A Possible Meteor Shower from Comet ISON?


Hey, remember Comet C/2012 S1 ISON? Who can forget the roller-coaster ride that the touted “Comet of the Century” took us on last year. Well, ISON could have one more trick up its cosmic sleeve –although it’s a big maybe — in the form of a meteor shower or (more likely) a brief uptick in meteor activity this week.

In case you skipped 2012 and 2013, or you’re a time traveler who missed their temporal mark, we’ll fill you in on the story thus far.

Comet ISON was discovered by Artyom Novichonok and Vitali Nevski on September 21st, 2012 as part of the ongoing International Scientific Optical Network (ISON) survey. Shortly after its discovery, researchers knew they had spotted something special: a sungrazing comet already active at over 6.4 Astronomical Units (A.U.s) from the Sun. The Internet then did what it does best, and promptly ran with the story. There were no shortage of Comet ISON conspiracy theories for science writers to combat in 2013. It’s still amusing to this day to see predictions for comet ISON post-perihelion echo through calendars, almanacs and magazines compiled and sent to press before its demise.

ISON back in the day. Credit-Efrain Morales Rivera, Jaicoa Observatory Aguadilla, Puerto Rico
ISON back in the day. Credit-Efrain Morales Rivera, Jaicoa Observatory Aguadilla, Puerto Rico

The frenzy for all things ISON reached a crescendo on U.S. Thanksgiving Day November 28th 2013, as ISON passed just 1.1 million kilometres from the surface of the Sun. Unfortunately, what emerged was a sputtering ember of the comet formerly known as ISON, which faded from view just as it was slated to reenter the dawn sky.

Hey, we were crestfallen as well… we had our semi-secret dark sky site pre-selected for ISON imaging post-perihelion and everything. Despite heroic searches by ground and space-based assets, we’ve yet to see any compelling recoveries of Comet ISON post-perihelion.

This week, however, Comet ISON may put on its last hurrah, in the form of a minor meteor shower. We have to say from the outset that we’re highly skeptical that an “ISON-id meteor outburst” will grace the skies. Known annual showers are fickle enough, and it’s nearly impossible to predict just what might happen during a meteor shower with no past track record.

But you won’t see anything if you don’t try. If anything is set to occur, the night of January 15th into the 16th might just be the time to watch. This is because the Earth will cross the orbital plane of ISON’s path right around 9:00 PM EST/2:00 UT. Last year, ISON passed within 3.3 million kilometres of the Earth’s orbit on its inbound leg. Earlier last year, ISON was estimated to have been generating a prodigious amount of dust, at a rate of about 51,000 kilograms per minute. Any would-be fragments of ISON outbound would’ve passed closest to the Earth at 64 million kilometres distant on the day after Christmas last year. Veteran sky observer Bob King wrote about the prospects for catching ISON one last time during this month back in December 2013.

Credit: NASA/JPL Solar System Dynamics Small Body Database Browser.
A simulation showing Earth crossing the plane of Comet ISON’s orbit early on January 16th. Credit: NASA/JPL Solar System Dynamics Small Body Database Browser.

Another idea out there that is even more unlikely is the proposal that dust from Comet ISON may generate an uptick in noctilucent cloud activity. And already, a brief search of the internet sees local news reports attempting to tie every meteor observed to ISON this week, though no conclusive link to any observed fireball has been made.

The radiant to watch for any possible “ISON-ids” sits near the +3.5 magnitude star Eta Leonis in the sickle of Leo. Robert Lundsford of the American Meteor Society notes in a recent posting that any ISON-related meteors would pass through our atmosphere at a moderate 51 kilometres a second, with a visible duration of less than one second.

Note that meteor activity has another strike against it, as the Moon reaches Full on the same night. In fact, the Full Moon of Wednesday January 15th sits in the constellation Gemini,just 32 degrees away from the suspect radiant!

Another caveat is in order for any remaining dooms-dayers: no substantial fragments of ISON are (or ever were) inbound and headed towards our fair planet. Yes, we’re seeing rumblings to this effect in the pseudoscience netherworlds of ye ole Internet, along with ideas that ISON secretly survived, NASA “hid” ISON, ISON cloaked like a Romulan Bird of Prey, you name it. Just dust grains, folks… a good show perhaps, but nothing more.

As near as we can tell, talk of a possible meteor shower generated from Comet ISON goes all the way back to a NASA Science News article online from April 2013. Radio observers of meteor showers should be alert for a possible surge in activity this week as well, and it may be the case that more radio “pings” will be noted than visual activity what with the light-polluting Full Moon in the sky. The radiant for any would-be “ISON-ids” transits highest in the sky for northern hemisphere observers at around 2 AM local.

But despite what it has going against it, we’d be thrilled if ISON put on one last show anyhow. It’s always worth watching for meteor activity and noting the magnitude and from whence the meteor came to perhaps note the pedigree as to the shower it might belong to.

The next annual dependable meteor shower won’t be until the night of April 21st to the 22nd, when the Spring Lyrids are once again active. And this year may just offer a special treat on May 24th, when researchers have predicted that the Earth may encounter debris streams laid down by Comet 209P LINEAR way back in 1803 and 1924… Camelopardalids, anyone? Now, that’s an exotic name for a meteor shower that we’d love to see trending!

