C/2012 S1 (ison) Could Be The Brightest Comet Ever Seen By Mankind

[cheese]

The media jumped on the 'Ison is dead' bandwagon too quickly, and may end up looking very foolish indeed. To be fair, even astronomers and physicists alike said the comet had likely been destroyed, but now, they're not so sure. 

Edited November 29, 2013 by cheese

[Devonian]

I think the BBC, and the rest of the quality media, have reported what is being said. They're the messenger. The message is, as ever, that comets are unpredictable.

[joggs]

So what is going on? Lol

[lorenzo]

SOHO scientists announced ISON had vaporized at perihelion.

Then ISON appeared out of nowhere at around 1145 on the C3 Solar observer.

Who knows !!! Looks like it has survived to me.

[Gray-Wolf]

 

Well Isons still hanging in there even if the 'realtime imagery' was a dud last evening. I suppose trying to see such a small object in such a bright environment was too much of an ask? Once Ison got to a certain point the heat instantly boiled away any gasses and gravity/electromagnetic fields did for the solids so we all sat and saw nowt!

 

Once far enough away the gasses still survive and we see the coma build up again and then the tail. The question has to be how much of the head made it through? By the end of the day we should again see Ison with a decent tail again (I hope!).

[Coast]

Back from dead? Hope revives for 'comet of the century Ison' after encounter with Sun

 

 

Astronomers tracking the “comet of the century†believed it had flown too close to the Sun and had broken up, but hopes have now been reignited that part of it may have survived its close encounter. Comet Ison was due to pass within 730,000 miles of the Sun’s surface shortly after 6.30pm. It was initially declared dead after it did not re-emerge from behind the sun with the expected brightness. “We don’t think it survived because we don’t see any new dust,†Nasa’s Solar Dynamics Laboratory said.

 

It was hoped that Comet Ison would provide a spectacular sight in the sky in early December. If enough of it had survived, it promised to be one of the brightest seen this century. At around 1.2 miles (2km) across, it was thought it could be just big enough to avoid being melted away by the Sun or turned to dust. Even at a greatly reduced size it was hoped it could produce a glorious long tail, visible to the naked eye from the UK from 1 December onwards.

 

Images from Nasa spacecraft showed the comet approaching for its slingshot around the sun today - but nothing emerging from the other side, suggesting it had been burned up on its journey. However, recent pictures have suggested a brightening of what could be a small part of the comet, according to the BBC. This could continue brightening, or could simply fizzle out. As the comet brushed past the Sun, it would have encountered temperatures of more than 2,700C (4,892F), enough to vaporise rock.

 

US Navy solar researcher Karl Battams said: "Ison probably hasn't survived this journey." Phil Plait, an astronomer who runs the Bad Astronomy blog, agreed, saying: "I don't think the comet made it." But it would not be all bad news if the rock broke into pieces, he said, because astronomers might be able to study them and learn more about comets. Nasa solar physicist Alex Young said it would take a few hours to confirm Ison's demise, but things were not looking good. He said the comet had been expected to appear in images from the Solar Dynamics Observatory spacecraft at around 5pm British time, but almost four hours later there was "no sign of it whatsoever". He added: "Maybe over the last couple of days it's been breaking up. The nucleus could have been gone a day or so ago."

 

Astronomer Dr Dan Brown, from Nottingham Trent University, said earlier: "Astronomers around the world are hoping that Ison will become an amazing sight for the naked eye in the first half of December. They are keeping a close eye on it, using some of their solar observatories in space. "People at home can also capture a glimpse if it survives. Just look out for it half an hour before sunrise from December 1 onwards. It will be visible low in the east-south-eastern horizon. "This close encounter with the sun also offers a unique opportunity for astronomers to analyse the composition of a comet. Comets are icy, dusty snowballs - the remains from the formation of our solar system 4.5 billion years ago. "The long tail containing the material frozen in the comet and released through the heat of the sun offers astronomers the chance to identify different elements."

 

http://www.independent.co.uk/news/science/comet-ison-can-comet-of-the-century-survive-close-encounter-with-the-sun-8969061.html

[DAVID SNOW]

I wonder if ISON(whatever still remains) is still on the same orbit as calculated by nasa many months ago or are the space boffins at nasa now franticly re calculating its new orbit?

[Jax]

I wonder if ISON(whatever still remains) is still on the same orbit as calculated by nasa many months ago or are the space boffins at nasa now franticly re calculating its new orbit?

I did think that this morning when I saw the news some had survived, the previous calulations based on more mass of the object and how much of the stress it has taken recently changed all that now?

[Eskimo]

Well it's now obvious ISON did survive, however probably half its weight!

[Gray-Wolf]

So maybe the 'influence' the sun has over this small fragment is different from the one they used in the original calcs? Will the Sun now 'bend' the orbit more or will the orbit not be 'bent as much? .More of a 'bend' might mean more fragments for our meteor shower in jan? 

[SomeLikeItHot]

So maybe the 'influence' the sun has over this small fragment is different from the one they used in the original calcs? Will the Sun now 'bend' the orbit more or will the orbit not be 'bent as much? .More of a 'bend' might mean more fragments for our meteor shower in jan? 

 

Mass is irrelevant to orbit generally (gravitational force and inertia cancel), however if there is a break up and the fragments are moving apart each could have a differnet trajectory. Not hard to recaclulate though if they have a fix on its current position and velocity.

