Scheduled air date: 1999 Jun 21-27

Because Mercury's orbit keeps it close to the Sun, it is only visible to the Earth-based
unaided eye for short periods a few times each year, and then only just after sunset, or
just before sunrise.
(Shown from above the Solar System, illustrating the relative positions of the inner
planets at the end of this week.)

Looking toward the Westwith a low, flat horizonjust after it begins to get
dark this week, and next, Mercury can be seen to the lower-right of Venus. These two
planets and the star Regulus form a nearly straight line.
(Shown about one hour after sunset for mid-Northern latitudes.)
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. |