meteor shower

Would you like to see a piece of the Halley's Comet? Go outside on Sunday morning, 21 October, around 1 AM, and start looking east (no telescope required). Every 10 minutes or so you'll see a meteor streak. It is not an intense shower, about 20 to 30 meteors per hour. The meteors can be seen anywhere in the sky, but they appear to stream out of a point, called 'the radiant,' in the constellation Orion.

Don't stare at that spot, meteors near the radiant seem short and stubby, a result of foreshortening. Instead, look toward any dark region of the sky about 90 degrees away. You'll see just as many Orionids there, but they will seem longer and more dramatic.

Although the Orionids are not so spectacular as the Perseids, which peak around 12 August, they are consistent. The Orionids are related to the eta Aquarids, a southern hemisphere meteor shower in May. Both spring from Halley's Comet. Earth comes close to the orbit of Halley's Comet twice a year, once in May and again in October and although the comet itself is rarely nearby, Halley's dusty debris constantly moves through the inner Solar System and causes two regular meteor showers. Orionid meteoroids are very fast. They strike Earth's atmosphere travelling 66 km/s.

Sky gazers could be in for a show Sunday night as the annual Orion meteor shower passes the Earth.



Named for the constellation Orion, the shower is the result of debris left over from Haley's Comet, which last passed the planet in 1986.



"Last year was a good bright year for it," said North Country Weather meteorologist Craig Bourquin. "This year is expected to be a pretty good meteor shower as well."

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The best time to see the shower is after 11 p.m. toward the east, Bourquin said.



He added, however, that skies may be partly cloudly and could partially obscure the view.



And of course, it's best to find a dark place.

"Basically any place where there's the least amount of artificial light possible," Bourquin said. "This is where people out on farm lands have it nice."
The annual Orionid meteor shower peaks early Sunday morning and could put on a delightful display for skywatchers with clear, dark skies.

The Orionids are created by tiny bits of debris thought to be left in space by Halley's Comet as it orbits the sun. Each year, Earth passes through the debris trail, and the material lights up as it vaporizes in our atmosphere, creating "shooting stars."

In the countryside away from light pollution, the Orionids typically serve up around 20 meteors per hour during the peak. This year could be double that, said Joe Rao, SPACE.com's Skywatching Columnist. The estimate is based on a tentative new prediction from Mikaya Sato and Jun-ichi Watanabe of Japan's National Astronomical Observatory. However, meteor shower predictions are notoriously difficult, experts agree.

Either way, cloudless skies and dark conditions away from streetlights and house lights would make for an enjoyable show anytime between 1:30 a.m. and daybreak Sunday, Rao figures.

"Almost certainly, you should sight at least a few of these offspring of Halley's Comet as they streak across the sky," he said.

Urban skywatchers would see far fewer meteors.

The meteors can appear anywhere in the sky, but will all seem to emanate from a single point, called the radiant. The radiant for the Orionids, in the constellation Orion, will be high in the southern sky in the predawn hours.

Meteor watching is best done from a location with a broad view of the sky. A blanket or lounge chair allows the skywatcher to comfortably lie back and look up. Seasoned observers advise wearing much warmer clothing than you think you might need. Telescopes and binoculars are not needed.

The Orionid shower is already under way and ramping up, producing a handful of meteors each hour after midnight. So, the mornings immediately surrounding the peak could be worth a look too, Rao said.

Editor's Note: SPACE.com will provide a complete viewer's guide to the Orionids Friday Halley's comet will produce a magnificent meteor shower this week, though the celestial body itself won't return to Earth's skies for more than 50 years.

The annual Orionid meteor shower, which peaks this weekend, is spawned by fragments of the universe's most famous comet.




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At its peak, this weekend's shower may produce up to 15 or 20 meteors an hour that can be seen by the naked eye.

Although the Orionids are not the most spectacular of sky shows, meteor enthusiasts look forward to the cosmic event for its consistency in timing and intensity.

"They are pretty much an Old Faithful type of reliable shower," said Alan MacRobert, a senior editor at Sky and Telescope magazine.

And this year the moon is being especially cooperative, setting during the wee hours to produce darkened skies and the potential for more meteor sightings.

"We have a window of moonless sky, so this is one for which regular meteor observers are going to be out," MacRobert said.

The shower should peak during the early morning hours of October 21 but will be visible from October 20 to 24.

The who are curious to see the show might want to brew some coffee. The Orionids are best spotted in the hours between moonset―typically well after midnight―and the start of dawn some 90 minutes before sunrise.

Echoes of Halley's

The Orionids are the result of Halley's comet shedding a layer of dust particles as i
What are meteor showers?

An increase in the number of meteors at a particular time of year is called a meteor shower.

