- What? Like all meteor showers, the Perseids occur annually. Also like all meteor showers, the Perseids are caused by the Earth making its way through the debris field of a comet that passed years prior. Those little specks of dust and rock (about 1 to 10mm in size) that the comet left behind smack into the Earth's atmosphere at about 35 miles per second and burn up in an instant, emitting a bright streak of light in the process. Different meteor showers are attributed to different comets. The comet in question for the Perseids is Comet Swift-Tuttle (109P/Swift-Tuttle), which made its way through the inner solar system most recently in 1992.
- How? Get away from city lights! That's the most important bit of advice for viewing a meteor shower (other than open your eyes and look up). City lights create light pollution and wash out the fainter stars and meteors of the night sky. Go to the desert or the mountains at least 90 minutes from LA. Sit back in a comfortable reclining chair or lay on the ground with a blanket and/or air mattress. Aim yourself so you're looking northeast, but look up. Meteor showers are named for the constellation from which they appear to radiate. The Perseids are named for Perseus, which rises in the north east. But that doesn't mean you'll only see meteors in the vicinity of Perseus. They can appear anywhere in the sky, but they will always appear to radiate from Perseus, an effect of linear perspective. You don't need (or want) a telescope or binoculars to view a meteor shower, just your dark-adapted eyes.
- When? Thursday night (8/11) into Friday morning (8/12). It'll actually be early Friday morning, about 1:00AM, by the time best viewing begins.
|A Perseid meteor from the 2012 display shoots through the field of view in this image of the Heart Nebula.|
100-minute exposure using a Takahashi FSQ-106EDX telescope and FLI ML11002-C camera.
- What constitutes "best viewing"? Perseids appear to emanate from Perseus. Perseus rises relatively late in the evening this time of year and climbs higher throughout the early morning hours. The higher in the sky the radiant is, the clearer view we'll have of the meteors. Also, for the sky to be at its darkest, there must be no Moon. During this year's Perseid peak, the Moon sets at about 1:00AM (PDT) on Friday morning. When those two conditions are met (Perseus is high in the sky and the Moon has set), prime viewing will begin. This occurs between 1:00AM and dawn on Friday, 8/12. That's not to say you won't see any meteors on Thursday evening. You will. But you'll likely see more after midnight and after the Moon sets.
- Will the sky be full of meteors? While the event is indeed called a "meteor shower," keep in mind that any source that claims there will be a "shower of meteors raining down" or something similar, is full of it. They probably also have photos of sharks attacking helicopters and warn of impending doom by a previously undiscovered sister star of the Sun. Except for very rare occasions, meteor showers typically consist of 1 or 2 streaks per minute, and that's considered a really good display! The Leonid meteor shower is known to have periodic "outbursts" — the 1966 and 1998 Leonids were considered meteor storms!
- But I heard this year's Perseids are going to be crazy active. Is that true? This year's Perseids are predicted (by some) to be more active than most years — The theory is that Jupiter has perturbed the debris field left by Comet Swift-Tuttle, and placed a denser portion of it in Earth's orbital path. The problem is that no one knows for sure the density of the debris field, how squarely the Earth will hit it, what part of the Earth will hit it and when exactly, etc. The predictions rely on models that use a lot of assumed data. Remember Comet ISON? Yeah.
Get more information about the source of the Perseid meteors, Comet Swift-Tuttle. And find out more about meteor showers.
Enjoy the "shower!"