image credit: Stefan Seip - astromeeting.de; image source; larger image

Astronomy Picture of the Day: Saguaro Moon

This Astronomy Picture of the Day shows a full moon, illuminated by reflected sunlight--for more on this image, see Astronomy Picture of the Day: Saguaro Moon. But we can also see the moon by reflected Earthshine, as shown in this APOD of a new moon.

Compare the pattern of the maria (the smooth dark surfaces on the moon) in these images. The moon rotates with the same part facing Earth--is that consistent with what you see? To learn more about this, and about tides in the solid Earth and moon, see this Bad Astronomy post.

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Moonlight Madness

Do you think you know the phases of the moon? Check out Moonlight Madness to see if you can put the phases in order. For an extra challenge, try the Lunar Phase Quizzer, which forces you to consider how the relative positions of the Earth, sun, and moon produce the phase.

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image credit: NASA/Strategic Defense Initiative Organization; image source; larger image

NSSDC Photo Gallery Moon

Here the moon is illuminated by Earthshine, but this image was captured by the Clementine satellite, in orbit about the moon. Compare the pattern of the maria and craters in the From Physics Research and Physics in Your World images.

Do both of these images show the same side of the Moon? Also, how are the differences in the images consistent with the location of the camera that captured each one? Remember that Clementine was much closer to the moon surface than is Earth.

LCROSS Impact Data Indicates Water on Moon

You may recall last October when NASA, according to popular news media, "bombed the moon." In fact, scientists sent a rocket to impact the Moon's surface in order to produce a plume of debris. A spacecraft flew through the impact debris to collect data, which was sent to Earth for analysis. Check out the LCROSS Mission Overview website for more details and videos of the event.

After analyzing the impact materials using spectroscopy, scientists think they have detected water on the moon. For the full article, see LCROSS Impact Data Indicates Water on Moon.