Post by uforn on Aug 9, 2010 18:26:44 GMT 1
EarthSky’s meteor shower guide for 2010
The 2010 Perseid meteor shower – August’s famous ’shooting stars’ – will peak in this coming week, on the mornings of August 12 and 13. The shower has been gradually rising to a peak since early August. Any night this week, you might see Perseid meteors. For more, see below.
August 12 and 13, 2010 Perseids
And when we say August 12 or 13, we mean the morning hours after midnight … not that night. These typically fast and bright meteors radiate from a point in the constellation Perseus the Hero. But you don’t need to know Perseus to watch the shower. 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. 2010 is a great year for the Perseids. This year, the slender waxing crescent moon will set at early evening, leaving a dark sky for this year’s Perseid show. 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. On the mornings of August 12 and 13, watch the Perseid meteors streak across this short summer night from midnight until dawn. Lie back and watch meteors until dawn’s light washes the stars and planets from the sky. The morning of August 11 should be good, too – in fact, this shower tends to rise gradually to a peak for about a week. Then it’s known to drop off rapidly after the peak mornings.
How to find the radiant point of the Perseid meteors
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. For the Perseids, the best time is midnight to dawn on the mornings of August 12 and 13. But you might also see Perseids before those dates, since the shower builds to a peak gradually. Afterwards, it falls off rapidly. The nights before the Perseid’s peak are probably better for meteor-watching than the nights afterwards. 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 you 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.
Meteor showers still to come in 2010
October 7, 8, 2010 Draconids
The radiant point of the Draconid meteor shower almost coincides with the head of the constellation Draco the Dragon, in the northern sky. That’s why it is best viewed from the northern hemisphere. This shower is a real oddity, in the respect that its radiant point is highest in the sky as darkness falls. The shower is definitely a sleeper, producing only a handful of languid meteors per hour in most years. But watch out if the dragon awakes! On occasion, fiery Draco has been known to spew forth hundreds – if not thousands – of meteors in a single hour. An outburt is not predicted for this year, but then, one never knows when an outburt may occur. Since the new moon will fall on October 7, we’re guaranteed of dark nights for observing these meteors. Unlike most meteor showers, more Draconid meteors are likely to fly in the evening than in the morning hours after midnight. Look northward for the very slow-moving Draconid meteors on the evenings of October 7 and 8..
October 21, 2010 Orionids
The almost full moon makes 2010 a very unfavorable year for watching the Orionid meteor shower. Meteor enthusiasts may try their luck anyway. The Orionids tend to be fast, occasionally leaving persistent trains and producing bright fireballs. On a dark, moonless night, this shower exhibits a maximum of about 15 meteors per hour. If you trace these meteors backward, they seem to originate from the north of Orion’s bright ruddy star Betelgeuse. The Orionids have a broad and irregular peak that is difficult 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 time will probably be one to two hours before dawn on October 21. However, the light of the waxing gibbous moon will wash out all but the brightest Orionid meteors.
November 5, 2010 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 South Taurids are extremely long lasting (September 17 – November 27), but usually don’t offer a whole lot more than about 7 meteors per hour, even on the expected peak date of November 5. Fortunately, the new moon falls on November 6, providing dark skies for this year’s South Taurid meteors. Try the night of November 4-5. The greatest number of meteors generally fall around midnight to one in the morning, when the constellation Taurus the Bull rides high in the sky..
November 12, 2010 North Taurids
Like the South Taurids, this shower is long lasting (October 12 – December 2) but modest, and the peak number is forecast at about 7 meteors per hour. Because the South and North Taurids overlap, there’s some chance of catching a few extra meteors in the mix. Typically, you see the maximum numbers at around midnight to 1 a.m., when Taurus the Bull flies nearly overhead. This year, the waxing crescent moon will set by mid-evening, making 2010 a favorable year for watching these rather slow-moving but sometimes bright North Taurid meteors. Expect to see the greatest numbers at late night and after midnight on the night November 11-12. A few days before and after may offer good viewing as well.
November 17, 2010 Leonids
Historically, the Leonids have produced some of the greatest meteor storms in history, with rates as high as many thousands of meteors per hour. These storms sometimes recur in cycles of 33 to 34 years. Most years, the Lion whimpers rather than roars, producing a maximum of perhaps 10-15 meteors per hour. Although the waxing gibbous moon shines till after midnight, the Leonids will likely be at their best after the moon sets for the night. Like the October Orionids, the Leonids ordinarily pick up steam after midnight and put out the greatest meteor numbers just before dawn. So here’s our suggestion for 2010. Try watching between midnight and dawn on November 17 and November 18. The most Leonids will probably fly in the wee hours before dawn, or after moonset.
