Comet ISON
 

Anyone following this ball of ice? God I hope it survives perihelion today, so that I can finally see another comet that could rival Halley's Comet, Hale-Bopp, and Hyukatake. Last couple of bright comets seemed like they were only visible in the Southern Hemisphere (which has a way better sky than we northerners get anyways :( ). I still remember Hale-Boop being visible with a huge tail that that could be seen stepping out in the backyard even at 11PM after it swung around the Sun, and by 2-3 AM after driving out of town the tail took up half my field of vision. Can't wait to see if NASA has any more info on it when they do thier ISON Google hangout at 1PM Eastern.

WATCH LIVE THURSDAY: Comet ISON Buzzes the Sun - NASA Webcast @ 1 p.m. ET | Space.com

I managed to catch Pan-STARRS last year, which was cool but nowhere near as impressive to see as Halley's Comet, Hale-Bopp, and Hyukatake were.

It's on live now, and is still intact. I think it gets to perihelion in the next hour and a half or so.

Crap, it may be losing brightness, which would indicate its rocky core has come apart. :(

Perihelion in about 15 minutes.

Thanks.going there now!

That site has too many commercials/ads and has my PC locked up. Tried to see it outside but the sun is too drn bright!

Here too: NASA Television | NASA

Nothing on the SDO field. :(

You'd have no chance of seeing the comet outside right now. If it somehow survives the swing around the Sun there is an outside chance that it could be bright enough to see in the day like the great comet of 1680, as it is going extremely close to the Sun and will have tons of its water evaporated into a tail.

Looks like the comet has broken up from the image taken 45 minutes ago

RIP Comet ISON :(

Crap, I was looking forward to it all year

Two well-defined tails: one thought to be dust from the core, one thought to be the evaporating gas. The same kind of heavy dust tail they saw on Shoemaker-Levy 9 when it slammed into Jupiter in 1994.

Hope they show it on the news tonight. I've looked at the sun during eclipses and it was never this bright.

Well, crap. Hopefully something like this one comes in and survives within the next 20-30 years. Still 48 years until Halley's Comet comes.

Wow, according to the latest photo published by SOHO there may still be a solid core intact.

ISON Update for 22:00 UTC Nov. 28.
[UPDATE 2 (Nov. 29 at 02:30 UTC): This beastie continues to surprise. This SOHO image, from 00:18 UTC on Nov. 29, sure looks like something survived intact. At this point all I can say is the same thing I've been saying all along: predicting comets is like predicting cats. Good luck with that. For those keeping score at home, it got bright, then it faded, then it got all smeared out, then it came around the Sun smeared out, and then it seemed to get its act together again. At this point, I refuse to make any further conclusions about this comet; it seems eager to confuse. I've been hearing from comet specialists who are just as baffled... which is fantastic! If we knew what was going on, there'd be nothing more to learn.]

For anyone who hasn't heard the 'predicting cats' saying above, it comes from the saying

Comets are like cats. They both have tails and they just do what they want.

I missed Hale-Bop, so I am still waiting for my first good comet.

I really hope I can live to see one as impressive as Hale-Bopp again. Not sure I can make the 48 years to Halley's Comet's reappearance, but that was spectacular the last time it came by in 1986. I'm still jealous of the Southern Hemisphere getting to see Lovejoy in 2011 and people born in the 50s who got to see Ikeya-Seki in 1965.

Was hale bopp the one in the late 90s? I remember that one was really bright and I could even see it during the day. Wasn't that also when that cult did the mass suicide?

Yeah, the Heavens-Gate Cult preached that they had to catch a spaceship behind Hale-Bopp. I think that was 1997, while Hyukatake was 1996 and was also incredible.

Wow, this is so cool (not my blog post).

Schrödinger's Comet
Submitted by Karl Battams on Thu, 11/28/2013 - 20:35

I'll just say this upfront right now: whatever you read in the following blog post, please feel free to assume it is completely incorrect and the truth is actually quite contrary to what I'm saying. It has been - and continues to be - one of those days.

So this will be a relatively brief blog post because we're up to our necks in media inquiries and attempting to do real science to figure out the mystery that is comet ISON, and Matthew and I are basically the only ones that have abandoned our loved ones on this US national Holiday and continued to work. Here's what we know so far:

After impressing us yesterday, comet ISON faded dramatically overnight, and left us with a comet with no apparent nucleus in the SOHO/LASCO C2 images. As the comet plunged through the solar atmosphere, and failed to put on a show in the SDO images, we understandably concluded that ISON had succumbed to its passage and died a fiery death. Except it didn't. Well, maybe...

