Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: Earth's shadow



From: SSHS KPHOX <kphox@MAIL.CCSD.K12.CO.US>

This is unclear but I think that what he is saying is something like this:

If the diameter of the earth's shadow were measured at the position of the
moon during a lunar eclipse, it would be smaller than the diameter of the
earth by a distance equal to one moon diameter. Thus the size of the
earth's shadow at the moon's position will cover the entire moon.

The shadow itself is approximately 2.5 moon diameters at the Moon's distance. I think your statement is correct.

Having said that I need to say that Hewitt's language is very unclear. I
don't have that edition to see the page around it or the context.

There's a diagram that I couldn't begin to reproduce here. This description is also in the seventh and ninth editions.


Cheers,
Joe Heafner - Instructional Astronomy and Physics
Home Page http://users.vnet.net/heafnerj/index.html
I don't have a Lexus, but I do have a Mac. Same thing.

This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.