Frost Moon

Been a while and a little late (both my fault), but here is another installment of Gordon’s monthly full moon email ( Thanks again Gordon!).  This is also my first tablet posting, so we shall see how that works out… Enjoy!

The next full Moon is on Wednesday, November 28, 2012. The Moon will be “opposite” the Sun at 9:46 am EST on Wednesday morning. In fact, the Moon will be so “opposite” the Sun from the Earth that it will pass through the partial shadow of the Earth (called a penumbral eclipse). From the Washington, DC area we will not be able to see this eclipse, as the Moon will be below the horizon. Farther west in North America, the eclipse will start before moonset, but the partial shadow of the Earth causes a gradual shading of the Moon difficult for the eye to detect. If you are in the western pacific, Australia, or eastern Asia, you may see the Moon slightly darkened and reddened by the shadow of the Earth, as the peak of the eclipse will be straight overhead in the Pacific about halfway between Japan and the island of New Guinea.

The Moon will appear full for about 3 days around the peak of the full Moon and the eclipse, from Monday evening, November 26, 2012, through Thursday morning (possibly even Thursday evening), November 29, 2012. Suitably celebratory celestial attire is encouraged in honor of the full Moon.

As the last full Moon of Fall, this full Moon is sometimes known as the Moon Before Yule or the Frost Moon. Europeans call this full Moon the “Moon before Yule” (Yule is an old northern European winter festival that is now associated with Christmas). A Native American name for this full Moon (as reported in the Farmer’s Almanac) is the Frost Moon, as frosts begin to occur towards the end of Fall.

This is also Kartic Poornima. According to Wikipedia: “Kartik Poornima (Kartik purnima) is a Hindu holy day celebrated on the full moon day or the fifteenth lunar day of Kartik (November–December). It is also known as Tripuri poornima and Tripurari Poornima. It is sometimes called Deva-Diwali or Deva-Deepawali – the festival of lights of the gods. The Kartik Purnima festival also coincides with the Sikh festival of Guru Nanak Jayanti.”

As for other celestial events between now and the full Moon after next…

* On Thursday, November 29, 2012, the planet Jupiter is quite bright and drawing close to being “opposite” the Sun. Look for the full Moon and Jupiter near each other, rising in the east at sunset and riding high in the sky as the night progresses. The bright star Alderbaran will be nearby as well.

* For the Washington, DC area, Friday, November 30, 2012 through Thursday, December 13, 2012 will be he earliest sunsets (i.e., darkest evenings) of the year. Rounded to the nearest minute, sunset will be at 4:46 pm EST across these dates.

* Saturday, December 1, 2012, is when Venus is at its greatest western elongation (greatest angle away from the Sun as seen in the morning, or the highest it gets in the predawn sky).

* Sunday, December 2, 2012, is when Jupiter is in “opposition,” effectively opposite the Sun as seen from Earth, the equivalent of a “full” Jupiter when the planet is closest to the Earth and rises around sunset, is highest in the night sky at midnight, and sets around sunrise. This is a good time to get out a telescope or a good pair of binoculars and watch Jupiter’s four large moons as they move around in their orbits. One of the earliest reasonably accurate estimates of the speed of light came from observing these moons. Navigators needed accurate clocks to calculate longitude, and tried using predictions of the positions of the moons of Jupiter to reset their clocks. But they found their predictions did not match their observations until they put in a corrections for the the time it took for light to get from the Jupiter to the Earth as the distance changed throughout the year.

* Tuesday, December 4, 2012, is when Mercury is at its greatest western elongation (greatest angle away from the Sun as seen in the morning, or the highest it gets in the predawn sky). Look for Mercury in the east-southeast about an hour before sunrise (about 6:10 am EST in the Washington, DC area). Venus will be the bright planet, look for Mercury about 7 degrees to the lower left of Venus (about halfway between the horizon and Venus at about an hour before sunrise). Saturn will be about 9 degrees to the upper right of Venus, and the bright star Spica even higher to the upper right.

