Nov 8, 2015

EarthSky’s Meteor Shower Guide For 2015

[Note: Only the most current portion of the article has been posted. To view the entire article and help aids, a link is provided at the conclusion of this posting.]

Yay! Meteor season! October features two noteworthy meteor showers – the Draconids early in the month, and the Orionids later on – plus there’s a chance to watch for Taurid meteors. Follow the links below to learn what to expect for those meteor showers and for meteor showers during the rest of 2015.

Throughout October, 2015 South Taurids?

October 21-22, 2015 Orionids

November 4-5, 2015 South Taurids

November 12-13, 2015 North Taurids

November 17-18, 2015 Leonids

December 13-14, 2015 Geminids

Remember …

October 8, 2015, the 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. That means that, unlike many meteor showers, more Draconids are 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. In 2015, the waning crescent moon rises at late night and will not intrude on this year’s Draconid shower. Try watching at nightfall and early evening on October 8 and 9.

October 22, 2015 before dawn, the Orionids

On a dark, moonless night, the Orionids exhibit a maximum of about 10 to 20 meteors per hour. The waxing gibbous moon will be out the during the evening hours, but it’ll set before the prime time viewing hours, providing deliciously dark skies for this year’s Orionid shower. More meteors tend to fly after midnight, and the Orionids are typically at their best in the wee hours before dawn. These fast-moving meteors occasionally leave persistent trains. They sometimes produce bright fireballs, so watch for them to flame in the sky. 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. This year, 2015, presents a fine year for watching the Orionid meteor shower. The best viewing for the Orionids in 2015 will probably be before dawn on October 22. Try the days before and after that, too, sticking to the midnight-to-dawn hours..

Late night November 4 until dawn November 5, 2015, the South Taurids

Fortunately, the full moon will wash away all but the brightest South Taurid meteors. The meteoroid streams that feed the South (and North) Taurids are very spread out and diffuse. 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 is true even on the South Taurids’ expected peak night. The Taurids are, however, well known for having a high percentage of fireballs, or exceptionally bright meteors. Plus, the other Taurid shower – the North Taurids – always adds a few more meteors to the mix during the South Taurids’ peak night. In 2015, the slim waning crescent moon coming up before dawn will not seriously obtrude on this year’s South Taurid meteor shower. The South Taurids should produce their greatest number of meteors in the wee hours – between midnight and dawn – on November 5. Remember, it’ll be possible to catch a fireball or two!

Late night November 12 until dawn November 13, 2015, the North Taurids

Like the South Taurids, the North Taurids meteor shower is long-lasting (October 12 – December 2) but modest, and the peak number is forecast at about 7 meteors per hour. The North and South Taurids combine, however, to provide a nice sprinkling of meteors throughout October and November. Typically, you see the maximum numbers at around midnight, when Taurus the Bull is highest in the sky. Taurid meteors tend to be slow-moving, but sometimes very bright. In 2015, the new moon comes only one day before the predicted peak, providing a dark sky for the 2015 North Taurid shower.

Late night November 17 until dawn November 18, 2015, the Leonids

Radiating from the constellation Leo the Lion, the famous Leonid meteor shower has produced some of the greatest meteor storms in history – at least one in living memory, 1966 – with rates as high as thousands of meteors per minute during a span of 15 minutes on the morning of November 17, 1966. Indeed, on that beautiful night in 1966, the meteors did, briefly, fall like rain. Some who witnessed the 1966 Leonid meteor storm 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 on a dark night. Like many meteor showers, the Leonids ordinarily pick up steam after midnight and display the greatest meteor numbers just before dawn. In 2015, the rather wide waxing crescent moon sets in the evening and won’t interfere with this year’s Leonid meteor shower. The peak morning will probably be November 18 – but try November 17, too.

December 13-14, 2015, mid-evening until dawn, Geminids

Radiating from near the bright stars Castor and Pollux in the constellation Gemini the Twins, the Geminid meteor shower is one of the finest meteors showers visible in either the Northern or the Southern Hemisphere. Best yet, there is no moon to obscure the 2015 Geminid shower. The meteors are plentiful, rivaling the August Perseids, with perhaps 50 to 100 meteors per hour visible at the peak. Plus Geminid meteors are often bright. These meteors are often about as good in the evening as in the hours between midnight and dawn. In 2015, the slender waxing crescent moon will set soon after the sun, providing a wonderful cover of darkness for the Geminid meteor shower. Your best bet is to watch on December 12-13 and 13-14, from mid-evening (9 to 10 p.m.) until dawn.

A word about moonlight. In 2015, moonlight will not pose much of a problem for the April Lyrids, August Perseids, October Draconids, October Orionids, November South Taurids, November North Taurids, November Leonids and December Geminids. There’s some moon-free viewing time for the July Delta Aquarids. The nearly full moon gets in the way of the January Quadrantids and May Eta Aquarids. Our almanac page provides links for access to the moonrise and moonset times in your sky.

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. It’s possible to catch a meteor or two or even more from the suburbs. But, to experience a true meteor shower – where you might see several meteor each minute – avoid city lights.

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. The Lyrids take place between about April 16 and 25. The peak morning in 2015 should be April 22, but you might catch Lyrid meteors on the nights around that date as well.

Where to go to watch a meteor shower. You can comfortably watch meteors from many places, assuming you have a dark sky: a rural back yard or deck, the hood of your car, the side of a road. State parks and national parks are good bets, but be sure they have a wide open viewing area, like a field; you don’t want to be stuck in the midst of a forest on meteor night. An EarthSky friend and veteran meteor-watcher and astrophotographer Sergio Garcia Rill also offers this specific advice:

    … you might want to give it a try but don’t know where to go. Well, in planning my night photoshoots I use a variety of apps and web pages to know how dark the sky is in a certain location, the weather forecast, and how the night sky will look. Here’s the link to Dark Sky Finder. It’s a website that shows the light pollution in and around cities in North America which has been fundamental for finding dark sites to setup shots. Dark Sky finder also has an app for iPhone and iPad which as of this writting is only 99 cents so you might want to look into that as well. For people not in North America, the Blue Marble Navigator might be able to help to see how bright are the lights near you.

    The other tool I can suggest is the Clear Sky Chart. I’ve learned the hard way that, now matter how perfectly dark the sky is at your location, it won’t matter if there’s a layer of clouds between you an the stars. This page is a little hard to read, but it shows a time chart, with each column being an hour, and each row being one of the conditions like cloud coverage and darkness. Alternatively, you could try to see the regular weather forecast at the weather channel or your favorite weather app.

What to bring with you. You don’t need special equipment to watch a meteor shower. 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 at the stars. Be sure to dress warmly enough, even in spring or summer, especially in the hours before dawn. Binoculars are fun to have, too. You won’t need them for watching the meteor shower, but, especially if you have a dark sky, you might not be able to resist pointing them at the starry sky.

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, if not a whole night, reclining comfortably while looking up at the sky. Also remember that meteor showers typically don’t just happen on one night. They span a range of dates. So the morning before or after a shower’s peak might be good, too.

Remember … meteor showers are like fishing. You go, you enjoy nature … and sometimes you catch something.

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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