Comet Returns After 37,000 Years

BBC ^ | 2-19-2003

[LibWhacker]

And its only "invisible" because we can't see it (without instruments) in the glare of the sun.

[lawdude]

"The comet is putting on a spectacular show Calculations show it has passed through the inner Solar System once before but this was 37, 000 years ago. "

Ask Helen Thomas what it was like the first time around!

[Shermy]

Strange Clouds

From NASA, FYI. Interesting.

[Political Junkie Too]

There is a purple spot just behind the comet. No... Never mind. That's a fingerprint on my monitor.

A FLO, huh? (Finger-Like Object).

-PJ

[Cuttnhorse]

Any news about when and where it is visible...inquiring minds in South America want to know.

[meadsjn]

...what's the horizontal straight line poking out from behind the comet's head...edge-view of a flying saucer?

My guess is something like the rings of Saturn. The pics are awesome, though.

[Centurion2000]

To put a coma out the size of jupiter means that the nucleus of this thing must be huge .... on the order of a small moon.

This almost reminds me of the scenarion from Moonfall.

Either way it could provide an awesome light show if it hit the moon ... and maybe wake people up that we are in the cosmic equivalent of a shooting gallery.

As far as pushing Earth from its orbit it would have to do a close fly-by maybe even inside the Roche limit.

[6ppc]

Actually it's Pournelle and Niven

[HighWheeler]

"On Nov. 6, 2002 the NEAT-team found a new comet near the border of the constellations Taurus/Orion. Comet C/2002 V1 (NEAT) was of magnitude 16 and showed a 0.4' coma and a tail of 0.4' length towards p.a. 250°. According to the current elements this comet will come as close as 0.1 AU to the sun on Feb. 18, 2003 (IAUC 8010/11). However, it is very uncertain whether this comet will survive this close encounter, because its absolute magnitude of about 11.5m is well below a "survivance" limit defined by an empiric analysis of John Bortle. Nevertheless, assuming the case of an average brightness evolution it could attain a maximum brightness of 1-2m at perihelion, displaying a 5° tail. However, during those days the elongation will only be 6°. In this scenario it would be brighter than 10m from the end of January to the beginning of March, brighter than 6m from about Feb. 12 to 23. For mid-European observers the comet would get out of view around Feb. 10, if a solar depression of only 12° is assumed. But again, this scenario will only come true if the brightness evolution will be average. Even in this very optimistic scenario the comet will remain a telescopic object for mid-Europeans."

[RightWhale]

The gaseous coma had a diameter of 148,000 miles in January. The actual solid body is not large, a few miles.

[e_engineer]

This is obviously someone measuring the apparent size of the comet in the SOHO images, and failing to account for the fact that the nucleus is surrounded by a coma (temporary atmosphere)due to the extremely rapid sublimation as it approaches the Sun.

The actual diameter of the nucleus is probably less than 100 km, but is hidden by the coma.

Here is a quote from a APOD (Astronomy Pic of the day) glossary: coma: A spherical cloud of material surrounding the head of a comet. This material is mostly gas that the Sun has caused to boil off the comet's icy nucleus. This gas shines both by reflected sunlight and light emitted by excited molecules. A cometary coma can extend up to a million miles from the nucleus.

[JoeSixPack1]

Ok trekkies, it's a mini-dyson's sphere in motion!

[HighWheeler]

Here is a gif of the comet's "tail disconnection event":

[e_engineer]

One theory of the origins of water on the terrestrial planets is delivery by comets. IIRC the idea is that water could not have existed this close to the sun in the primordial disk from which the planets formed. (it would sublimate and be blown away by the solar wind) In addition, the heat of formation (the kinetic energy of all of Earth's mass as it falls together) would boil off any water that fell in during the formation period.

Here is a link from a google search on "Origin of Oceans": here

[LibWhacker]

Here's a nice little series (I'm series!). Grab your scroll bar and pull it up rather rapidly and you can watch as the comet makes its way around the sun to begin its journey on the outbound leg. Gee whiz, last time this baby made an appearance, Neanderthal had just died off. Wonder what Earth will be like next time it comes this way?

[Pilsner]

we're DOOMED

I guess this would be a good time to short 20 years t-bills.

[blam]

Neat, thanks. The Neanderthals were still around 28,000 years ago.

[LibWhacker]

Oh, they were? My bad. I thought they died off 40,000 years ago.

[blam]

"Oh, they were? My bad. I thought they died off 40,000 years ago."

I know more about this than I do comets, lol. (Although I am a catastrophist)

Neanderthal-Cro-Magnon Hybrid?

[Doc On The Bay]

GREAT book;----&, oh, I HOPE NOT!

Doc