It's getting to be our favorite time of the year up here in the Northwest. August means warmer nights and one of our favorite meteor showers—the Perseids!
With enough patience under a remote, moonless sky, even the most novice observer is bound to catch a glimpse of a wayward meteor. Often little more than fleeting slivers of light—or dazzlingly bright by fortunate chance—meteors are small specks of cosmic debris (typically smaller than a grain of sand) colliding with Earth's atmosphere at tremendous speed and burning up upon entry.
The misnomer 'shooting star' is a popular term for meteors, carried over from a time when the nature of these cosmic charms was still unknown. It is now known, however, that meteoroids (the term for a meteor prior to entering Earth's atmosphere) are mostly cometary in origin. Therefore, when Earth crosses the former path of a comet, it passes through a field of leftover debris and a meteor shower occurs. Whatever direction the Earth happens to be travelling at the time of interception generally gives the shower its respective name.
So how does one best view this year's Perseids? There are a few important tips to keep in mind if you are planning to watch:
1. Timing. The peak date for the 2016 Perseids will be August 11-12 but in reality you don't need to view them on the exact peak date to enjoy them. You could try tonight, in fact, and you'd be sure to catch a few! If you're not interested in early morning viewing, these next few evenings are a better time to get out there because the Moon is still a crescent (read on for why this matters).
2. Darkness. Meteors can be bright but most of the time they are relatively faint so you'll want to find the darkest sky possible. Not only does that mean getting far away from city lights but also checking if the Moon is likely to spoil your darkness. We have a first quarter Moon to contend with this year, so early morning observing will be better than the evening hours (you'll have to wait until around 1:00AM for the Moon to set on August 11).
3. Where to look. Many people are under the false impression that you must know exactly where to look to watch a meteor shower. While it is true that meteor showers do originate from a point in the sky (the Perseids radiate from Perseus), as long as this radiant is above the horizon it is best to relax your gaze and let your eyes wander. Meteors will be seen streaking across many parts of the sky. But if you're looking for the sweet spot, use Sky Guide to point you in the right direction.
4. Patience. Meteor showers vary in both strength and rate so don't be disappointed if you don't see one right away. When it comes to meteor showers, those who wait are sure to be rewarded!