The Perseid meteor shower, a celestial event eagerly awaited by millions of skywatchers around the world, is about to make its annual return to the night sky. The shower is predicted to reach its peak the morning of Monday, August 12th, but viewers should plan to start looking for meteors at nightfall on Sunday, August 11th. In a dark site away from light pollution, at the peak of the shower, observers might see one meteor per minute!

Light from the Moon, which will be just shy of first quarter, will somewhat affect viewing before midnight. "But as the Moon sets before midnight local time, the rest of the night is primed for perfect viewing circumstances," says Diana Hannikainen, Sky and Telescope's Observing Editor.

Begin watching for meteors soon after evening twilight ends on the evening of August 11th. By then the shower's radiant - its perspective point of origin in the constellation Perseus - has risen above the northeastern horizon. The few Perseids that appear this early will be spectacularly long "earthgrazers" that skim along the top of the atmosphere. The higher the radiant, the more meteors you'll see - so when Perseus climbs higher in the northeast, especially after midnight, more meteors should appear all over the sky.

Given the timing of the peak, you'll have a second chance for observing on the evening of Monday, August 12th, and into the early morning of August 13th. In fact, the Perseids are a long-lived event, and you should see meteors - though fewer in number - for several nights before and after its predicted peak.

How To Watch
To enjoy the Perseids, you need no equipment but your eyes - binoculars and telescopes show too small an area of sky to be useful for meteor-watching. Find a dark spot away from bright lights with a wide-open view all around if possible.

You'll want to make yourself comfortable to fully enjoy the show - craning your neck for many hours can ruin your experience. Bring a reclining lawn chair or picnic blanket so you can lie back. Bundle up in blankets or a sleeping bag, both for mosquito shielding and for warmth; clear nights can grow surprisingly chilly, even in August.

Once you're comfortable, be patient and let your eyes adapt to the darkness. Give yourself at least 20 minutes before expecting to see multitudes of meteors. "And do resist looking at your phone during this time - or at any time during the night - because the harsh, bright light from the screen will wash away whatever dark adaptation you've built up," says Hannikainen.

"Shooting stars" can appear anywhere and everywhere in the sky, so you don't have to look toward the radiant to see them. The best direction to watch is wherever your sky is darkest, usually straight up. Faint Perseids appear as tiny, quick streaks. Occasional brighter ones might sail across the sky for several seconds and leave a brief train of glowing smoke.

When you see a meteor, trace its path back to its origin. If you eventually come to the constellation Perseus (see the accompanying sky chart), you've just witnessed a Perseid. Occasionally, you might spot an interloper. The weaker Delta Aquariid, Alpha Capricornid, and Kappa Cygnid showers are also active during Perseid season, and there are always a few random meteors too. All of these come from other parts of the sky. It's a fun exercise to trace meteors back to their radiants: If the tracks don't lead you to Perseus, they aren't Perseids!

"The main thing that would hamper enjoyment of the spectacle would be clouds or light pollution," Hannikainen cautions. Only the brightest meteors shine through light pollution (though usually not through clouds). But there's good news for those in light-polluted areas: A NASA analysis of all-sky images taken from 2008 to 2013 shows that the Perseids deliver more bright meteors (those that outshine any star) than any other annual meteor shower.

How And Why
Meteors are caused by tiny, sandgrain- to pea-size bits of dusty debris striking the top of Earth's atmosphere that burn up more than 50 miles (80 km) above the ground. The average Perseid zips in at 37 miles per second, glowing as it burns to soot and creating a quick, white-hot streak of superheated air. The nuggets in Grape Nuts cereal are a close match to the estimated size, color, and texture of typical meteor-shower particles.

The Perseid bits were shed long ago by Comet Swift-Tuttle and are distributed all along the comet's orbital path around the Sun. Earth passes through this tenuous "river of rubble" every year in mid-August. The comet is so named because it was independently discovered by Lewis Swift and Horace Parnell Tuttle in July 1862.

Mars And Jupiter Meet In The Morning
The celestial spectacle doesn't stop with the Perseids. In the early morning hours of Wednesday, August 14th, Jupiter and Mars will be really close on the sky - less than 0.5 apart. How close is that? Well, if you stretch your hand out to arm's length, the apparent distance between the two planets would span less than half the width of your little finger. That's close, and well worth staying up late or getting up early to see. (We should note, though, that even though the two will appear right next to each other on the sky, they'll actually still be separated by more than 300 million miles, or 500 million km.)

The planets will still be very close in the mornings preceding and those following August 14th, so if you're clouded out on the date of closest conjunction, it's well worth the effort to catch this sight on one of the other mornings. The two planets will look slightly farther apart - a little more than twice the distance - on the morning of the peak of the Perseids. What better way to crown a night of meteor-watching than with the delightful sight of the conjunction of brilliant Jupiter and ruddy Mars!

To take in this view, face east-northeast - that's approximately in the direction where the Sun rises at this time of year at mid-northern latitudes. No equipment is required to enjoy this sight - in fact the unaided-eye view is the most pleasing, as the planetary duo nestles between the horns of Taurus, the celestial Bull, with the Pleiades star cluster not far to the upper right and orangey Aldebaran to their right. If you have a pair of binoculars lying around, pointing them at Jupiter will reveal the planet's four largest moons.

No matter what sight you take in, between the Perseids and the planets there'll be plenty to enjoy!

Related Links
Perseids at Sky and Telescope
Asteroid and Comet Mission News, Science and Technology