Comets shed the debris that becomes most meteor showers. As comets orbit the Sun, they shed an icy, dusty debris stream along the comet's orbit. If Earth travels through this stream, we will see a meteor shower. Depending on where Earth and the stream meet, meteors appear to fall from a particular place in the sky, maybe within the neighborhood of a constellation.

Meteor showers are named by the constellation from which meteors appear to fall, a spot in the sky astronomers call the radiant. For instance, the radiant for the Leonid meteor shower is located in the constellation Leo. The Perseid meteor shower is so named because meteors appear to fall from a point in the constellation Perseus.

What are shooting stars?

"Shooting stars" and "falling stars" are both names that people have used for many hundreds of years to describe meteors -- intense streaks of light across the night sky caused by small bits of interplanetary rock and debris called meteoroids crashing and burning high in Earth's upper atmosphere. Traveling at thousands of miles an hour, meteoroids quickly ignite in searing friction of the atmosphere, 30 to 80 miles above the ground. Almost all are destroyed in this process; the rare few that survive and hit the ground are known as meteorites.

When a meteor appears, it seems to "shoot" quickly across the sky, and its small size and intense brightness might make you think it is a star. If you're lucky enough to spot a meteorite (a meteor that makes it all the way to the ground), and see where it hits, it's easy to think you just saw a star "fall."

How can I best view a meteor shower?

If you live near a brightly lit city, drive away from the glow of city lights and toward the constellation from which the meteors will appear to radiate.

For example, drive north to view the Leonids. Driving south may lead you to darker skies, but the glow will dominate the northern horizon, where Leo rises. Perseid meteors will appear to "rain" into the atmosphere from the constellation Perseus, which rises in the northeast around 11 p.m. in mid-August.

After you've escaped the city glow, find a dark, secluded spot where oncoming car headlights will not periodically ruin your sensitive night vision. Look for state or city parks or other safe, dark sites.

Once you have settled at your observing spot, lay back or position yourself so the horizon appears at the edge of your peripheral vision, with the stars and sky filling your field of view. Meteors will instantly grab your attention as they streak by.

How do I know the sky is dark enough to see meteors?

If you can see each star of the Little Dipper, your eyes have "dark adapted," and your chosen site is probably dark enough. Under these conditions, you will see plenty of meteors.

What should I pack for meteor watching?

Treat meteor watching like you would the 4th of July fireworks. Pack comfortable chairs, bug spray, food and drinks, blankets, plus a red-filtered flashlight for reading maps and charts without ruining your night vision. Binoculars are not necessary. Your eyes will do just fine.
The annual Perseid meteor shower is expected to put on a great show this year, peaking in mid-August with a display of dozens of shooting stars each hour.

The Moon will be out of the way, leaving dark skies for good viewing as Earth plunges through an ancient stream of comet debris. Little bits, most no larger than sand grains, will vaporize in Earth's atmosphere, creating sometimes-dramatic "shooting stars."

"It's going to be a great show," said Bill Cooke of NASA's Meteoroid Environment Office at the Marshall Space Flight Center in Alabama. "The Moon is new on August 12, which means no moonlight, dark skies and plenty of meteors."

How many?

This year the Perseid meteor shower could deliver one or two visible streaks every minute during peak times, Cooke said in a statement yesterday. Urban skywatchers will see fewer due to local light pollution.

The meteors in this shower all appear to emanate from the constellation Perseus. The best times to watch will be late night Aug. 12 through dawn Aug. 13.

"The August Perseids are among the strongest of the readily observed annual meteor showers, and at maximum activity nominally yield 90 or 100 meteors per hour," said Joe Rao, SPACE.com's Skywatching columnist. "However, observers with exceptional skies often record even larger numbers."

Observing tips

To see the show, one need only find a comfortable spot with a clear view of the northeast horizon, away from local lights. A dark rural location is best. Lie back on a blanket or lounge chair and scan the entire sky. In the late evening, starting around 9 p.m. local time, sharp-eyed observers might see "earthgrazing" meteors that skim the northeast horizon.

"Earthgrazers are long, slow and colorful," Cooke said. "They are among the most beautiful of meteors." But don't expect more than a handful in an hour, he said.

Later and during the overnight hours, the shooting stars will be higher in the sky as Perseus rises. Some skywatchers enjoy counting the number of meteors they see per minute, per hour or during a 15-minute interval and comparing notes.

Telescopes and binoculars are no help, as the meteors move too swiftly and are best observed with the naked eye.

The cosmic rivers of debris have been laid down for millennia by the comet Swift-Tuttle, which passes through the inner solar system every 130 years. Perseid meteoroids are exceptionally fast, entering Earth's atmosphere at roughly 133,200 mph (60 kilometers per second) relative to the planet, slamming into the air like bugs hitting a windshield.