¡SkyCaramba! Weekly astronomy blog for the week ending December 21, 2013
Northern hemisphere sky watchers have a chance to see meteors from three separate showers during the next three weeks or so.
The Geminids were expected to peak on December 13th and 14th. You may still see a few of them as this article comes online. The Geminid shower comes from an asteroid named 3200 Phaethon. It’s thought to be an old comet that has lost all or nearly all of its dusty head. Earth still passes through dust trails it left behind and 3200 Phaethon appears to still have some dusty material coming off of it.
The Geminids get their name from Gemini, the constellation they seem to radiate from as Earth’s atmosphere sweeps up the tiny rocks in the dust trail. You may see up to 120 colorful meteors per hour from this shower.
The Ursids radiate from Ursa Minor, or if you prefer, the Little Dipper. This year’s peak is forecast to be on December 22nd at 3 hours Universal Time. This one’s not actually a very well known shower. It has produced outbursts just a few times in the last century. But one astronomer feels Earth could pass through another dust trail responsible for it this year.
The Ursids’ parent comet is 8P/Tuttle, which was at perihelion in 2008. Those close approaches to the sun cause more dusty material to come off. The sooner after a comet’s perihelion that Earth passes through such a dust trail, the more likely the trail will produce a shower. On average, the Ursids produce just 12 meteors per hour. But you can hope for a good year.
Moonlight will be a problem for the Geminid and Ursid showers in December. However, perhaps up to 80 meteors per hour will be seen from the Quadrantids meteor shower. It’s expected to peak around January 3rd. The new moon won’t interfere.
The Quadrantids are also associated with an asteroid, 2003 EH1. Not only has it lost its dusty sheath, what’s left of the rock at the center may be breaking up. At one of the links below, you can see a video of a Quadrantid meteor trail dispersing in the atmosphere.
The Quadrantid shower is named for Quadrans Muralis, a constellation no longer included on modern star charts. It was located between Boötes and Draco.
Dress warm while you’re looking for meteors. Take out a lawn chair to recline on to make the task easier on your neck. And when you see one, try to trace it back to the constellation it came from. Here are some simulated views to help you.
¡SkyCaramba!
http://www.spacedaily.com/reports/Rock_Comet_Sprouts_a_Tail_999.html
http://www.spaceweather.com/archive.php?view=1&day=06&month=01&year=2011