Tuesday, 8 October 2013

Legendary Draconid meteors best after sunset

Before nightfall on October 7 and 8, as you’re preparing to watch for meteors, look southwest to see the waning crescent moon between the planets Venus and Saturn.

The constellation Draco the Dragon will be spitting out meteors, also known as shooting stars. The Draconid shower is predicted to produce the greatest number of meteors on the night of October 7, but the next night might be good, too. Watch for them first thing at nightfall. Fortunately, the thin waxing crescent moon won’t interfere with this year’s Draconid meteor display. In fact, the moon and planets set in the southwestern sky around nightfall, serving as a wonderful prelude to tonight’s Draconid meteor show.

Unlike many major showers, the radiant for the Draconids is highest up at nightfall, so it’s best to watch for these meteors as soon as darkness falls, not in the wee hours before dawn. Spend an hour or more under a dark and open sky, lying down and with your feet pointing northward. Oftentimes, this hard-to-predict shower doesn’t offer much more than a handful of languid meteors per hour. But watch out if the Dragon awakes!

Once again, watch at nightfall and early evening because that’s when the radiant point for the Draconid shower is highest in the nighttime sky. We emphasize it, because most meteor showers are best after midnight … but not this one.

The Draconid meteor shower produced awesome meteor displays in 1933 and 1946, with thousands of meteors per hour seen in those years. Even two years ago – in October 2011 – people around the globe saw an elevated number of Draconid meteors, despite a bright moon that night. European observers saw over 600 meteors per hour in 2011.

As far as we know, nobody is calling for the Draconid meteor shower to burst into storm in 2013. But you never know for sure with the Draconids, so it’s worth watching out for on the moonless evenings of October 7 and 8. Just keep in mind that meteor showers are notorious for defying predictions, either surpassing or falling shy of expectation. The only way to know for sure is to try to watch the shower.

In 2013 – approximately two years after the comet’s 2011 perihelion (closest point to the sun) – there might be another meteor storm around the time of this shower’s peak. Or there might not be.

Perhaps Draconid meteor rates will go up this year. Or we might see only a handful of meteors per hour. Under normal conditions, when astronomers speak of a meteor shower peaking, it is similar to a weather forecaster saying, “The heaviest rain/snow is predicted for such-and-such hour.” In other words, the prediction might not be precise, since nature is always unpredictable to a degree. But, generally speaking, the rate of meteors falling will be higher during the peak of a meteor shower than on any other night.

For tips on viewing meteor showers read this EarthSky article.

For a taste of history related to this shower, go to the Astronomy Abstract Service from the Smithsonian and NASA and find a 1934 article called “The Meteors from Giacobini’s Comet” by C.C. Wylie. It is an account of the famed meteor storm of 1933.

Finally: The radiant is highest in the evening hours, so no need to wait until after midnight. Find a dark, country sky and as much open sky as possible. Lie down on a reclining chair and look upward, starting at nightfall. How many Draconid meteors can you count in the moon-free skies these next few evenings? No one expects a Draconid storm this year, but it’s fun to wait and see.

-EarthSky