Constellation of the Month: Aquarius, the Water Bearer
"When the moon is in the Seventh House
And Jupiter aligns with Mars
Then peace will guide the planets
And love will steer the stars.
This is the dawning of the Age of Aquarius. . ."
So went the song from the tribal rock opera "Hair." The songwriter was a bit premature, as the astrological Age of Aquarius will not begin for another 600 years, when the Vernal Equinox moves into the constellation of Aquarius. Nevertheless, in our November sky, the constellation of Aquarius can be found about halfway up in the south as it gets dark.
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Click the map for a larger image. About halfway up in the southern sky you can find this month's constellation, Aquarius. This is one of the constellations of the Zodiac. Members of this group form a band around the sky where the classical planets (and the Sun) are always found, but this month, there are no planets in our evening sky. They are either too near the Sun, or in the morning sky. |
Greek mythology has Aquarius causing a great flood around 1500 BC. Following his father's advice, Deucalion and his wife Pyrrha built a great boat and stocked it with provisions. The flood came and while everyone else drowned, the two floated on the world-encompassing sea for nine days and nine nights. Finally, the waters started to recede, and the boat settled on Mount Parnassus. The two survivors left the boat and walked about as the waters receded. Being the only two people, how were they going to reclaim the Earth? They asked an oracle and were told "throw over your shoulders the bones of your mother."
Deucalion guessed that "mother" referred to Mother Earth, and the "bones" were stones. So they would pick up stones as they walked along and throw them over their shoulders. After a while, they looked back and saw that each of the stones they had tossed had become a person. The stones Deucalion tossed had become men and those Pyrrha had thrown became women. So Aquarius, who had brought the flood, also brought a rebirth of life on Earth.
In western Aquarius you'll find one of the smaller and fainter globular clusters from Messier's catalog, M72. Unlike many other Messier objects, M72 has no shape-inspired name. This little cluster is one of the more distant globular clusters. It is on the other side of the center of our galaxy, some 300,000 trillion miles away (53,000 light years). Even at this distance, it is still easily seen with a telescope at ninth magnitude, so it must be an intrinsically brighter globular. Unlike many other globular clusters, M72 does not have a bright core. Instead, its central area is a rather uniform brightness.
Globular clusters are older than our galaxy, having formed from clumps of dust and gas in the same giant cloud that formed our galaxy. Since these clumps collapsed to form hundreds of stars before the galaxy collapsed into its pancake shape, they are scattered above and below as well as in the galactic plane. The stars in these globular clusters are all bound together by their mutual gravity. Since the stars of M72 have not had a chance to become more tightly packed in the center of the cluster, it must be a relatively young cluster.
The Planets for November 2006
Mercury zips from east of the Sun last month to west of the Sun this month for an appearance in our morning sky. Beginning Nov. 10, Mercury will be visible in the east-southeast from about 5:30 a.m. until the morning sky gets too bright. The Messenger of the gods will reach its farthest angular distance from the Sun on Nov. 19, when it will be 12 degrees above the east-southeast horizon 30 minutes before sunrise. It then turns back toward the Sun. At mid-month, Mercury will be only 8.9 seconds of arc across at magnitude 1.2.
Watch the Skies Nov. 5, 5:58 am —Full Moon Nov. 8, 12:12-5:10 p.m.—Transit of Mercury Nov. 11, Midnight—Moon near Pleiades Nov. 12, 10:45 a.m.—Last Quarter Moon Nov. 17, 2 p.m.—Leonid Meteor Shower peaks Nov. 20, 3:18 p.m.—New Moon Nov. 25, 6 a.m—Mercury farthest west of the Sun Nov. 27, 11:29 p.m.—First Quarter Moon |
Saturn rises around midnight and is visible the rest of the night. In eastern Leo, the Ringed Planet is 18.1 seconds-of-arc across, growing slowly larger as the Earth approaches it. The rings are now 41 seconds-of-arc across, tilted up only 12.4 degrees with the southern face showing. The three other classical planets, Venus, Mars and Jupiter, are too near the Sun to observe.
When Mercury passes between the Sun and Earth, it will happen during the magic three-day interval around Nov. 8. This is one of the two times a year that Mercury's orbit crosses directly between the Earth and Sun. When Mercury is actually near this point at this time, as this year, then Mercury will cross the face of the Sun as it moves from the east to west side of the Sun. This is called a transit.
The first transit of Mercury since 2003 will occur on Nov. 8. The transit starts at 12:12 p.m. when Mercury first touches the edge of the Sun. Two minutes later, it is completely on the Sun's disc at the south-southeastern edge. Moving west-northwestward, Mercury will pass closest to the Sun's center at 2:41 p.m. By 5:08 p.m., Mercury will start moving off the Sun's western edge. By 5:10 p.m., the transit will be over. The next transit of Mercury will be May 9, 2016.
To observe this transit, you will need a telescope equipped with a special solar filter that fits over the front of the telescope. Do not look at the Sun through a solar filter that fits over the eyepiece and never look directly at the Sun with or without a telescope. A transit is much like a partial solar eclipse, and you can find more information on safe solar eclipse observing in NASA's "Eye Safety During Solar Eclipses" page online at
sunearth.gsfc.nasa.gov/eclipse/SEhelp/safety2.html.
So get your solar filters ready, and "keep watching the sky"!
An amateur astronomer for more than 35 years, Bert Stevens is co-director of Desert Moon Observatory in Las Cruces.