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The Moon approx. 9 days after new.   
Taken at the Port Macquarie Observatory with the 355 mm  reflecting telescope at the prime focus.
 
 The photograph shows the two most conspicuous craters on the Moon, Tycho & Copernicus.
Tycho, named for Tycho Brahe, the Danish astronomer.and copernicus for Nicholas Copernicus.
 
 Tycho, top right hand corner, is very bright and has a tremendous system  of rays that extend out from its edge for hundreds of kilometres in all directions.  The crater is approx 90 kilometres in diameter.
 
 Copernicus is approx in the centre of the photograph, just off the terminator line (day and night).
 
Copernicus is also about the same diameter as Tycho.  Copernicus also has a ray system, but not as extensive as that of Tycho. It is very prominent at full moon.
 
Both craters have mountain peaks.

PORT MACQUARIE ASTRONOMICAL ASSOCIATION INC

THE MOON

 

                                                                             Jim Daniel

 

The Moons craters  tell an  interesting story about the history of our solar system.  Long ago, meteoroids by the millions, hit the Moon with  tremendous force, gouging out most of the craters we see there.  Most of the meteoroids were used up very quickly, and so the bombardment slowed down dramatically.  When portions of the Moons surface melted, the old craters were erased.  So we can now tell almost at a glance whether a part of the Moons surface is young or old.  A young surface has few craters, because there are relatively few meteoroids left to make fresh craters, but an ancient surface will be nearly covered with craters.

           When astronauts visited the Moon, they brought rock samples back to the Earth for analysis.  From this it was found that even the youngest rocks on the Moon are actually extremely old.  This tells us that no new rocks have been produced on the Moon for a very long time.  On the Earth, however, many geologic processes are still going on, producing new rocks and fresh surfaces.

Although the Moon was a geological active body once, it is now a nearly dead object in space.

              Port Macquarie Astronomical Assoc. Inc.