Starry Skies Above Santa Monica
March 7-15, 2001

Mirek Plavec
meritus Professor of Astronomy, 
UCLA

   Sun, Moon and Planets
   The Sun continues to move upward through Aquarius (the Water Bearer), and is now only 3.3 degrees below the equator. On Sunday, March 11, it will pass, at local noon, over Machala in Ecuador, Belem in Brazil, over Nairobi in Africa, and over Palembang on Sumatra. For us, the Sun will rise at 6:08 (a gain of 10 minutes per week) and set at 5:58 p.m. (6 minutes later than a week ago) – so a net gain of 16 minutes of daylight time.
   The Moon will become Full on Friday night, March 9, and will be seen between the constellations of Leo and Virgo. Then the Moon will recede into the night, and on the morning of March 15 (Thursday) it will shine close to the planet Mars in Scorpius.
   Venus is still very prominent every evening, visible fairly high above the western horizon already by 6:30 p.m. or so. It still shines quite long, and on Sunday, it sets by 8:33 p.m. If you compare the time of setting with the previous Sunday, you will notice that Venus sets 26 minutes earlier than last Sunday, while the Sun sets 6 minutes later. The fact that Venus is returning to the Sun (as seen in our sky, i.e. diminishing its angular deviation eastward of the Sun) is beginning to show, still rather inconspicuously. This is partly due to the fact that Venus is currently projected fairly high above the ecliptic, so that it lies 17 degrees higher to the north than the Sun. As a consequence, Venus still remains prominent and fairly high in the sky shortly after sunset – but not for long! Actually, on March 7, Venus will stop in its eastward motion among the stars, and begin to move back, westward. This is, of course, only a projection effect -– in reality, Venus will continue to move calmly eastward in its orbit around the Sun. The apparent halt, followed by the "retrograde" (westward) motion with respect to the stars, is the consequence of the celestial race between the Earth and Venus. At the moment, we are still a bit ahead of Venus, but Venus, moving faster and in a shorter orbit, is beginning to catch up with us – and will succeed on March 30. On that day, the Earth, Venus, and the Sun will lie on the same straight line. However, Venus will be invisible, because it (she?) will be projected directly in the direction of the Sun, and lost in the Sun’s glare. 
   When the sky gets still a bit darker, you will have no problem in finding the bright Jupiter to the southwest of the zenith. Saturn, fainter (but still first-magnitude "star") is not far to the west of Jupiter. Both planets now move eastward among the stars, but at a snail’s speed, so you will find them pretty much at the same place where they have been for weeks. Currently, they are fairly close to each other, Jupiter still between the Pleiades and Aldebaran, and Saturn not far from Jupiter, a few degrees to the west. It is the motion of the Earth, as reflected in the apparent motion of the Sun, that changes their visibility: after 11 p.m., both planets disappear below the western horizon. 
   The only planet visible in the morning hours is therefore Mars, which rises deep in the southeast shortly after midnight. Mars, being much closer to the Sun and to us than are Jupiter and Saturn, appears to move definitely faster with respect to the stars. It has just passed a few degrees above its competitor in color, the red supergiant Antares, and will be crossing the boundary between Scorpius and the next "sun sign" constellation, Sagittarius. Actually, astronomical maps show that Mars is presently projected into the constellation of Ophiuchus (The Serpent Bearer).