[Bobby]

Even the grizzled professional scientists and comet experts are baffled by ISON it seems, a good write up here from the NASA team

 

http://www.isoncampaign.org/karl/schroedingers-comet

 

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!

...

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.

 

Matthew Knight and I have looked at literally a couple of thousand sungrazing comets. We've NEVER seen one behave like #ISON. Astounding!

Something obviously has survived by nobody knows what. Small fragments and dust, larger fragments, a smaller battered but still remaining nucleus?

 

If ISON has survived to some significant extent this will be the biggest comeback since Lazarus!

Edited November 29, 2013 by Bobby

[Bobby]

 

ISON has a very different look to it now. There is no long tail as before, looks more like a cloud. Looks odd for a comet to me, maybe what we're seeing is a cloud of debris and smallish fragments being blown and heated by the Sun? If there was a nucleus actively releasing dust and gas you'd think it would leave behind a tail...

 

Oort cloud

 

[Buriedundersnow]

20131129_1337_c3_1024.jpg

 

ISON has a very different look to it now. There is no long tail as before, looks more like a cloud. Looks odd for a comet to me, maybe what we're seeing is a cloud of debris and smallish fragments being blown and heated by the Sun? If there was a nucleus actively releasing dust and gas you'd think it would leave behind a tail...

 

Oort cloud

 

 

theres no long tail like before because you were watching it from behind before going into the sun so you could see the streak it left behind now it is coming towards us the tail is pointing in the same direction (being blown away from the sun) so in that image you are looking at the comet through the tail.

[Gray-Wolf]

Ison had also travelled the millions of km that the pre-contact tail stretched out for. Now I imagine it has to start from scratch again ? first it has to be far enough from the sun for the corona to re-form and then start to build the trail as it goes ( which is then blown by the solar wind?). The dust tail shows us it 'path' and the ion tail is points away from the sun?

[Boro Snow]

Based on a few more hours of data, comet #ISON appears to be... well, behaving like a comet,,, a tweet by Karl Battams

[misha]

While I'm disappointed that Comet Ison may not provide the celestial fireworks we had hoped for it's nice to see the Universe throwing us a curveball yet again. Fascinating to follow and who knows what will happen next!

[Coast]

All is saved.... :unsure:

Comet Ison appears to survive close encounter with the sun

 

Solar visit threatened to vaporise the comet but the remnant may be visible from Earth in December

 

 

Travelling at more than 200 miles per second, Ison passed 730,000 miles above the sun's 6,000C surface on Thursday evening. This would have heated the comet to almost 3,000°C, enough to vaporise rock as well as ice.

 

"It would be an absolutely hellish environment, there's never been a better time to use the words 'snowball's chance in hell'," said Tom Kerss, astronomer at the Royal Observatory in Greenwich, south-east London

 

http://www.theguardian.com/science/2013/nov/29/comet-ison-survive-encounter-sun-earth

 

[Buriedundersnow]

While I'm disappointed that Comet Ison may not provide the celestial fireworks we had hoped for it's nice to see the Universe throwing us a curveball yet again. Fascinating to follow and who knows what will happen next!

 

it will still be pretty bright In the sky look how bright it is just now that wont fade by the time it passes us don't lose faith in it just yet you will see it big and bright as it passes

[Mokidugway]

Comet Igone not gone !!...

[Bobby]

This STEREO Behind COR2 video is interesting, doesn't look too healthy to me on this view as it leaves the sun

 

 

The NASA ISON team:

 

One thing we can be certain of is that ISON's nucleus (if there is one) will be significantly smaller now. Lot of mass will have been lost! 

Seems maybe something is still producing dust but whether it's a coherent nucleus or a dust ball, we dont know

Edited November 29, 2013 by Bobby

[Buriedundersnow]

This STEREO Behind COR2 video is interesting, doesn't look too healthy to me on this view as it leaves the sun

 

 

The NASA ISON team:

 

One thing we can be certain of is that ISON's nucleus (if there is one) will be significantly smaller now. Lot of mass will have been lost! 

Seems maybe something is still producing dust but whether it's a coherent nucleus or a dust ball, we dont know

 

there is nothing wrong with that video all you are seeing in that as it leaves the sun is the tail ripping round and changing direction as the sun is on the other side of it now

Edited November 29, 2013 by Buriedundersnow

[Boro Snow]

This STEREO Behind COR2 video is interesting, doesn't look too healthy to me on this view as it leaves the sun

 

 

The NASA ISON team:

 

One thing we can be certain of is that ISON's nucleus (if there is one) will be significantly smaller now. Lot of mass will have been lost! 

Seems maybe something is still producing dust but whether it's a coherent nucleus or a dust ball, we dont know

Check this video out it shows it a little better what buriedundersnow is talking about

 

http://www.youtube.com/watch?v=qdnAfrMFQkc

[Buriedundersnow]

Check this video out it shows it a little better what buriedundersnow is talking about

 

http://www.youtube.com/watch?v=qdnAfrMFQkc

 

nice find shows it nice and bold and bright.

 

it is still there we will still see it in the skies as it passes weather permitting of course.

 

main question mark is trajectory as we haven't really heard much on that which is a little worrying.

[Buriedundersnow]

what people need to remember when viewing the sattelite images is just because it isn't bright doesn't mean it is dead or on its way out you have to look at all images to get the real picture as different sattelites operate in different light spectrums so it will look duller in some and brighter than in others just depending on what light the sattelite is picking up.

 

don't get caught out people just because you see one image or video and it doesn't look that good.

Edited November 29, 2013 by Buriedundersnow