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Mars looking as big as the moon


jameswade
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Sorry, no. Unless, of course, someone placed a huge lens between Mars and Earth and magnifies the image. You've been around for a few years on earth. Have you ever seen any celestial body as large as the Moon or Sun (each of which appear to be about the same size) other than the Moon or Sun?

 

Excluding any atmospheric distortion the size of an object as seen in the sky is simply a matter of its diameter and distance from the viewer. Two objects might appear to be the same "size" in the sky because they both subtend the same arc in your field of vision. The Sun, obviously, is much larger than the Moon. It's the law of similar triangles. Extend the hypotenuse and opposite side of a triange and place any two different sized objects that fit between the two as a tangent on each side and they appear to be the same size even though they might be far apart along the angle subtended by the hypotenuse and opposite side.

 

 

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You've been around for a few years on earth. Have you ever seen any celestial body as large as the Moon or Sun (each of which appear to be about the same size) other than the Moon or Sun?

The artical i read, whether bogus or not gave a few details that i left out of the post like the position of earth and mars not being this close for since the 1700's, and magnification effect caused by the Earth's atmosphere, I understand that the appearance of size and actual size are two very different things.
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The artical i read, whether bogus or not gave a few details that i left out of the post like the position of earth and mars not being this close for since the 1700's...

James,

The article was bogus in itself and the information in the article is based on an urban legend that is over 7 years old.

 

Mars made the close approach mentioned in the article in August of 2003 not August 2010.

 

But the legend lives on. What the legend leaves out, aside from being incorrect about the year, is that Mars in August of 2003 appeared to be about the same size as the Moon only if you were looking with a 75x telescope. The gist of it was that with a reasonably inexpensive telescope you would have been able to see a lot of details on the Martian surface that you cannot normally see (with the same telescope). However, Mars never appeared as large as the Moon to the naked eye.

 

 

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