Thursday, September 22, 2011

The Gate of Cancer

























The moon has been rising later and later (as it always does due to the mechanics explained in this previous post) and it will soon be overtaken again by the sun to create another new moon (on the morning of the 27th).

Over the next few mornings, it can be seen rising in the east before sunrise, and will be an important signpost that can help point the way to the planet Mars in the constellation Cancer near the constellation Leo in the predawn sky. To see an excellent diagram of the eastern horizon as it appears 90 minutes before sunrise, check out this link to Sky & Telescope's discussion of the celestial events through the 24th.

Note that the sun is now coming up later and later each morning, which should help you get up before the sun and get to a place where you can witness this predawn show (you don't have to rise quite as early as you did in the middle of summer in order to see the eastern constellations before the sun). Morning twilight is now beginning around 0626 and sunrise around 0651 for observers at latitude N 35°.

In the diagram from Sky & Telescope linked above, you will see that the moon helps point the way to Mars, and that the great constellation of Leo the Lion is rising up not far away. While not indicated on the diagram from Sky & Telescope, Mars itself is in the constellation of Cancer the Crab, the faintest of all the zodiac constellations. You can see where Cancer is situated in relation to Leo and to Hydra by looking at the illustration at the top of this post -- from that, you can go back to the Sky & Telescope illustration, which does depict both Leo and Hydra (note that Leo is rising upwards before sunrise, so that the illustration at the top of this blog post must be rotated counterclockwise in order to orient it to the predawn sky).

Cancer is very faint and difficult to make out, but if you get used to where it is located, then you can keep an eye out for it as it rises earlier and earlier and eventually marches through the wee hours of the morning. When it does so, you can use your binoculars to look for the Beehive cluster, marked in the illustration above. The Beehive is designated as Messier Object M44 by astronomers, and is also known by the Latin name Praesepe, or "the manger."

Giorgio de Santillana and Hertha von Dechend tell us in Hamlet's Mill that Cancer (which, as can be seen from the illustration above, is also near to the constellation Gemini) was thought of as the gate of one end of the Milky Way band (opposite to the Scorpion and Sagittarius, who guard the other end of the Milky Way).

They relate that the important ancient philosopher Macrobius (AD 395 - 423) provided a record of the ancient belief that the souls of the departed ascend into the Milky Way by way of the Scorpion and Sagittarius (and Capricorn, which is adjacent to Sagittarius), and that eventually, they descend again to be reborn through the "Gate of Cancer" (de Santillana and von Dechend, 242, citing Macrobius' commentary on the Dream of Scipio).

It is quite significant that the authors of Hamlet's Mill find this very same tradition preserved in various forms (all recognizable) among the Indians of North America and Central America as well as among the Maya, and also among the Polynesians (see 243-244).

The Milky Way is well worth viewing through binoculars and it is very visible now (especially with the moon mostly out of the way for late evening viewing). Then, in the morning, rise up early and bring your binoculars again to look for the stars of Cancer between Leo and Gemini and above Hydra, and take in the waning crescent moon and the planet Mars. With a little practice, this end of the Milky Way -- near the important the Gate of Cancer -- can become as familiar as the other side that is guarded by the Scorpion and Sagittarius.