As we discussed last week, the best meteor shower of the year, the Perseid shower, is coming up in mid-August. Meteors, also called shooting stars, are streaks of light that appear in the sky for a second or so as bits of space debris burn up in Earth’s atmosphere.
During a meteor shower, Earth is passing through the detritus left by a passing comet. Thus, on meteor shower nights, the number of streaks increases dramatically from a few every hour to dozens during the peak hour of the shower.
This year, astronomical conditions conspire to make the Perseids not just the best of the year but perhaps the best meteor shower since the Leonids at the turn of the millennium.
The best time to observe the Perseid meteor shower this year is during the early (and I do mean early) morning of Friday, Aug. 12, from just after midnight until the rising sun spoils the view. This year, we may see as many as 150 meteors during the last hour of complete darkness from 3:05 to 4:05 a.m.
During my many forays to dark skies to see the Perseids, I have watched many people drive up to an observing site, stare fitfully at the sky for an hour or so, pronounce the display a dud, and drive home. Those who stick with the experience to its glorious end are often rewarded with the experience of a lifetime.
In fact, you can maximize the number of streaks you see by following a few simple guidelines:
1. Go to dark, rural skies away from city lights. Don’t come, for example (I beg you), to Perkins Observatory. We’ll be in Middle-of-Nowhere, Ohio, seeing a spectacular display, not fighting the sky glow at Perkins.
2. Sit in a lawn chair and stare in the direction least polluted by any city lights on the horizon.
The meteors will seem to originate from the constellation Perseus, which appears on the horizon at about 10 p.m. local time. However, the most meteors will be visible after midnight. They can appear all over the sky, but they will always look like they’re streaking away from Perseus.
Meteors will occur all over the sky. Straight up is always good if you have a chaise lounge and the innate ability to stay awake horizontally.
3. Use your peripheral vision to see as much of the sky as possible.
4. Listen to me now. This is important. Stick it out until morning twilight. You’ll see a LOT more meteors during predawn hours on Friday than you will just after dark Thursday night.
Here’s why: Earth is traveling at 30,000 miles per hour around the sun. Before local midnight, you are facing away from the direction of Earth’s motion. Consequently, the specks of space crud have to play catch-up with Earth to hit it. After local midnight, you are facing in the direction of Earth’s orbital motion. Earth is doing most of the work by slamming into the space debris.
I call this principle the “Bug on the Windshield Effect.” On a meteor-shower night, Earth is much like your car traveling through a swarm of bugs. You won’t see many bugs on the back windshield. Wait for Earth to turn into the direction of the swarm.
Also, the moon — that bright, meteor-obscuring streetlight in the sky — doesn’t set until after midnight.
As a result, between 10 p.m. and local midnight, which is, because of the vicissitudes of daylight saving time and our position in the time zone, about 1:30 a.m., you may see very few meteors. Between 3 and 5 a.m., you may see as many as 150 per hour.
The best display almost always happens in the last hour before morning twilight spoils the view.
5. Take along a blanket and some bug repellent. It gets chilly at night, and you don’t want the mosquitoes to think of you as a cold luncheon buffet.
6. If skies are cloudy, you won’t see any meteors. If the forecast looks bad for Friday morning, try Thursday morning. If it’s cloudy both mornings, try Saturday morning if it’s clear then. The shower will be much diminished Thursday and Saturday mornings, but it beats seeing nothing at all.
7. Try to get some sleep before you drive back. The life you save may be mine. I’ll be driving back, too, you know.
8. Prepare a good excuse for your boss in advance. You don’t want her or him to think you’re an oddball. (“No, er, I wasn’t STARGAZING. I was, uh, drinking heavily all night. Yeah. That’s it.”) Lack of sleep and 300 meteors have a way of making you look a tad starry-eyed as you float from cosmic splendor back to so-called reality.
Tom Burns is director of the Perkins Observatory in Delaware.