A nearly moonless sky means conditions are nearly perfect for the Leonids, an annual meteor shower whose reputation outshines reality.
The Leonids peak Monday night and Tuesday morning, with the best viewing generally coming between midnight and dawn. That's when our planet is turning directly into the trail of cosmic grit left behind by Comet Tempel-Tuttle, which last passed through the inner solar system in 1998.
The show can be spectacular when Earth passes through a relatively thick stream of debris, as it did in 1833 as well as the 1999-2002 time frame. During such meteor storms, observers could see thousands of shooting stars per hour.
This isn't one of those years.
“We’re predicting 10 to 15 meteors per hour,” Bill Cooke of the Meteoroid Environment Office at NASA's Marshall Space Flight Center said in an online preview.
That pales in comparison with August's Perseids (40 or more per hour) or December's Geminids (50 or more per hour). Nevertheless, the Leonids are worth a look — and even if the skies are cloudy in your locale, you can catch the show online.
Here's a top-ten roundup of tips and resources:
- Viewing conditions are better than usual this year because the moon is in its waning crescent phase, which means you won't have to fight the moonlight's glare. The slender moon rises after 2 a.m. local time.
- Meteors flash when bits of cometary grit zoom through the upper atmosphere and create bright ionized trails. But it's easy to miss seeing those flashes in light-polluted urban skies. To see more meteors, get as far away as you can from city lights. The higher the elevation, the better.
- The Leonids appear to emanate from a point in the constellation Leo, but they can be anywhere in the sky. Try to find a viewing spot that's not blocked by trees, buildings or other obstacles. Look straight up from a lounge chair or a blanket, and take in as much of the sky as you can with your eyes. You don't need to use a telescope or binoculars.
- November can get pretty chilly, so dress warmly. It's not a bad idea to bring snacks and a hot drink to keep up your energy.
- If you don't already have a favorite meteor-watching spot, the Clear Sky Chart can show you locales that are expected to have good viewing conditions. You can also check with your local astronomy club.
- NASA's Fluxtimator applet provides predictions of the expected meteor rate, based on your locale as well as sky conditions and time of night. Make sure that your Java software and security settings are up to date, and that you enter the correct parameters into the applet.
- NASA is providing a Ustream video feed of the sky view from a telescope at Marshall Space Flight Center in Huntsville, Alabama, from 7:30 p.m. ET to sunrise Tuesday. Check this webpage for information on the video feed, and this page for more about the Leonids from NASA.
- The Slooh virtual observatory is also planning a webcast about the Leonids, starting at 8 p.m. ET. Views will be provided from telescopes in the Canary Islands and Arizona, and you can hear the audio buzz created by meteor ionizations. For an alternate soundtrack, tune in online to SpaceWeather Radio. Here's a sound sample.
- After the Leonids peak, look for images of shooting stars on SpaceWeather.com. If you snap a great meteor photo, why not share it? Let us know by using the hashtag #NBCmeteor on Twitter or Instagram, and we'll pass along our favorites.
- Even if the Leonids are a total washout, we'll still have the Geminids to look forward to. Think of your outing as a test run for the Geminids' peak night of Dec. 13-14.