-Catch sight of any “ISON-ids?” we’d love to see ‘em… be sure to post said pics at Universe Today’s Flickr pool.



The Quadrantid Meteor Shower-One of the Best Bets for 2014

The modern radiant of the Quadrantid meteor shower. (Photo and grahpics by author).

If there’s one thing we love, it’s a good meteor shower from an obscure and defunct constellation.

Never heard of the Quadrantids?  It may well be because this brief but intense annual meteor shower occurs in the early days of January. Chilly temps greet any would be meteor watchers with hardly the balmy climes of showers such as the August Perseids. Still, 2014 presents some good reasons to brave the cold in the first week of January, to just possibly catch the best meteor shower of the year.

The Quadrantids – sometimes simply referred to as “the Quads” in hipster meteor watcher inner circles – peak on January 3rd around 19:30 Universal Time (UT) or 2:30 PM Eastern Standard Time (EST). This places the northern Asia region in the best position to watch the show, though all northern hemisphere observers are encouraged to watch past 11 PM local worldwide. Remember: meteor showers are fickle beasties, with peak activity often arriving early or late. The Quadrantids tie the December Geminids for the highest predicted Zenithal Hourly Rate (ZHR) for 2014 at 120.

A 2012 Quadrantid meteor in the bottom left side of the frame. (Photo by Author).
A 2012 Quadrantid meteor in the bottom left side of the frame. (Photo by Author).

Though the Quads are active from January 1st to the 10th, the enhanced peak only spans an average of six to ten hours. Though high northern latitudes have the best prospects, we’ve seen Quads all the way down in  the balmy January climes of Florida from around 30 degrees north.

Rates for the Quads are typically less than 10 per hour just a day prior to the sharp peak. The moonless mornings of Friday, January 3rd and Saturday, January 4th will be key times to watch. The radiant for the Quads stands highest just hours before local sunrise.

So, what’s up with the unwieldy name? Well, the Quadrantids take their name from a constellation that no longer exists on modern star charts. Along with the familiar patterns such as Leo and Orion, exist such archaic and obscure patterns as “The Printing Office” and the “Northern Fly” that, thankfully, didn’t make the cut. Quadrans Muralis, or the Mural Quadrant, established by Jérome de Lalande in the 1795 edition of Fortin’s Celestial Atlas was one such creation.  A mural quadrant was a large arc-shaped astronomical tool used for measuring angles in the sky. Apparently, Renaissance astronomers were mighty proud of their new inventions, and put immortalized them in the sky every chance they got as sort of the IPhone 5’s of their day.

The outline of the Mural Quadrant against the backdrop of modern day constellations. (Photo and graphic by author).
The outline of the Mural Quadrant against the backdrop of modern day constellations. (Photo and graphic by author).

The Mural Quadrant spanned the modern day constellations of Draco, Hercules and Boötes. The exact radiant of the Quads lies at Right Ascension 15 Hours 18’ and declination 49.5 degrees north, in the modern day constellation Boötes just 15 degrees east of the star Alkaid.

Previous year’s maximum rates as per the IMO have been as follows:

2013: ZHR=129

2012: ZHR=83

2011: ZHR=90

2010: ZHR=No data (Bright waning gibbous Moon)

2009: ZHR=138

The parent source of the Quadrantids went unknown, until Peter Jenniskens proposed that asteroid 2003 EH1 is a likely suspect. Possibly an extinct comet, 2003 EH1 reaches perihelion at 1.2 AUs from the Sun in 2014 on March 12th, another reason to keep an eye on the Quads in 2014. 2003 EH1 is on a 5.5 year orbit, and it’s been proposed that the asteroid may have a connection to comet C/1490 Y1 which was observed and recorded by 15th century astronomers in the Far East.

The Quadrantids were first identified as a distinct meteor shower in the 1830s by European observers. Owing to their abrupt nature and their climax during the coldest time of the year, the Quadrantids have only been sporadically studied. It’s interesting to note that researchers modeling the Quadrantid meteor stream have found that it undergoes periodic oscillations due to the perturbations from Jupiter. The shower displays a similar orbit to the Delta Aquarids over a millennia ago, and researchers M. N. Youssef and S. E. Hamid proposed in 1963 that the parent body for the shower may have been captured into its present orbit only four thousand years ago.

The orbital path of Amor NEO asteroid 196256 2003 EH1. (Credit: NASA/JPL Solar System Dynamics Small-Body Database Browser).
The orbital path of Amor NEO asteroid 196256 2003 EH1. (Credit: NASA/JPL Solar System Dynamics Small-Body Database Browser).

2003 EH1 is set to resume a series of close resonnance passes of Earth and Jupiter in 2044, at which time activity from the Quads may also increase. It’s been proposed that the shower may fade out entirely by the year 2400 AD.

And the Quadrantids may not be the only shower active in the coming weeks. There’s been some discussion that the posthumous comet formerly known as ISON might provide a brief meteor display on or around the second week of January.

Be sure to note any meteors and the direction that they’re coming from: the International Meteor Organization and the American Meteor Society always welcomes any observations. Simple counts of how many meteors observed and from what shower (Quads versus sporadics, etc) from a given location can go a long way towards understanding the nature of this January shower and how the stream is continually evolving.

Stay warm, tweet those meteors to #Meteorwatch, and send those brilliant fireball pics in to Universe Today!