We heard from many friends on Facebook that the 2012 Orionid meteor shower – which peaked on Sunday morning, October 21 – was great fun. Many saw meteors, or shooting stars,
streaking along in dark skies. Will you still see meteors after the
shower’s peak? Maybe. Meteor showers in annual showers, like the
Orionids, happen when debris from comets enters our atmosphere and
vaporizes. It takes Earth several weeks to ford a meteor stream in
space. We started hearing reports of meteors in dark skies about a week
before the shower’s peak. It makes sense that you might see meteors –
albeit far fewer than at the peak – for a week or so after October 21.
The Orionids meteors originated in Comet Halley – the most famous of
all comets. It last visited Earth in 1986. As the comet moved through
near-Earth space, it left behind debris in its wake – bits of ice, dust
and rubble – that strike Earth’s atmosphere most fully around October
20-22.
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The
Orionids radiate from a point near the upraised Club of the
constellation Orion the Hunter. The bright star near the radiant point
is Betelgeuse.
The waxing crescent moon sets before midnight on October 20, and that means a dark sky between midnight and dawn, or during the best viewing hours for the 2012 Orionid meteors. On a dark, moonless night, the Orionids exhibit a maximum of about 25 meteors per hour. These fast-moving meteors occasionally leave persistent trains and bright fireballs. If you trace these meteors backward, they seem to come from the Club of the famous constellation Orion the Hunter. You might know Orion’s bright, ruddy star Betelgeuse. The radiant is north of Betelgeuse. The Orionids have a broad and irregular peak that isn’t easy to predict. More meteors tend to fly after midnight, and the Orionids are typically at their best in the wee hours before dawn. The best viewing for the Orionids in 2012 will probably be before dawn on October 21. Try the days before and after that, too, sticking to the midnight-to-dawn hours..
November 4/5, 2012, late night November 4 until dawn November 5 South Taurids
The South (and North) Taurids are perhaps best suited to die-hard meteor aficionados. The meteoroid stream that feeds the Taurids is very spread out and dissipated. That means the Taurids are extremely long lasting (September 25 to November 25) but usually don’t offer more than about 7 meteors per hour. That’ll be true even on the South Taurids’ expected peak night of November 4 (before dawn November 5). The waxing crescent moon sets at early evening, leaving a dark sky for the South Taurid meteors, which are expected to produce the most meteors in the wee hours just after midnight on November 5.
November 11/12, 2012, late night November 11 until dawn November 12 North Taurids
This shower is long-lasting (October 12 – December 2) but modest, and the peak number is forecast at about 7 meteors per hour. Typically, you see the maximum numbers at around midnight to 1 a.m., when Taurus the Bull moves nearly overhead. This year, the thin waning crescent moon won’t rise till close to dawn, leaving a long dark night for these rather slow-moving but sometimes bright North Taurid meteors. you might even see some Taurid fireballs. The greatest numbers of North Taurid meteors come just after midnight on November 12..
November 16/17, 2012, late night November 16 until dawn November 17 Leonids
Radiating from the constellation Leo the Lion, the Leonid meteor shower is famous. Historically, this shower has produced some of the greatest meteor storms in history – at least one in living memory, 1966 – with rates as high as many thousands of meteors per hour. Indeed, on that beautiful night in 1966, the meteors did fall like rain. Some who watched the shower said they felt as if they needed to grip the ground, so strong was the impression of Earth plowing along through space, fording the meteoroid stream. The meteors, after all, were all streaming from a single point in the sky – the radiant point – in this case in the constellation Leo the Lion. Leonid meteor storms sometimes recur in cycles of 33 to 34 years, but the Leonids around the turn of the century – while wonderful for many observers – did not match the shower of 1966. And, in most years, the Lion whimpers rather than roars, producing a maximum of perhaps 10-15 meteors per hour. Like most meteor showers, the Leonids ordinarily pick up steam after midnight and display the greatest meteor numbers just before dawn. In 2012, however, the waxing crescent moon will setting at early evening, leaving a dark night for Leonid meteor shower.
December 13/14, 2012, late night December 13 until dawn December 14 Geminids
The final major meteor shower of every year (unless one surprises us!) is always the December Geminid shower, often producing 50 or more meteors per hour. It is a beloved shower, because, as a general rule, it’s either the August Perseids or the December Geminids that give us the most prolific display of the year. Best of all, the new moon guarantees a dark sky on the peak night of the Geminid shower (mid-evening December 13 until dawn December 14). But the nights on either side of the peak date should be good as well. Unlike many meteor showers, you can start watching the Geminids by 9 or 10 p.m. local time. The peak might be around 2 a.m. local time on these nights, because that’s when the shower’s radiant point is highest in the sky as seen around the world. With no moon to ruin the show, 2012 presents a most favorable year for watching the grand finale of the meteor showers. Best viewing of the Geminids will probably be from about 1 a.m. to 3 a.m. on December 14.
