October Meteor Shower Prospects
I can’t tell you how discouraged I am when I’ve written about an upcoming astronomical event, only to have it spoiled by cloudy skies. The latest event to suffer this fate was the 2012 Perseids, scheduled to peak during the early morning hours of Sunday, August 12.
While some folks may take the “been there, done that” attitude when it comes to observing meteor showers, I for one never tire of sitting out under a clear and dark sky to watch shooting stars blaze across the heavens. I have the same passion for observing the magnificent Saturn and his rings, as well as for watching the Galilean moons perform their celestial dance around Jupiter.
The observing prospects for the 2012 Perseids were good. Almost perfect, except for a waning crescent Moon rising around 1:30 am in the northeastern sky. The low center causing our adverse weather was not moving off very quickly. We got skunked once again.
What made matters worse is that through a variety of sources I learned that locations elsewhere around the globe were experiencing about 90 Perseids per hour at peak under much better circumstances.
Well, the storm system finally cleared southern New England and Sunday afternoon turned out to be a good day. Still a little humid, but mostly clear. Though the Perseid peak had past, one can usually see about one-quarter of the peak rates the night after.
I ventured out onto my back porch at 3:10 am on that following Monday morning. The temperature had dropped to the mid-60s, and the humidity had diminished somewhat. To the east was brilliant Jupiter, not far from Aldebaran, the bright star in the Hyades asterism of Taurus. Also visible was the Pleiades star cluster. (Seeing the stars of Taurus reminds one that winter is not really that far away.) Cassiopeia and Perseus were to the northeast, and the Great Square of Pegasus was prominent high to the south. Almost at zenith I could easily make out the Andromeda galaxy with the naked-eye. I could also see the crescent Moon behind the trees.
I sat down on a porch chair and began to scan the sky. Immediately I saw a satellite moving from north to south. Then a faint Perseid. Then another satellite. In just over one hour of observing I saw a total of 14 Perseids. Four of them left brief one- to two-second dust trails. One Perseid, at least as bright as Jupiter, left a dust trail that lasted 17 seconds. That meteor made the whole experience worthwhile.
As the Moon rose higher into the sky, its light illuminated the remaining humidity in the air. The eastern sky became much brighter due to this light scattering, but I don’t believe it drastically affected my observing session. The Moon was still below my tree-line, so the trees blocked it from direct view. I could also see Venus through openings between branches. When I called it quits around 4:20 am, the beautiful crescent Moon had finally cleared the trees.
Though I did not experience 90 Perseids per hour, the 14 meteors I did observe helped to rekindle my passion for sharing the beauty of the universe with others.
And all I had to do was to keep my eyes to the skies. (And stay awake of course!)
Stargazers will have two opportunities to scan the skies for meteors during October. The first shooting star display is a minor one called the Draconids. These particles, which were stripped off short-period (6.6 year orbit) comet 21P/Giacobini-Zinner, will hit the Earth’s atmosphere at a mere 12.5 miles per second—fairly slow for a meteor shower. The Draconids will reach their peak rate of about ten or less yellowish meteors per hour on the night of October 7-8.
Because the radiant is at its highest point in the northern sky early in the evening on the 7th, you can observe these occasional meteors before midnight. The almost Last Quarter Moon (on the 8th) will somewhat brighten the sky when it rises just before midnight.
To locate Draco, face north and you’ll see Ursa Major (Big Bear) and the Big Dipper asterism. Draco stretches between Ursa Major and Polaris, the pole star, which is the end star in Ursa Minor (Little Bear), the Little Dipper asterism handle. Draco descends towards the northern horizon to the left of Polaris as the night progresses. It would be best to scan this entire region of sky for Draconids. By morning twilight, Draco’s head will be sitting due north about 20 degrees above the horizon.
Conditions will be extremely favorable for our second meteor shower of the month—the Orionids (need I say, weather permitting of course). This major shooting star display will peak on the night of October 20-21, with the best activity occurring between midnight and dawn. The particles we will see disintegrating in our atmosphere at around 41.6 miles per second are the remnants of Halley’s Comet. The shower gets its name because the meteors appear to radiate out of the sky just above Orion’s head and not far from his bright red super giant star Betelgeuse, which marks his right shoulder.
Orion can easily be found. At 3:30 am this giant of a constellation will be due south of your location and about halfway up above the horizon. A waxing crescent Moon will set around 10:36 pm on the 20th, so it will not brighten the sky whatsoever. With observing conditions about as good as it can get, an observer can expect to see 20 or so yellow and green meteors per hour at peak. The Orionids are also noted for producing fireballs that create persistent dust trains high in the atmosphere.
Let’s hope the weather will cooperate so we can all enjoy a good display of shooting stars.
Keep your eyes to the skies.
David A. Huestis