Astronomy: Orionid Meteor Shower Peaks October 20-21

The Orionid meteor shower peaks late tonight/early tomorrow, through Tuesday night/Wednesday morning.  As an erstwhile amateur astronomer, the Orionids have always interested me, despite the fact that they can me somewhat faint, because the dust and particles that burn up through our atmosphere for this shower come from comet 1P/Halley, better known as Halley's Comet, she of the 76 year orbit and next appearance in 2061.  Halley's Comet was the first comet to have its orbit understood, and its periodic nature verified, so on top of the fact that it can offer some phenomenal performances (alas, not in 1985/86), it's got great scientific value.

According to Space.com:

Although meteors can look bright in the night sky, they result from very small fragments of comets and other debris. A typical meteor fragment is the size of a dust grain, or perhaps a tiny pebble. In the case of the Orionids, these fragments came from Halley's Comet as it approached the sun. The heat of the sun melts the conglomeration of ices on comets as they approach, leaving a trail of dust and debris in the comet's wake.

The meteor shower results when our planet plows into the dust trail left behind by Halley. From Earth's perspective, the comet fragments appear to come approximately from the direction of Betelgeuse, a bright red supergiant star in Orion. However, NASA says, staring at the direction of Orion will make you miss a lot of meteors. 

"They are visible throughout the night sky," the agency wrote. "It is actually better to view the Orionids at least 90 degrees away from the radiant. They will appear longer and more spectacular from this perspective. If you do look directly at the radiant, you will find that the meteors will be short — this is called foreshortening."

Their suggestion holds true for most meteor showers.  it is typically best, if you are observing, to turn your view at least 90 degrees away from the radiant (where the meteors appear to come from...in the case of the Orionids, they seem to come from the bright red star at Orion's shoulder, named Betelgeuse, Beta Orionis)...it gives you the best chance to see more meteors, and with longer trails (see map right below to see where the radiant is).

The ZHR (Zenith Hourly Rate...that is, the maximum rate on a clear moonless night if the meteors were coming from directly overhead, or the zenith) averages 20 to 25 meteors per hour, but some years there can be as many as 50 to 70 and hour over short bursts.  The meteors average magnitude 3.0 brightness...roughly equivalent to the stars visible from a city neighbourhood without binoculars or a telescope.  So you'll want to get out in the country, to a nice dark sky site, to take advantage of this one.

If you do, drop me a comment and tell me how it went!