The Brightest Comet in the Past 30 Years
Sunday, January 21 2007 @ 11:30 am EST
Contributed by: bobmoody
AOAS' own comet expert, Mike Holloway, has been following the latest visitor to the inner solar system known as Comet C/2006 P1 McNaught over the past several months. It is only rarely that we are treated to a comet which becomes a real spectacle as it makes its closest approach to the Sun, and Comet McNaught is certainly now a spectacle. The last comet that was this spectacular and sported several similar aspects to McNaught was Comet West in March 1976.
While we won't be able to see this comet's grand finale as it has now switched to the southern skies, there are plenty of experienced amateur astronomers in the southern hemisphere. Here are the images from Mike Holloway's newly restored Holloway Comet Observatory as McNaught came into prominence for the northern observers, and also the work of Australian astronomer Vello Tabur detailing this comet's unexpectedly exciting apparition for southern observers.
|Mike Holloway imaged the bright comet C/2006 P1 McNaught near the horizon north of Van Buren on January 8, 2007. It had only recently been characterized as the brightest comet in 30 years. |
It may only happen every 30 to 50 years. Either a new or a long-period (200+ years between apparitions) comet returns to the inner solar system and brightens to a level so bright that they can sometimes be seen even in broad daylight! New comet C/2006 P1 McNaught has become the first comet to reach this level of brightness in at least the past 30 years.
Our own AOAS comet photographer has been watching and imaging McNaught for the past few months, and occasionally sending me an email expressing his suspicions that this one would be especially bright. It was my own fault for not listening to Mike before the first of 2007, but I'm now a true believer.
On January 11, I was at the Git-R-Dun laundromat on Logtown Hill in Van buren, AR, when I started watching for the comet as the Sun set below the horizon that evening. Without any trouble at all, I could see it in considerably bright twilight, even the tail stretching up and curving to the right of the nucleus. I asked everyone in the laundry at the time to come and see, and all but two were also able to see it without optical aid. That's a fairly profound thing to someone like myself who has seen a number of comets in the last 22 years, but I've never seen one anywhere close to that bright ever before. My only disappointment was the knowledge that when the comet was to be at its brightest a few days later, it would by then be below the horizon for all northern hemisphere observers making that sighting my only view of the comet.
For northern hemisphere observers and comet chasers, the show from comet C/2006 P1 McNaught is over. Our luck just didn't pan out this time. It happened similarly for southern hemisphere observers for comets Hyakutake and Hale-Bopp in 1996 and 1997 respectively. Then it was we who had the show of a lifetime, while our southern counterparts only saw the later remnants of those two comets. All of us who were able to see those comets will never forget their appearance, just as southern astronomers will likely never forget this appearance of Comet McNaught.
|Australian astronomer Vello Tabur imaged comet McNaught on January 19th with an impressive tail sweeping away to the north of the comet's nucleus. |
Click read more for the BEST images and for links to images of other exceptionally bright comets in the (relatively) recent past.
The wonderfully fan-shaped tail of McNaught seen sweeping up and right from the "head" is due to the comet's passage close to the Sun. Just as Earth passes at our closest point to the Sun and hence reaches its highest velocity of its orbit in January each year, so McNaught also is travelling at its fastest speed while passing closest to the Sun. The outward flowing energy of the solar wind causes the comet's tail to be pushed away from the Sun no matter where it is in its orbit in relation to the Sun.
In fact, as McNaught begins its outward leg of this apparition, the tail will be seen to lead the way, trailing the head behind it in the coming days and weeks. The comet's position close to the Sun, the solar wind, the speed of the comet as it whips around the Sun, all add up to produce the unusually wide-swept tail. What a sight it must be for anyone in Australia, South America and Africa as long as this comet lingers in the evening twilight night after night.
|Vello Tabur, an Australian astronomer, shot this image from down under on January 20th. Such an impressive fanning-out of a comet's tail is rare, with conditions and positions of the comet in its orbit relative to Earth needing to be "just right" to cause the comet to be seen this way.|
View Vello Tabur's website which includes numerous interesting articles and images.
Also see the complete set of images used for this aticle through this link.
Holloway Comet Observatory Struck by Lightning
When This Comet Dies
Speculations on the Comet's Last Stand
And MANY More in the Lunar & Planetary Topic Section