The date (in the northern hemisphere) when night and day are nearly of the same length and Sun crosses the celestial equator (i.e., declination 0) moving southward (in the northern hemisphere).
http://scienceworld.wolfram.com/astronomy/AutumnalEquinox.html
Watch before dawn on Sunday. With the waxing crescent moon setting before midnight (on October 20), that means a dark sky between midnight and dawn, or during the best viewing hours for the Orionid meteors. On a dark, moonless night, the Orionids exhibit a maximum of about 15 meteors per hour. These fast-moving meteors occasionally leave persistent trains and bright fireballs. If you trace these meteors backward, they seem to come from the Club of the famous constellation Orion the Hunter. You might know Orion’s bright, ruddy star Betelgeuse. The radiant is north of Betelgeuse. The Orionids have a broad and irregular peak that isn’t easy to predict. More meteors tend to fly after midnight, and the Orionids are typically at their best in the wee hours before dawn. The best viewing for the Orionids in 2012 will probably be before dawn on October 21..
see http://cantonbecker.com/retrograde for details…
For this eclipse totality will be visible from northern Australia and the southern Pacific Ocean.
http://en.wikipedia.org/wiki/Solar_eclipse_of_November_13,_2012
The most populous city to experience totality will be Cairns, which will experience 2 minutes of totality just an hour after daybreak (6:38 am AEST) with the sun at an altitude of just 14°. Norfolk Island, a small pacific island west of Australia, will experience a partial eclipse with a maximum of 98% of the sun obscured at 9:37 am NFT and an altitude of 42°.
Parts of northern New Zealand including Auckland will experience a partial eclipse with over 80% of the sun obscured. Christchurch and points north will see at least 60% of the sun obscured. Maximum eclipse over New Zealand will occur around 10:30 AM NZDT (21:30 UTC).
Parts of central Chile, specifically the Los RÃos and Los Lagos regions from Valdivia (63% obscured) south to Quellón (54% obscured) will see a partial eclipse with over half the sun obscured at sunset, over the coast. Points north up to about Santiago will see the eclipse begin as the sun is setting.