Create your own printable sunrise/sunset calendar (check moon phase and moonrise/moonset boxes).
Tips for watching meteors
Most important: a dark sky. Here’s the first thing – the main thing – you need to know to become as proficient as the experts at watching meteors. That is, to watch meteors, you need a dark sky.
Know your dates and times. You also need to be looking on the right date, at the right time of night. Meteor showers occur over a range of dates, because they stem from Earth’s own movement through space. As we orbit the sun, we cross “meteor streams.” These streams of icy particles in space come from comets moving in orbit around the sun. Comets are fragile icy bodies that litter their orbits with debris. When this cometary debris enters our atmosphere, it vaporizes due to friction with the air. If moonlight or city lights don’t obscure the view, we on Earth see the falling, vaporizing particles as meteors.
What to bring. You can comfortably watch meteors from many places, assuming you have a dark sky: your back yard or deck, the hood of your car, the side of a road. If you want to bring along equipment to make yourself more comfortable, consider a blanket or reclining lawn chair, a thermos with a hot drink, binoculars for gazing along the pathway of the summer Milky Way. Be sure to dress warmly enough. Even the summer nights can be chilly, especially in the hours before dawn when the most meteors should be flying.
Are the predictions reliable? Although astronomers have tried to publish exact predictions in recent years, meteor showers remain notoriously unpredictable. Your best bet is to go outside at the times we suggest, and plan to spend at least an hour reclining comfortably while looking up at the sky.
In 2012, the full moon gets in the way of the May Eta Aquarids. Moon-free nights greet the April Lyrids, the November North Taurids and the December Geminids. Moonlight should not pose much of a problem for the October Draconids, October Orionids, November South Taurids and November Leonids. Some moon-free viewing time is in store for the January Quadrantids and July Delta Aquarids. Our almanac page provides links for access to the moonrise and moonset times in your sky.
Peak dates are derived from data published in the Observer’s Handbook by the Royal Astronomical Society of Canada and Guy Ottewell’s Astronomical Calendar.
Earlier in 2012:
January 4, 2012 in the wee hours before dawn Quadrantids
When we say January 4, we mean in the wee hours before dawn, not that night. Although the waxing gibbous moon lights up most of the night and doesn’t set until roughly 3 a.m. local time, this is about the best time of night to watch for these meteors. Click here to know when the moon sets in your sky. Although the Quadrantids can produce over 100 meteors per hour, the sharp peak only lasts for a few hours, and doesn’t always come at an opportune time. In other words, you have to be in the right spot on Earth to view this meteor shower in all its splendor. If this year’s forecast proves correct, eastern North America, the North Atlantic Ocean and possibly western Europe will be in a fine position to watch this shower. However, meteor showers are notorious for defying predictions. This shower is worth a try at northerly latitudes all around the globe. Face the general direction of north-northeast, but take in as wide an expanse of sky as possible. Watch from about 2 a.m. until dawn.
April 22, 2012 Lyrids
The Lyrid meteors – April’s “shooting stars” – tend to be bright and often leave trails. About 10-20 meteors per hour at peak can be expected. Plus, the Lyrids are known for uncommon surges that can sometimes bring the rate up to 100 per hour. Those rare outbursts are not easy to predict, but they’re one of the reasons the tantalizing Lyrids are worth checking out. The radiant for this shower is in the constellation Lyra, which rises in the northeast at about 10 p.m. Fortunately, in 2012, the new moon guarantees a dark sky in the late night and morning hours, the best time to watch the Lyrid shower. As a general rule, the greatest number of Lyrid meteors fall in the dark hours before dawn.
May 5 and 6, 2012 Eta Aquarids
This shower has a relatively broad maximum but is expected to show the greatest number of meteors before dawn on May 5 or 6. Unfortunately, the closest and largest full moon of 2012 will be out all night long, leaving no dark sky for this year’s Eta Aquarid show. But die-hard meteor enthusiasts will be watching anyway, to see how many Eta Aquarids can be seen in a moonlit sky. At northerly latitudes – for example, in the northern U.S. and Canada, or northern Europe – the meteor numbers are few and far between. In the southern half of the U.S., 10 to 20 meteors per hour might be visible in a dark sky. Farther south – for example, in the Southern Hemisphere – the meteor numbers increase dramatically, perhaps two to three times more Eta Aquarid meteors streaking the southern skies. For the most part, this is a predawn shower. The radiant for this shower appears in the east-southeast at about 4 a.m. local time (the time at all locations) and the hour or two before dawn offers the most meteors. The broad peak to this shower means that some meteors may fly in the dark hour before dawn for a few days before and after the predicted optimal date. Although the most meteors will probably rain down on May 5 or 6 before dawn, the full moon is sure to wash away all but the brightest Eta Aquarid meteors.
