December 2, 2013
Comet ISON Does Not Survive Perihelion, Only A Ghost Remains
[ Watch the Video: The Life And Times Of Comet ISON ]
Lawrence LeBlond for redOrbit.com - Your Universe Online
Now after and up-and-down journey through the cosmos, ISON has seemingly met its match and it its fate has been sealed once and for all.
Astronomers for over a year have been calling ISON the “comet of the century,” claiming it was going to put on a spectacular show around Thanksgiving 2013. However, others had pegged the comet to actually “fizzle out” and not even offer us a glimmering chance of show.
But as the comet approached its perihelion with the sun on Thanksgiving Day it was sure to be a feast for the eyes for many. With several space observatories focused on ISON, the frozen chunk of gas, dust and debris made its final approach Thursday afternoon (Nov 28) at around 1:40pm EST.
As the comet raced across the sun at close to 700,000 miles overhead, all contact was lost between space watchers and the icy object. For hours, astronomers -- pro and amateur -- scratched their heads wondering if this was in fact the end of the “comet of the century.” Some most assuredly made those “I told you it would fizzle out” faces.
[ Watch the Video: Comet ISON's Full Perihelion Pass ]
But after several hours of not knowing the fate of the comet, some sign was picked up on the other side of the sun that comet ISON had in fact survived its perihelion encounter with the fiery behemoth.
Prior to this reemergence, astronomers were readying to hammer that final nail into ISON’s coffin.
“At this point, I do suspect that the comet has broken up and died,” Karl Battams, a comet scientist with the Naval Research Laboratory, said during a Google+ hangout from Arizona’s Kitt Peak Observatory on Thursday. “Let’s at least give it a couple of more hours before we start writing the obituary.”
And a few more hours is all Battams, as well as his colleagues, needed.
By late Thursday, the comet showed signs that it was still alive and well, or so it seemed.
“It now looks like some chunk of ISON’s nucleus has indeed made it through the solar corona, and re-emerged,” Battams said in an interview with CNN’s Amanda Barnett on Friday. “It’s throwing off dust and (probably) gas, but we don’t know how long it can sustain that.”
He maintained that it would take a few days of observations to get a feel for how ISON made out on its one-way ticket to perihelion.
“Now it has emerged and started to brighten, we need to observe it for a few days to get a feel for its behavior,” Battams noted.
With that being said, today it is clearer that ISON did in fact not survive its ordeal with the sun.
[ Watch the Video: When Ice Meets Fire ]
It is evident that the sun’s ferocity was more than the comet could handle, receiving a fatal blow from its perihelion. What is left from the once great and powerful is just a headless dusty ghost of a comet.
When NASA’s Solar Dynamics Observatory caught the last glimpse of ISON fading behind the sun, it was hours before the space agency’s SOHO spacecraft picked it up on the other side. Apart from appearing to survive the encounter, the comet also seemed to make a hairpin turn around the sun, appearing to brighten up and forming a fan-shaped tail.
The reemergence of the comet left many feeling optimistic that ISON would live to fight another day. But by Sunday, Dec 1, experts were painting a pretty clear picture of what really happened. Instead of forming a new zombie-like state, the comet had actually disintegrated and left in its wake just the glowing ghostly remains of a once frozen ball of gas, dust and debris. New satellite imagery does indeed show the comet’s remains are fading fast as it continues its recession from the sun.
“I think for the most part it’s dead,” C. Alex Young, the associate director for science in the heliophysics division at NASA’s Goddard Space Flight Center in Greenbelt, Md, told Kenneth Chang of the NY Times. “The folks are finally pretty confident that’s the case.”
“I really don’t think there’s a whole lot left,” added Battams. “I’m very disappointed for the public, because we’re not going to see this beautiful object in the Northern Hemisphere skies.”
Enthusiastic astronomers were hoping for a spectacular showing of ISON post-perihelion. But it now looks as if there will be no flashy sky show for millions of backyard space enthusiasts.
Experienced astronomers might be able to capture some of the fading ghostly remains in the pre-dawn sky in the coming days and weeks, but there will be no chance of a naked-eye encounter, according to a statement on spaceweather.com.
On the scientific side, the excitement of observation is over. Now, it will take weeks or perhaps months for scientists to piece together the data to get a better understanding of what really happened. Scientists believe understanding what happened to ISON could offer better information about the composition of the comet and its tumultuous journey, as well as information on how planets form.
“Scientifically, I don’t know if it gets much better than seeing the comet being ripped apart, falling apart right before your eyes,” Dr. Battams said.
While there is not much left of the comet, it can’t be laid to rest quite yet. Many space satellites, observatories and telescopes will continue to monitor the dusty remains of ISON as it heads back out to the frigid regions of space, likely to never return again.