With the Eta Aquarid meteor shower behind us – drowned in the glare from the May 5 supermoon – the next big meteor event of 2012 will come in late July and early August. And what an event it is! The Delta Aquarid and Perseid meteor showers combine around that time to create what most consider the best and most reliable meteor display for Northern Hemisphere observers. Woot!
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 12 and 13, 2012 Perseids
And when we say August 12 or 13, we mean the morning hours after midnight – not that night. The waning crescent moon will rise around midnight, only somewhat obscuring the Perseid display during the shower’s actual peak. The moonlight shouldn’t be so overwhelming as to ruin the show. These typically fast and bright meteors 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 at mid to late evening on the nights of August 11/12 and 12/13, watch for the Perseid meteors to streak across this short summer night from late night until dawn, with only a little interference from the waning crescent moon.
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.
October 21, 2012, before dawn. Orionids
With the waxing crescent moon setting before midnight (on October 20), that means a dark sky between midnight and dawn, or during the best viewing hours for the Orionid meteors. On a dark, moonless night, the Orionids exhibit a maximum of about 15 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..
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.
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.
- EarthSky
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