Star Calendar
September 2007
Star Calendar Planets:
Mercury will make a poor appearance in the western evening sky in mid-September. It will dash to the eastern morning sky by late October.
Venus will quickly rise into the eastern pre-dawn sky in September and will shine beside Regulus and Saturn by early October. On October 7th the waning Moon will join them.
Mars rises in the middle of the night in the horns of Taurus as September opens. It rises earlier in the evening and brightens as the weeks pass. Mars makes its highest and longest path across our sky on October 1st when it is of Betelgeuse of Orion – best seen in the south at about 6:00 AM.
Jupiter lingers in Ophiucus above Antares and is in the south at sunset as September begins. It slowly accelerates its direct motion and fades eastward toward the setting Sun.
Saturn appears close to Regulus in the eastern morning sky in mid-September. It may be visible under the waning Moon on September 9th and will have a sojourn with Venus a month later.
As seen from the Apollo 15 landing site; central Earth-side of the Moon and about 25° north of the Moon’s equator:
Earth, nearly four times the diameter of the Sun, hangs high in the southern sky. It spins to the right while stars, sun and planets pass very slowly by to the west. Earth does not rise or set, but, over the course of a lunar day (about 29½ terrestrial days), does move clockwise within a round area about 15° in diameter. Earth goes through phases too and is New at local midday and First Quarter a terrestrial week later as the Sun sets. Night is dominated by the gibbous earth; culminating in Full Earth at local lunar midnight. The sky is always black but the Earth-side of the moon’s surface is rarely dark – as it is illuminated by considerable earth-shine all night.
On the 11th at 11:30z the penumbral shadow of the Moon will sweep to the right across South America.
Earth occults Elnath on the 19th at 9: 30z and, along with Mars, caps the horn tips of Taurus three hours later.
A waxing gibbous Mercury complements the beautiful young crescent Earth just below it on the 28th at 16:z
Star Calendar Days:
13 Young crescent Moon after sunset begins Ramadan and Rosh Hashanah
22 Mercury very close to Spica in evening – but difficult to view
23 Autumn Equinox 05:54EDT. Nights lengthen rapidly.
Venus brightest for the year
26 Full Harvest Moon 15:46 EDT
29 Mercury at greatest elongation (26°) from sun
Paul Davis is a former resident of the Threefold Community. He has been a teacher of Celestial Navigation, a Planetarium lecturer, and offered evening Astronomy classes at Sunbridge some years ago. He is glad to continue this column for The Listener in memory of his dear friend Norman Davidson and may be reached at [email protected].
