ANTICIPATION BUILDS FOR TONIGHT’S METEOR SHOWER: This weekend, Earth will pass through a stream of debris from Comet 209P/LINEAR. If forecasters are correct, the encounter could produce an outburst of bright meteors numbering more than 200 per hour. Most models agree that peak rates should occur between the hours of 0600 UT and 0800 UT (2 a.m. and 4 a.m. EDT) on Saturday morning, May 24th, a time frame that favors observers in North America. It is worth noting, however, that Earth has never encountered this stream of debris before, so forecasters cannot be certain of their predictions. The display could be a complete dud, a fantastic “meteor storm,” or anything in between. Whatever happens, NASA plans to chat about it.
It is often said that this is a new shower, and no one has ever seen a Camelopardalid meteor before. Well…maybe just one. “We searched through our database of several thousand bright meteors and found a likely candidate,” reports Bill Cooke of NASA’s Meteoroid Environment Office. “Back on May 9th of 2012, one of our all-sky cameras caught it burning up at an altitude of 66 kilometers.” This is what it looked like:
“Peaking at a magnitude of -2 (Mars brightness), our now-extinct visitor was about 3.3 cm in diameter – a little smaller than a ping pong ball,” continues Cooke. “We believe it was a May Camelopardalid because it had an orbit that greatly resembles that of parent Comet 209P/LINEAR.” The diagram, below, shows the match:
“So why is this good?” asks Cooke. “Looking back to 2012, our computer models show very little comet debris near Earth. We predicted nothing, yet got one meteor. Does this mean that a legion of his siblings will show up this year, when the models suggest the potential of a full-fledged meteor outburst? I’m getting excited about Friday night/Saturday morning.”
Earth won’t be the only body passing through the debris zone. The Moon will be, too. Meteoroids hitting the lunar surface could produce explosions visible through backyard telescopes on Earth. The inset in this picture of an actual lunar meteor shows the region of the crescent Moon on May 24th that could be pelted by May Camelopardalids:
According to NASA’s Meteoroid Environment Office, the best time for amateur astronomers to scan the Moon for lunar meteors is after 0800 UT (4 a.m. EDT) on May 24th.
There is much uncertainty about the strength of this shower, both on Earth and on the Moon. As far as we know, our planet has never passed directly through a debris stream from Comet 209P/LINEAR, so no one knows exactly how much comet dust lies ahead. A magnificent meteor shower could erupt, with streaks of light in terrestrial skies and sparkling explosions on the Moon–or it could be a complete dud
from: spaceweather.com
And when we say August 12 or 13, we mean the morning hours after midnight – not that night. Unfortunately, the full moon will spoil 2011′s Perseid display, obscuring all but the brighter meteors, during the shower’s actual peak. But you will see Perseids in the weeks leading up to the peak, too, if you have dark skies. These typically fast and bright meteors radiate from a point in the constellation Perseus the Hero. You don’t need to know Perseus to watch the shower because the meteors appear in all parts of the sky. The Perseids are considered by many people to be the year’s best shower, and often peak at 50 or more meteors per hour – in years when the moon is out of the sky. However, 2011 is not a great year for the Perseids, because the moon is full on the expected peak date. The Perseids tend to strengthen in number as late night deepens into midnight, and typically produce the most meteors in the wee hours before dawn. These meteors are often bright and frequently leave persistent trains. Start watching for the Perseids in the first week of August. They will be building gradually to their peak. By the second week of August, the moon will begin interfering with the skies between midnight and dawn. On the mornings of August 12 and 13, you can still watch for some Perseid meteors to streak across this short summer night from midnight until dawn. Yet the full moon will interfere.