Here Comes the Weekend Leonid Meteor Shower!

November 2013 offers a chance to catch a dependable meteor shower, albeit on an off year. The Leonid meteors are set to reach their annual peak this coming weekend on Sunday, November 17th. We say it’s an off-year, but not that it should discourage you from attempting to catch the Leonids this weekend in the early dawn.

Projections for 2013 suggest a twin-peaked maximum, with the first peak arriving on November 17th at 10:00 UT/5:00 AM EST favoring North America, and the second one reaching Earth on the same date six hours later at 16:00 UT/11:00, favoring the central Pacific.

Unfortunately, the Full Moon also occurs the on very date that the Leonids peak at 10:16 AM EST/ 15:16UT, right between the two peaks! This will definitely cut down on the number of meteors you’ll see in the early AM hours.

That’s strike one against the 2013 Leonids. The next is the curious sporadic nature of this shower. Normally a minor shower with a zenithal hourly rate (ZHR) in the range of 10-20 per hour, the Leonids are prone to great storms topping a ZHR of 1,000+ every 33 years. We last experienced such an event in 1998 and 1999, and we’re now approaching the mid-point lull between storms in the 2014-2016 time frame.

An early Leonid meteor captured last week from the United Kingdom Meteor Observing Network's Church Crookham station. (Credit: UKMON/Peter-Campbell-Burns).
An early Leonid meteor captured last week from the United Kingdom Meteor Observing Network’s Church Crookham station. (Credit: UKMON/Peter-Campbell-Burns).

Still, this is one shower that’s always worth monitoring. The source of the Leonids is Comet 55p/Tempel-Tuttle, which is on a 33-year orbit and is due to reach perihelion again in 2031.

Note that the Leonids have also continued to show enhanced activity in past years even when the Moon was a factor:

2012- ZHR=47.

2011- ZHR=22, Moon=8% waning gibbous.

2010- ZHR=40, 86% waxing gibbous.

2009- ZHR=79.

2008-70 ZHR=72% waning gibbous

We even managed to observe the Leonid meteors from Vail, Arizona in 2002 and 2005, on years when the Moon was nearly Full.

Now, for the good news. The Leonids have a characteristic r value of 2.5, meaning that they produce a higher than normal ratio of fireballs. About 50-70% of Leonid meteors are estimated to leave persistent trains, a good reason to keep a pair of binoculars handy. And hey, at least the 2013 Leonids peak on the weekend, and there’s always comet’s ISON, X1 LINEAR, 2P/Encke and R1 Lovejoy to track down to boot!

A 2002 Leonid captured over Redstone Arsenal, Alabama. (Credit: NASA/MSFC/MEO/Bill Cooke).
A 2002 Leonid captured over Redstone Arsenal, Alabama. (Credit: NASA/MSFC/MEO/Bill Cooke).

Here’s a few tips and tricks that you can use to “beat the Moon” on your Leonid quest. One is to start observing now, on the moonless mornings leading up to the 17th. You’ll always see more Leonid meteors past local midnight as the radiant rises to the northeast. This is because you’re standing on the portion of the Earth turning forward into the meteor stream. Remember, the front windshield of your car (the Earth) always collects the most bugs (meteors). Observers who witnessed the 1966 Leonid storm reported a ZHR in excess of thousands per hour, producing a Star Trek-like effect of the Earth plowing through a “snowstorm” of meteors!

The radiant of the Leonids sits in the center of the backwards question mark asterism of the “Sickle” in the astronomical constellation Leo (hence name of the shower).

You can also improve your prospects for seeing meteors by blocking the Moon behind a building or hill. Though the Leonids will appear to radiate from Leo, they can appear anywhere in the sky. Several other minor showers, such as the Taurids and the Monocerotids, are also active in November.

Meteor shower photography is simple and can be done with nothing more than a DSLR camera on a tripod. This year, you’ll probably want to keep manual exposures short due to the Full Moon and in the 20 seconds or faster range. Simply set the camera to a low f-stop/high ISO setting and a wide field of view and shoot continuously. Catching a meteor involves luck and patience, and be sure to examine the frames after a session; every meteor I’ve caught on camera went unnoticed during observation! Don’t be afraid to experiment with different combinations to get the sky conditions just right. Also, be sure to carry and extra set of charged camera batteries, as long exposures combined with chilly November mornings can drain DSLR batteries in a hurry!

A Woodcut print depicting the 1933 Leonids as seem from Niagara Falls. (Wikimedia Commons image in the Public Domian).
A Woodcut print depicting the 1933 Leonids as seem from Niagara Falls. (Wikimedia Commons image in the Public Domain).

The Leonids certainly have a storied history, dating back to before meteors where understood to be dust grains left by comets. The 1833 Leonids were and awesome and terrifying spectacle to those who witnessed them up and down the eastern seaboard of the U.S. In fact, the single 1833 outburst has been cited as contributing to the multiple religious fundamentalist movements that cropped up in the U.S. in the 1830s.

We witnessed the 1998 Leonids from the deserts of Kuwait while stationed at Al Jabber Air Base. It was easily one of the best meteor displays we ever saw, with a ZHR reaching in access of 500 per hour before dawn. It was intense enough that fireballs behind us would often light up the foreground like camera flashes!

Reporting rates and activity for meteor showers is always fun and easy to do — its real science that you can do using nothing more than a stopwatch and your eyes. The International Meteor Association is always looking for current meteor counts from observers. Data goes towards refining our understanding and modeling of meteor streams and future predictions. The IMO should also have a live ZHR graph for the 2013 Leonids running soon.

