NASA have confirmed Comet Ison is now dead.
On Tuesday 3rd December NASA have confirmed that Comet Ison, the Comet that so many people around the world hoped would bring a spectacular light show to our skies, is definitely dead. All that remains is a huge cloud of debris with no nucleus.
I first read about Ison about a year ago when the exact course the Comet would take was unknown. I was excited by the prospect of another Comet coming into view, I remember how amazed I was at the sight of Hale Bopp back in the 90's, visible without a telescope even during the day for weeks, and Ison was expected to be even brighter, with many experts saying that it could be as bright as the Moon. I couldn't wait!
As Ison came closer, experts began to say that Ison may not be the event they had predicted, they said it was not as bright as they thought it would be and I was a little deflated to hear this, but then a few days later Ison brightened as it came closer to the Sun and heated up. The heat caused gasses and vapour to spray out from Ison for miles, and as the Sun's light hit these emissions it made Ison appear much brighter. This of course is my own not scientific interpretation of how Ison became brighter. Experts told us that sightings of Ison without telescopes and the possibility of viewing Ison even during daylight were again possible... As long as Ison could make it's pass around the Sun without being destroyed.
When last week Ison finally had it's closest encounter with the Sun, no technology could see what was happening because it was on the other side of the Sun. The wait was on to see if Ison would appear where it was expected to appear having made it's pass of the Sun. The news was bad, on Thursday 28th November NASA told the world's press that Ison had completely disintegrated. I thought that was the end of it, pushed my disappointment to one side and got on with my day. But then, a few hours later, just after the world's media had published the news that Comet Ison was dead, NASA announced that Ison was once again in view and was at least in part, in-tact.
I don't think we could have expected any astonishing views of Ison with the naked eye after it's adventure around a the far side of the Sun, after all, scientists were pretty clear that although Ison had been seen again, it was by no means as bright or large as it was on it's approach. But I was still sad to hear on Tuesday that NASA have once again confirmed that Ison is now dead. All that remains is a see-through mass of debris with no nucleus.
One thing I have learned from this is that Comet's are incredibly unpredictable.
There are several Comets due in 2014, most notably Comet 2013 A1, which will pass very close to Mars in October 2014, NASA say there is even a very small but real chance that Comet 2013 A1 will collide with Mars. Apparently the Comet is 1 to 3 km in diameter and travelling at 125,000 mph. If it hits Mars it would deliver as much energy as 35 million megatons of TNT. Not a good time to be a Martian. We'll write more about Comet 2013 A1 through 2014.