11/22/19 – ALPHA MONOCEROTID METEOR UPDATE:
Earth passed by a filament of comet dust on November 22nd around 12:50 a.m. EDT. The close encounter did produce some Alpha Monocerotid meteors, but it was not a strong outburst as expected. Spaceweater.com has received reports from Germany (15 meteors), Georgia, USA (24 meteors), the Netherlands (2 meteors), North Carolina, USA (~10 meteors), and Norway (5 meteors). These modest counts appear to be typical.
Meteorologist Joe Rao in New York listened to a forward scatter meteor radar and noticed a sharp uptick in echoes. Perhaps an outburst did occur but was dominated by faint meteors mostly invisible to the naked eye. If you saw anything, contact [email protected].
Like shooting stars? Then you’ll want to make a concerted effort to look skyward on Thursday night, November 21st, 2019, when a brief bevy of them could streak out of the east-southeast sky. This is when the Alpha Monocerotids meteor shower is due to reach its peak. And while you may have never heard of this meteor shower, this year you might want to check it out.
Why Are They Called The Alpha Monocerotids?
These meteors get their name from the large, dull constellation of Monoceros, the Unicorn, composed chiefly of faint stars. The meteors will appear to emanate from a spot in the sky not far from the bright yellowish-white star Procyon in the neighboring constellation of Canis Minor, the Little Dog.
The Alpha Monocerotids are never mentioned in most astronomy guidebooks because little or no activity is usually seen from them. Certainly, nothing to compare to the far more prolific and reliable annual meteor displays like the August Perseids and December Geminids. So why bother with a meteor shower that almost nobody has heard of?
Well, every once in a great while a short-lived “outburst” of meteors has been reported from the Alpha Monocerotid shower. Outbursts are very short but intense meteor showers, also known as meteor storms, and this year, it’s looking likely for this kind of activity.
Get Ready for an Outburst!
Alpha Monocerotids outbursts are extremely infrequent, having been definitively seen on only four occasions during the last 100 years: 1925, 1935, 1985 and 1995. There were very few witnesses for the first three occasions because these sudden outbursts were totally unexpected.
In 1995, Dr. Peter Jenniskens, a senior research scientist with the SETI Institute and NASA’s Ames Research Center, put out an alert stating that he believed that another Alpha Monocerotid outburst would take place on the night of November 21st over Europe. Dr. Jenniskens and a team of meteor observers from the Netherlands were carefully watching the sky that night from an observatory in Spain.
He later wrote:
Suddenly, (we saw in quick succession) three meteors. And this time it did not stop after just a few. Meteors started pouring out of the sky, falling left and right, up and down. Bright meteors too. Meteors were falling at a rate of five or more per minute. Then just twenty minutes later it was all over.
Now, another alert has been issued for another possible meteor outburst this Thursday night.
This latest forecast is again based on calculations made by Dr. Jenniskens, in collaboration with a highly regarded meteor expert, Esko Lyytinen of Finland.
Cosmic Comet Debris
From observations of the previous meteor outbursts, both men have concluded that the Alpha Monocerotids are the leftover debris from a comet, previously unknown and still unseen, which is hypothesized to take almost 600 years to make one trip around the sun. The last time this supposed comet swept through the inner solar system, it likely left behind a long, thin, concentrated trail of dust.
Very occasionally, in its annual path around the sun, our Earth has happened to wander into that dust trail. Based on the previous four outbursts, these interactions haven’t lasted very long, ranging in most cases just 15 to 40 minutes. But during that time frame, many “shooting stars” have been seen.
Where and When to Look
The current outlook is for Earth to make its closest approach to this dust trail at around 11:50 p.m. Eastern Time on Thursday night, November 2st, 2019. There is a bit of uncertainty as to just how close Earth will come to the center of the trail, making an exact estimate of the meteor rate difficult. For a period of perhaps as much as 20 minutes before to 20 minutes after that 11:50 p.m. time, a single observer might see meteors falling anywhere from 1 to as many as 8 per minute! Chose as dark a viewing site as possible, far from any bright lights along with a wide-open view of the sky.
Meteor activity could conceivably be all but over by 12:10 a.m. It will be that quick. If nature is in a show-off mood, you might end up seeing dozens of shooting stars to wish on. If the display falls short, and you don’t try too desperately hard, you might still come away seeing one or two really beautiful meteors.
Those who live in the Eastern Time Zone will have the best chance to catch this meteor activity. The region of the sky where the meteors will be darting from will be about a quarter of the way up from the horizon.
Farther west, for the Central and Mountain Time Zones, the time of maximum activity will come at 10:50 p.m. and 9:50 p.m. respectively. But unfortunately, as you progress westward, the emanation point of the meteors will be getting lower in the sky and in fact, for the Rocky Mountain and Southwest Desert states it will be sitting right on the horizon and likely significantly lowering the number of meteors that might otherwise be seen.
Unfortunately, for those living in the Pacific Time Zone, where the meteors emanation point will be below the horizon, little or nothing of the display may be seen, although if they are lucky, some observers may be able to spot an unusually beautiful type of meteor called an “Earthgrazer” around 8:50 p.m. when the shower is at its maximum. Earthgrazers are long, bright shooting stars that streak overhead from just below the horizon. They often display colorful halos and long-lasting trails. Earthgrazers are so distinctive because they follow a path nearly parallel to our atmosphere.
Amidst all the uncertainties, one thing is for sure: If you don’t go out and look, you’re sure not to see any!
Good luck and hope for clear skies!
Joe Rao is an esteemed astronomer who writes for Space.com, Sky & Telescope, and Natural History Magazine. Mr. Rao is a regular contributor to the Farmers' Almanac and serves as an associate lecturer for the Hayden Planetarium in New York City.