The
Moon – Then & Now
The View from GalileoÕs
Telescope
On November 30, 1609 Galileo
started observing and sketching the Moon.
He was probably not the first person to look at the Moon through a
telescope, but Galileo had made himself a telescope that was much better than
the others, and he could see the MoonÕs surface in much more detail. Galileo
described the surface of the moon as being uneven and rough and Òcrowded with
depressions and bulges.Ó In his sketches,
like the one below, he shows clearly that the line between the light and dark
sides of the Moon that looks so straight with the unaided eye, is in fact
ragged from the long shadows cast by mountain ranges and (as we know now)
craters. In fact, the surface of the Moon was pretty much like the surface of
the Earth!
Above: One of GalileoÕs first sketches of
the surface of the Moon. Image Credit: Octavo Corp./Warnock Library)
Before GalileoÕs
observations the Moon was thought to be a perfect, smooth sphere (the light and
dark regions that can easily been seen by eye were unexplained blemishes on a
smooth surface). The perfection of
the heavens set the planets apart from the imperfect Earth. But now the Moon was revealed to have
very Earth-like mountains and valleys.
If the Moon, and maybe the other planets, have Earth-like features,
could not the Earth be a planet too?
Above: Archive MicroObservatory image of the
Moon. How does the phase compare
with the image you obtained?
What
did you See?
How does the Moon appear in
your image taken by MicroObservatory? Did you have a chance to step outside and
see the Moon with your own eyes last night? If so, how does your image compare with your memory of how
the Moon looked? Is GalileoÕs sketch an accurate representation of the actual
Moon, or do you think he took Òartistic licenseÓ to emphasize the major
feastures?
To see your image of the
Moon more clearly, you may want to open it in our MicroObservatory image
processing software. Click here to
find out more.
The
Moon - 400 years later
The Moon is the only place
in the Universe, beyond Earth where human beings have set foot. The Apollo missions in the 1960s and
1970s gave us tremendous insight into the history and structure of the
Moon. The lighter regions of its
surface are over 4 billion years old.
The landscape is covered in craters that have been preserved because
there is no atmosphere, and therefore no weathering, of the surface. The darker regions, called Maria (Latin
for Sea) because they look like oceans, are actually vast plains of volcanic
lava, although the last volcanic eruptions on the Moon ended over three billion
years ago.
Above: Do you recognize this? ItÕs the other
side of the Moon! (Image credit: NASA)
When Galileo looked at the
Moon through his telescope, his first though was how Earth-like the features
appeared. The similarity goes
beyond anything that Galileo could have conceived. Evidence now shows that the
Moon was once part of the Earth, and that an impact between the young Earth and
another planet in the early Solar System ripped away a huge amount of the
EarthÕs outer layers which would later cool and re-solidify as the Moon.
Above: Humans on the Moon. Can you spot the running astronaut?
(Image credit: NASA)
A quarter century after
humans last walked on the Moon, NASA is preparing for the next generation of
lunar exploration. In late 2008
NASA will launch the Lunar Reconnaissance Orbiter, with the objectives to
finding safe landing sites, locate potential resources and hazards, and test
new technologies in preparation for the return of humans to the Moon.
For more information on the
Apollo Mission, go to:
http://www.nasa.gov/mission_pages/apollo/index.html
For more information on the
Lunar Reconnaissance Orbiter, go to: