadow should get to somewhere on the Earth.
The Moon does not always come between the Earth and Sun at new moon. The Moon's orbit is not in the same plane as the Earth's orbit around the Sun. It is close, but there is enough of an angle between them to cause "misses". You need to do some web searching for "eclipse" - there are websites that explain it much better than we can here.
Dec24-13, 09:54 AM
P: 12,081
Quote Quote by russ_watters View Post
3. Because the inclination isn't large compared to the Earth's apparent diameter (2 degrees) to the moon, you can have several at least partial eclipses a year; not just one or two. Extra ones are a month apart.
4. #3 is also why you have many more lunar eclipses than solar eclipses (the sun's and moon's apparent diameters to Earth are only 0.5 degrees).
#4 depends on the interpretation. While the shadow of earth is larger, the earth is also a larger target to catch the smaller shadow of moon. The required alignment is the same in both cases, both for partial and full eclipses (at least if we neglect annular eclipses).
For a given location on earth, lunar eclipses are much more frequent as they are visible from half the surface on earth, while solar eclipses are visible within a very narrow band only, but the frequency of "one of those happens somewhere" is the same.

In the next 10 years, there will be 20 lunar eclipses 8 of them total) and 20 solar eclipses (6 of them total).
I'm not sure if two lunar eclipses with a distance of 1 month are possible, but a lunar eclipse and a solar eclipse 2 weeks afterwards (or vice versa) is common.

Quote Quote by Bob View Post
Is this possible?
Dec24-13, 12:43 PM
P: 22,315
I'm having a doubt, but lets check:

They go by decade, so lets look at 2011-2010:

Solar Eclipses: 24
Total: 6

Lunar Eclipses: 23
Total: 9

And solar eclipses can indeed happen a month apart just like lunar eclipses, such as in June and July of 2011. So yeah, with a solar eclipse it is a smaller shadow but bigger target, so those effects must cancel out. You are indeed correct that I fooled myself by thinking about the visibility issue (and therefore publicity issue) with solar eclipses only being visible at certain places while lunar eclipses are visible everywhere.

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