December 13-14, 2010 Geminids
This year is fairly favorable for the Geminids, the year’s grand finale. As a general rule, it’s either the Geminids or the August Perseids that give us the most prolific meteor display of the year. Unlike many meteor showers, you can start watching for the Geminids around 9:00 to 10:00 p.m. – in years when the moon is out of the sky. Unfortunately, the waxing gibbous moon obtrudes on the evening hours this year, and doesn’t set till around midnight. However, this shower tends to gain strength after midnight and to climax at roughly 2:00 in the morning. So look for the Geminids to be at their best after moonset. With maximums commonly reaching 50 or more meteors per hour, this is a glorious time of year to sprawl out on your reclining lawn chair and to take in the show. Just be sure to bring along warm clothing, blankets or sleeping bags, and a thermos with a warm beverage. With the waxing gibbous moon setting around mignight, the stage is set for a dark sky and a grand Geminid display. The best viewing of these often bright, medium-speed meteors should be from late night December 13 till dawn December 14.
Earlier in 2010
January 3, 2010 Quadrantids
With the moon just past full phase, the moon-drenched skies will make this a very unfavorable year for watching the Quadrantid shower. The greatest number of meteors tend to fall in the dark hours before dawn. Although the Quadrantids can produce over 100 meteors per hour, the sharp peak only lasts for an hour or two, and doesn’t always peak during the nighttime hours. Face the general direction of north-northeast, but take in as wide an expanse of sky as possible. Unless you are a die-hard meteor observer, you can write this shower off till next year.
April 22, 2010 Lyrids
The Lyrid meteors – April’s “shooting stars” – tend to be bright and often leave trails. About 10-20 meteors per hour at peak are to be expected. Uncommon surges can sometimes bring the rate up to 100 per hour, but these rare outbursts are not easy to predict. That’s one of the reasons why the tantalizing Lyrids are worth watching. The radiant is in the constellation Lyra, which rises in the northeast at about 10 p.m. Although the waxing gibbous moon obstructs the evening and late-night hours, the best time to view the Lyrid shower is in the dark hours before dawn. At that time the moon will be under the horizon. Likely, the optimal night will be between midnight and dawn on Thursday, April 22. But a day or two before and after the peak date may offer a decent sprinkling of meteors too.
May 5, 6 and 7, 2010 Eta Aquarids
The shower has a relatively broad maximum but is expected to put out the greatest number of meteors before dawn on May 6. Unfortunately, the last quarter moon does not bode well for this year’s Eta Aquarid show. At mid-northern latitudes, 10 to 15 meteors per hour are visible in a dark, moonless sky. Farther south – like in the southern hemisphere – the meteor numbers increase dramatically. This is strictly a predawn shower, however, not to take stage this year till after the last quarter moon rises into the sky! The radiant for this shower appears in the east-southeast at about 4 a.m. and the hour or two before dawn is the best viewing time – in years when the moon is out of the sky. The broad peak to this shower means that some meteors may fly a for few days before and after the optimal date. Although the most meteors will probably rain down on May 6 before dawn, the last quarter moon will pretty much wash out this year’s Eta Aquarid shower.
July 29, 2010 Delta Aquarids
Like the Eta Aquarids, this shower favors the southern hemisphere, and the tropical latitudes in the northern hemisphere. 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 is a dark sky. Unlike many meteor showers, this one doesn’t have a very definite peak, despite the date 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, in years when the moon is out of the sky. However, from July 28-30, the waning gibbous moon will fill the sky with moonlight, making this an unfavorable year for the Eta Aquarids. Gear up instead for the peak of the Perseids in August.
In 2010, the moon gets in the way of the January Quadrantids, May Eta Aquarids, July Delta Aquarids and the October Orionids. Moon-free nights greet the August Perseids, considered by many to be the best shower of them all, the hard-to-predict October Draconids and the November South Taurids. Showers that enjoy at least some cover of darkness include the April Lyrids, November North Taurids, November Leonids, and December Geminids. 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.
Source:
earthsky.org/astronomy-essentials/earthskys-meteor-shower-guide