Starship Asterisk*

by **JohnD** » Tue Nov 13, 2007 1:22 pm

FieryIce wrote:... His tail swept down a third of the stars of heaven and threw
them to the earth.....

Ohhh I just couldn't resist.

I had to Google that - Revelations 12:1-17
see: http://www.westminsterstpauls.ca/church ... ?SER_ID=72
Or of course consult your Bible.

Fierce stuff!
But a reasonable description of a mighty comet!

John

by **JohnD** » Thu Nov 08, 2007 6:41 pm

Look, I'm not claimimg anything for myself, but this is getting more and more significant!

by **orin stepanek** » Thu Nov 08, 2007 2:11 pm

JohnD wrote:And a star rising in the .......................
Actually, I don't know where Comet Holmes rises.

John the Church of England
(if I'm anything, but I'm not a Baptist)

Probably in the East as does most objects due to rotation of the Earth.
Orin

by **FieryIce** » Thu Nov 08, 2007 2:09 pm

... His tail swept down a third of the stars of heaven and threw
them to the earth.....

Ohhh I just couldn't resist.

by **craterchains** » Thu Nov 08, 2007 9:58 am

, , , and upon this "rock" I will build my church.

Sorry, just couldn't help myself.

by **JohnD** » Wed Nov 07, 2007 10:30 pm

And a star rising in the .......................
Actually, I don't know where Comet Holmes rises.

John the Church of England
(if I'm anything, but I'm not a Baptist)

by **orin stepanek** » Wed Nov 07, 2007 3:44 pm

JohnD wrote:
orin stepanek wrote:The tail has come! http://antwrp.gsfc.nasa.gov/apod/ap071105.html; Yah!
Orin
YeeeeeeeeeeeeHA!
Am I a prophet or am I a prophet?

John

Oh my; now we have God and a Prophet!

Just joking JohnD
Orin

by **JohnD** » Tue Nov 06, 2007 10:00 pm

orin stepanek wrote:The tail has come! :P http://antwrp.gsfc.nasa.gov/apod/ap071105.html; Yah!
Orin

YeeeeeeeeeeeeHA!
Am I a prophet or am I a prophet?

John

by **ta152h0** » Tue Nov 06, 2007 7:47 pm

By activity I mean the difference between a rock serenely cruising thru space mostly unnoticed and a rock getting pulverised by other rocks while doing so, becoming noticed by us. Becoming noticed by us is the key concept here. Pass the beer

As our " eyes ' get better, this concept of " serenely cruising thru space unnoticed " becomes harder to do.

by **Chris Peterson** » Mon Nov 05, 2007 6:32 pm

ta152h0 wrote:Is it not the case that the only mechanisms for cometary activity is sunlight light pressure and heat, collisions and close encounters with planets ?

Depends what you mean by "activity". Certainly, all those things can influence the appearance of a comet. But by far the dominant mechanism for what is usually called activity is heat. First you need to boil off gas, which carries dust with it. Then the solar wind can sweep it away, producing the characteristic tail. Collisions and close encounters with planets may expose interior surfaces, allowing volatiles to escape easier. But I wouldn't say that of themselves they produce activity.

by **ta152h0** » Mon Nov 05, 2007 6:15 pm

Is it not the case that the only mechanisms for cometary activity is sunlight light pressure and heat, collisions and close encounters with planets ?

by **Chris Peterson** » Mon Nov 05, 2007 6:06 pm

ta152h0 wrote:yahoooooooo the tail has a comet attached. I just found the pictorial of the orbit and it is way above the ecliptic. Assuming a lot of dust in the ecliptic plane, does that imply increased sunlight above ( or below ) the ecliptic ? It seems like this comet is reacting quite strongly despite the great distance from the sun.