After perihelion, a very faint smudge of dust appeared in the the LASCO C2 images along ISON's orbit. This surprised us a little, but we have seen puffs of dust from Sungrazer tails, so it didn't surprise us enormously and didn't change our diagnosis. We watched and waited for that dust trail to fade away. Except it didn't.

Now, in the latest LASCO C3 images, we are seeing something beginning to gradually brighten up again. One could almost be forgiven for thinking that there's a comet in the images!

Matthew and I are ripping our hair out right now as we know that so many people in the public, the media and in science teams want to know what's happened. We'd love to know that too! Right now, here's our working hypothesis:

As comet ISON plunged towards to the Sun, it began to fall apart, losing not giant fragments but at least a lot of reasonably sized chunks. There's evidence of very large dust in the form of that long thin tail we saw in the LASCO C2 images. Then, as ISON plunged through the corona, it continued to fall apart and vaporize, and lost its coma and tail completely just like Lovejoy did in 2011. (We have our theories as to why it didn't show up in the SDO images but that's not our story to tell - the SDO team will do that.) Then, what emerged from the Sun was a small but perhaps somewhat coherent nucleus, that has resumed emitting dust and gas for at least the time being. In essence, the tail is growing back, as Lovejoy's did.

So while our theory certainly has holes, right now it does appear that a least some small fraction of ISON has remained in one piece and is actively releasing material. We have no idea how big this nucleus is, if there is indeed one. If there is a nucleus, it is still too soon to tell how long it will survive. If it does survive for more than a few days, it is too soon to tell if the comet will be visible in the night sky. If it is visible in the night sky, it is too soon to say how bright it will be...

I think you get the picture, yes?

We have a whole new set of unknowns, and this ridiculous, crazy, dynamic and unpredictable object continues to amaze, astound and confuse us to no end. We ask that you please be patient with us for a couple of days as we analyze the data and try to work out what is happening. We realize that everyone now wants to know if it will be visible in the night sky, and how bright it might be. We really hate speculating right now but if someone were to force us into an answer, we would reluctantly say that at least some faint tail remnant should be visible in the coming week or so. But this is highly speculative so please don't take this too seriously just yet. We will absolutely post updated info here as soon as we're more confident, and I will of course continue blogging when I can in the meantime. Just be patient on this and the truth will unfold in time!

And I just want to end on this note: not long after comet ISON was discovered, it began to raise questions. Throughout this year, as many of you who have followed closely will appreciate, it has continued to confuse and surprise us. For the past few weeks, it has been particularly enigmatic and dynamic, in addition to being visually spectacular. This morning we thought it was dying, and hope was lost as it faded from sight. But like an icy phoenix, it has risen from the solar corona and - for a time at least - shines once more. This has unquestionably been the most extraordinary comet that Matthew and I, and likely many other astronomers, have ever witnessed. The universe is an amazing place and it has just amazed us again. This story isn't over yet, so don't stray too far from your computer for the next couple of days!

It looks like ISON is winding down now. It has dimmed pretty significantly on the SOHO image since about 18:00 UTC time, as you can see in the video below:

SOHO Movie Player

Last update about 5 hours ago had ISON at a magnitude +5 with a dust tail, so it sounds like there is basically zero chance of it being naked eye visible. +5 would already be hard to see in the pre-dawn sky unless you're away from a city and with no development to the southeast. And no way it's even +5 in a few days once it has moved farther away from the Sun. It was a +3 only 9 hours ago, so it's fading fast. Even though it'll never be the -13 magnitude comet it was projected to be last year, it completely defied all predictions and thus should have some very interesting consequences in understanding our solar system. Everyone studying it has said it's the craziest comet ever observed.

I don't know much about space stuff, but I find this fascinating.

It has faded bigtime now on the 16:06 shot from SOHO.

http://198.118.248.97/data/realtime/c3/1024/latest.html

It's in the top-right, about halfway between the vertical and the big black line from the arm holding that disc in front of the Sun. Apparently the motion and quick dimming is pretty in line with it being debris from a destroyed comet as opposed to a small nucleus surviving perihelion. Considering that latest image is more than 2 hours old, I wonder if the comet's remains will even be visible by the next published photo.