Have fun, stay warm, send those Leonid captures in to Universe Today, and don’t forget to tweet those meteors to #Meteorwatch!

The Curious History of the Lyrid Meteor Shower

Today we residents of planet Earth meet up with a meteor stream with a strange and bizarre past.

The Lyrid meteors occur annually right around April 21st to the 23rd. A moderate meteor shower, observers in the northern hemisphere can expect to see about 20 meteors in the early morning hours under optimal conditions. Such has been the case for recent years past, and this year’s presence of a waxing gibbous Moon has lowered prospects for this April shower considerably in 2013.

But this has not always been the case with this meteor stream. In fact, we have records of the Lyrids stretching back over the past 2,600 years, farther back than any other meteor shower documented.

The earliest account of this shower comes from a record made by Chinese astronomers in 687 BC, stating that “at midnight, stars dropped down like rain.” Keep in mind that this now famous assertion that is generally attributed to the Lyrids was made by mathematician Johann Gottfried Galle in 1867. It was Galle along with Edmond Weiss who noticed the link between the Lyrids and Comet C/1861 G1 Thatcher discovered six years earlier.

Comet Thatcher was discovered on April 5th, 15 days before it reached perihelion about a third of an astronomical unit (A.U.) from the Earth. Comet Thatcher a periodic comet on a 415 year long orbital period.

But in the early to mid-19th century, the very idea that meteor showers were linked to comets or even non-atmospheric phenomena was still hotly contested.

One singular event more than any other triggered this realization. The Leonid meteor storm of 1833 in the early morning hours of November 13th was a stunning and terrifying spectacle for residents of the U.S eastern seaboard. This shower produces mighty outbursts, often topping a Zenithal Hourly Rate (ZHR) of over a 1,000 once every 33 to 34 years. I witnessed a fine outburst of the Leonids from Kuwait in 1998, and we may be in for a repeat performance from this shower around 2032 or 2033.

There is substantial evidence that the Lyrids may also do the same at an undetermined interval. On April 20th 1803, one of the most famous accounts of a “Lyrid meteor storm” was observed up and down the United States east coast. For example, one letter to the Virginia Gazette states;

“From one until three, those starry meteors seemed to fall from every point in the sky heavens, in such numbers as to resemble a shower of sky rockets.”

Another account published in the Raleigh, North Carolina Register states that:

“The whole hemisphere as far as the extension of the horizon seemed illuminated; the meteors kept no particular direction but appeared to move in every way.”

study of the 1803 Lyrid outburst by W.J. Fisher cites over a dozen accounts of the event and is a fascinating read. Viewers were also primed for the event by the dramatic Leonid storm of 1799 four years earlier.

Interestingly, the Moon was only one day from New phase on the night of the 1803 Lyrids. Prime meteor watching conditions.

An unrelated meteorite fall would also occur four years later over Weston, Connecticut on December 14th, 1807 as recounted by Kathryn Prince in A Professor, A President, and a Meteor. These events would place Yankee politics at odds with the origin of meteors and rocks from the sky.

An apocryphal quote is often attributed to President Thomas Jefferson that highlights the controversy of the day, saying that “I would more easily believe that two Yankee professors would lie than that stones would fall from heaven.”

While both are of cosmogenous origin, no meteorite fall has ever been linked to a meteor shower, which is spawned by dust debris from comets. For example, many in the media erroneously speculated that the Sutter’s Mill meteorite that fell to Earth on the morning of April 22nd, 2012 was in fact a Lyrid meteor.

But a Lyrid may be implicated in another unusual 19th century observation. On April 24th 1874, a professor Scharfarik of Prague, Czechoslovakia was observing the daytime First Quarter Moon with his 4” refractor. The good professor was surprised by an “Apparition on the disc of the Moon of a dazzling white star,” which was “quite sharp and without a perceptible diameter.” Possible suspects are a telescopic meteor moving towards or along the observers’ line of sight or perhaps a Lyrid impacting the dark limb of the Moon.

Moving into the 20th century, rates for the Lyrids have stayed in the ZHR=20 range, with notable peaks of 100+ per hour noted by Japanese observers in 1922 and 100 per hour noted by U.S. observers in 1982.

It should also be noted that another less understood shower radiates from the constellation Lyra in mid-June. First noted Stan Dvorak while hiking in the San Bernardino Mountains in 1966, the June Lyrids produce about 8-10 meteors per hour from June 10 to the 21st. The source of this newly discovered shower is thought to be Comet C/1915 C1 Mellish.

A June Lyrid may have even made its way into modern fiction. As recounted in a July 2004 issue of Sky & Telescope, researchers Marilynn & Donald Olson note the following line from James Joyce’s Ulysses:

“A star, precipitated with great apparent velocity across the firmament from Vega in the Lyre above the zenith.”

Joyce seems to be describing a June Lyrid decades before the shower was officially recognized. The constellation Lyra rides high in the early morning sky for mid-northern latitudes in the early summer months.

All interesting concepts to ponder as we keep an early morning vigil for the Lyrids this week. Could there be more Lyrid storms in the far off future, as Comet Thatcher reaches perihelion once again in the late 23rd century? Could more historical clues of the untold history of this and other showers be awaiting discovery?

Somewhat closer to us in time and space, Paul Wiegert of the University of Ontario has also recently speculated that Comet 2012 S1 ISON may provoke a meteor shower on January 12th, 2014. Regardless of whether ISON turns out to be the “Comet of the Century,” this could be one to watch out for!