* Thursday, December 6, 2012, is when the waning Moon is in its last quarter.

* In the morning on Sunday, December 9, 2012, look towards the southeast to see the waning crescent Moon near the bright star Spica. In a line to the lower left will appear Saturn, Venus, and then Mercury.

* By Monday morning, December 10, 2012, the waning crescent Moon will have shifted to be about 5 degrees to the lower right of Saturn.

* By Tuesday morning, December 11, 2012, the waning crescent Moon will have shifted to be about 3 degrees to the right of Venus, with Mercury to the lower left.

* On Wednesday, December 12, 2012, Jupiter will appear nearest the bright star Aldebaran (less than 5 degrees, apart). They will appear close to each other for several weeks around this time.

* Thursday, December 13, 2012, is the new Moon.

* Early in the morning on Friday, December 14, 2012, is the peak of the Geminid meteor shower, generally one of the two big meteor showers of the year. The peak is expected to be between 1 and 3 am EST, but increased meteor activity should be visible after about 10 pm for several nights around the peak. Near the peak, if the sky is clear and you are far away from city lights, you are likely to see about 50 meteors per hour (possibly more, as there is some indication that the intensity of this shower has been increasing in the last few years). The Geminids get their name from Gemini, as they appear to radiate out from this constellation. With the new Moon the night before, there will be no interference from moonlight, so this is a good opportunity to view this meteor shower. The Geminids are relatively slow moving as they hit the Earth and appear to be one of only two annual meteor showers associated with asteroids rather than comets. The Geminids appear to be dust associated with the asteroid 3200 Phaethon, which has an eccentric 1.4 year-long orbit that takes it out as far as the main asteroid belt and much closer to the Sun than Mercury. The problem is that it is hard to explain where all the dust that causes these meteors has come from. This asteroid probably has shot out gas and dust when it was close to the Sun in past orbits and may be an object in between an asteroid and a comet.

* Wednesday night/Thursday morning, at 12:19 am on December 20, 2012, is the first quarter or waxing half Moon.

* Friday, December 21, 2012, at about 6:12 am EST, is the winter solstice. The solstice is considered the start of winter in the northern hemisphere. Many people call the winter solstice the “shortest day of the year.” Although it is the day with the shortest daylight of the year, in terms of the time from solar noon to solar noon, the days on and just after the northern hemisphere winter solstice are the longest days of the year. I can send you and explanation of this if you are interested (I wrote them up a few years ago and don’t want to repeat myself too much, as this would be pedantic, repetitive, redundant, repetitious, and overdoing things a bit). The winter solstice has the shortest period daylight of the year but has neither the latest sunrise nor the earliest sunset. For the Washington, DC area at least, the earliest sunsets occur in early December, and the latest sunrises occurred even earlier, just before the change from Eastern Daylight to Standard Time.

* Early on Saturday morning, December 22, 2012, is the expected peak of the Ursid meteor shower. Although the Ursids can sometimes produce as many as 100 meteors per hour, most years you can only see 5 to 10 meteors per hour. The Ursids get their name because they appear to radiate out from near the bowl of the Little Dipper (the constellation Ursa Minor, which translates as the Little Bear). Because these meteors appear to radiate from high in the northern sky, this is one of the few meteor showers where you don’t have to wait until after midnight to see them. The Ursids are made up of dust left by the comet 8P/Tuttle.

* Sunday morning, December 23, 2012, about a hour before sunrise (about 6:20 am EST in the Washington, DC area), if you scan the southeast horizon with binoculars you may be to see Venus, and about 6 degrees to the lower right of Venus the bright, reddish colored star Antares.

* Tuesday, December 25, 2012 (Christmas Day), the waxing gibbous Moon will appear within about 1 degree of the bright planet Jupiter.

* The full Moon after next is on Friday, December 28, 2012.