No, the amount of solar energy lost to dust absorption in the ecliptic plane is really tiny. Comets outside the orbit of Mars can produce dust trails, as long at the comet is active enough to be producing dust, as Holmes is. It probably had a tail within hours of its outburst, but it took a week before it stretched out enough to finally show since it's almost directly behind the comet.

by **ta152h0** » Mon Nov 05, 2007 5:55 pm

yahoooooooo the tail has a comet attached. I just found the pictorial of the orbit and it is way above the ecliptic. Assuming a lot of dust in the ecliptic plane, does that imply increased sunlight above ( or below ) the ecliptic ? It seems like this comet is reacting quite strongly despite the great distance from the sun.

by **orin stepanek** » Mon Nov 05, 2007 1:29 pm

The tail has come!

http://antwrp.gsfc.nasa.gov/apod/ap071105.html; Yah!
Orin

by **NoelC** » Mon Nov 05, 2007 3:48 am

It has a plasma tail. A number of amateurs have imaged it, including myself and my friend.

An amateur astroimager in the UK has captured a closeup of the head with a curving dark line, which looks for all the world like obscuring dust, across it. This could be a clue to what happened to cause it to brighten.

http://ukastroimaging.co.uk/forums/inde ... ic=33279.0

-Noel

by **ta152h0** » Sat Nov 03, 2007 7:55 pm

Doesn't take much of a collision to produce large clouds of material. Remember what a little bitty piece of copper did to tempel 1 ? I remember well the oooohhs and ahhhhhhs and awmygods...........I have read many comments that the chances of getting hit are very small and the jury is still out on what happened. Maybe a UFO gas tank blew up............................naw, sorry guys. back to serious stuff, pass the beer

by **orin stepanek** » Sat Nov 03, 2007 4:09 pm

This comet is interesting in several ways: We can't see the tail; It flared up suddenly: and it resides in the asteroid belt. Makes you wonder if there is a strong similarity between comets and asteroids. Maybe comets have more ice because: generally, they reside so far away and haven't had the solar encounters devoid them of their water content yet!

Orin

by **Chris Peterson** » Sat Nov 03, 2007 2:33 pm

JohnD wrote:Many comets have two tails, one dust, the other plasma (?- electrically charged, anyway) that curves. If we can't see that curving tail, then Holmes doesn't have one. What does this tell us about Holmes?

Both a dust tail and ion tail are starting to show up in images. Presumably, the comet's distance from the Sun slowed their formation, and the very large and fast growing coma hid them from us until they grew long enough to finally become visible around the comet's edge.

by **craterchains** » Sat Nov 03, 2007 11:04 am

That something "dusted" it off? 8)

by **JohnD** » Sat Nov 03, 2007 9:02 am

Today's APOD (3/11/7) makes the point that the comet is receding, tail first, and happens to have the tail pointing directly away from Earth.

Many comets have two tails, one dust, the other plasma (?- electrically charged, anyway) that curves. If we can't see that curving tail, then Holmes doesn't have one. What does this tell us about Holmes?

JOhn

by **MalcolmP** » Wed Oct 31, 2007 6:44 pm

Chris Peterson wrote:It is precisely because it carries the orbital velocity of the comet that the coma is spherical. If you take the center of the nucleus as your frame of reference, the particles move away from it in all directions but at a constant speed...

Thanks, brill. explantion yes I see.
/offers Chris a pint of homebrew beer

by **orin stepanek** » Wed Oct 31, 2007 12:33 pm

craterchains wrote:, , , , , , but, what made it get brighter?

OOOOO000000OOOOOO00OO0o0oo00

Just maybe; that's one of the things we could learn.

Orin

by **craterchains** » Wed Oct 31, 2007 5:18 am

, , , , , , but, what made it get brighter?

OOOOO000000OOOOOO00OO0o0oo00

by **orin stepanek** » Wed Oct 31, 2007 1:11 am

I wish a probe could be sent there. It would make a most interesting study. A lot could be learned from this comet.

Orin

by **ta152h0** » Wed Oct 31, 2007 1:05 am

wonder if cASSINI can image this phenomenal object ?

Starship Asterisk*

Comet Holmes in Outburst (APOD 26 Oct 2007)

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Expand view Topic review: Comet Holmes in Outburst (APOD 26 Oct 2007)

by activity i mean

Re: cometary activity

cometary activity

Re: tail

tail

Plasma Tail Exists

comet collision ?

wonder if cASSINI