Scheduled air date: 2003 Apr 07-13

Because the planet Mercury's orbit is so close to the Sun, it is usually hidden
from view by the Sun's glare. During the month of April, however, it will
be visible low in the western sky shortly after sunset. On April 16th,
Mercury will be at greatest eastern elongation—the point in its orbit
which appears farthest eastward of the Sun as seen from Earth—and should
therefore be quite easy to see.
(Shown about an hour after sunset on April 16th for mid-northern
latitudes.)

On the same night, we'll be treated to the closest Full Moon of the year. Because
the Full Moon of April 16th will be about 30000 miles/49000 km closer than the
farthest Full Moon of the year—which occurs on December 8th—it will appear both
larger and about 30% brighter than the latter.
If you wish to view illustrations for other episodes, please see our Star Gazer Illustrated directory.
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Illustrations on this page were created using
TheSky Astronomy
Software, an advanced desktop planetarium program designed for Windows. Copyright © 1999-2006 by Software Bisque, Inc. |