July 28 and 29, 2012 Delta Aquarids
Like the Eta Aquarids, this shower favors the Southern Hemisphere, and the tropical latitudes in the Northern Hemisphere. Although the waxing gibbous moon won’t set till after midnight, the hours between moonset and dawn will probably offer the most Delta Aquarid meteors. (Click here to know when the moon sets in your sky.) The meteors appear to radiate from the southern part of the sky. From northern temperate latitudes, the maximum hourly rate may reach 15-20 meteors in a dark sky. Unlike many meteor showers, this one doesn’t have a very definite peak, despite the dates given above. Instead, these medium-speed meteors ramble along fairly steadily throughout late July and early August. An hour or two before dawn usually presents the most favorable view of the Delta Aquarids. Try watching in late July, in the hours between moonset and dawn.
August 10/11, 11/12, and 12/13, 2012 Perseids
Meteors are typically best after midnight, but in 2012, with the moon rising into the predawn sky, you might want to watch for Perseid meteors in late evening as well. You can get moonrise times via this custom sunset calendar. As seen from around the world, the waning crescent moon will rise later on August 12 than on August 11, and, on the morning of August 13, although you’re slightly past the peak, the moon will rise later still. On any of those mornings, moonlight shouldn’t be so overwhelming as to ruin the show. Plus the moon on those mornings will be near the bright planets Venus and Jupiter in the eastern predawn sky. It’ll be a beautiful early morning scene. The Perseids are typically fast and bright meteors. They radiate from a point in the constellation Perseus the Hero. You don’t need to know Perseus to watch the shower because the meteors appear in all parts of the sky. The Perseids are considered by many people to be the year’s best shower, and often peak at 50 or more meteors per hour in a dark sky. The Perseids tend to strengthen in number as late night deepens into midnight, and typically produce the most meteors in the wee hours before dawn. These meteors are often bright and frequently leave persistent trains. Starting in late evening on the nights of August 10/11, 11/12 and 12/13. The Perseid meteors will streak across these short summer nights from late night until dawn, with only a little interference from the waning crescent moon. Plus the moon will be near the bright planets Venus and Jupiter in the eastern predawn sky.
October 7, 2012 Draconids
The radiant point for the Draconid meteor shower almost coincides with the head of the constellation Draco the Dragon in the northern sky. That’s why the Draconids are best viewed from the Northern Hemisphere. The Draconid shower is a real oddity, in that the radiant point stands highest in the sky as darkness falls. Unlike many meteor showers, the Draconids are more likely to fly in the evening hours than in the morning hours after midnight. This shower is usually a sleeper, producing only a handful of languid meteors per hour in most years. But watch out if the Dragon awakes! In rare instances, fiery Draco has been known to spew forth many hundreds of meteors in a single hour. With no moon to interfere during the evening hours, try watching at nightfall and early evening on October 7 and 8.
The
Draconid meteor shower put on a fabulous display in October of last
year (2011). European observers saw over 600 meteors per hour. Image
copyright: Frank Martin Ingilæ. Used with permission. Click here to expand.
EarthSky Facebook friend Dave Walker caught this 2012 Perseid meteor on the morning of August 12, 2012.
A
bright Perseid meteor seen by astrophotographer Stefano De Rosa this
morning (August 12) on the island of Isola D’Elba in Italy. See more of Stefano’s 202 Perseid meteor photos here.
EarthSky Facebook
friend Brian Emfinger captured this amazing view early this morning
(August 12). Not sure if this photo is stacked – I suspect so. Perseid
meteors tend to cross the sky one by one. But this photo captures what
you can expect to see during a burst of meteors – when several at once
cross the sky – or during a particularly rich meteor display. Fantastic
image Brian! Thank you.
An Eta Aquarid meteor streaks over northern Georgia on April 29, 2012. Image credit: NASA/MSFC/B. Cooke
Image Credit: Jimmy Westlake
Bottom line: The Delta Aquarid and Perseid meteor showers combine in late July and August to create what most consider the best and most reliable meteor display for Northern Hemisphere observers. In 2012, watch for the Delta Aquarids from midnight to dawn around late July, when the moon is absent from that part of the sky. Then watch for the Perseids at their peak on the mornings of August 11, 12 and 13. On those August mornings, as an added treat, the moon will be sweeping past the brightest planets – Venus and Jupiter – in the eastern predawn sky. You can’t ask for more!
source : http://earthsky.org/astronomy-essentials/earthskys-meteor-shower-guide
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