Showing posts with label ISON. Show all posts
Showing posts with label ISON. Show all posts
Thursday, December 05, 2013
What Happened to Comet ISON? | VIDEO
Astronomers have long known that some comets like it hot. Several of the greatest comets in history have flown close to the sun, puffing themselves up with solar heat, before they became naked-eye wonders in the night sky.
Some comets like it hot, but Comet ISON was not one of them.
The much-anticipated flyby of the sun by Comet ISON on Thanksgiving Day 2013 is over, and instead of becoming a Great Comet….
"Comet ISON fell apart," reports Karl Battams of NASA's Comet ISON Observing Campaign. “The fading remains are now invisible to the human eye.”
At first glance this might seem like a negative result, but Battams says “rather than mourn what we have lost, we should perhaps rejoice in what we have gained—some of the finest data in the history of cometary astronomy.”
On the morning of Nov. 28th, expectations were high as ISON neared perihelion, or closest approach to the sun. The icy comet already had a riotous tail 20 times wider than the full Moon and a head bright enough to see in the pre-dawn eye with the unaided eye. A dose of solar heat could transform this good comet into a great one.
During the flyby, more than 32,000 people joined Battams and other solar scientists on a Google+ Hangout. Together they watched live images from a fleet of solar observatories including the twin STEREO probes, the Solar Dynamics Observatory, and SOHO. As Comet ISON approached the sun it brightened and faded again.
"That might have been the disintegration event," says Matthew Knight of NASA's Comet ISON Observing Campaign.
Saturday, November 30, 2013
Comet ISON is Back From the Dead! | VIDEO
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Click to view a SOHO coronagraph movie of the solar flyby
COMET ISON LIVES!
By spaceweather.com
11-29-13
COMET ISON LIVES! Cancel the funeral. Comet ISON is back from the dead. Yesterday, Nov. 28th, Comet ISON flew through the sun's atmosphere and appeared to disintegrate before the cameras of several NASA and ESA spacecraft. This prompted reports of the comet's demise. Today, the comet has revived and is rapidly brightening.
Before the flyby, experts had made many predictions about what might happen to the comet, ranging from utter disintegration to glorious survival. No one predicted both.
Karl Battams of NASA's Comet ISON Observing Campaign says, "[colleague] Matthew Knight 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 long thin tail we saw in the [SOHO coronagraph] images. Then, as ISON plunged through the corona, it continued to fall apart and vaporize, losing its coma and tail completely just like sungrazing Comet Lovejoy did in 2011. 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." . . .
Monday, September 09, 2013
Comet ISON Offers Doomsday Deja Vu | VIDEO
We think a wayward comet is the leading culprit in the extinction of the dinosaurs 65 million years ago. But has a comet ever killed anyone? The Tunguska atomic bomb-sized blast in 1908 could have, if the comet had exploded over a city rather than desolate Siberia. . . .
. . . Now that Comet ISON is heading for a close encounter with the sun in late November, the Internet is again abuzz with UFO ghost tales, not to mention doomsday theories, mysticism, and miscellaneous strange ideas that go bump in the night.
For starters let’s look at the UFO allegations. A selection of pictures form the Hubble Space Telescope data archive were interpreted by some UFO sleuths as an image of a spaceship, not a diminutive icy nucleus of a primeval body.
Among the online speculation:
“Cloaked and seen engines”
“The winged planet”
“Klingon battle formation”
“This isn’t how they wanted us to see it!”
“Game changer”
In reality the comet is streaked because Hubble wasn’t tracking it in the particular series of five exposures originally posted on a comet blog. The moving comet left a trail in the exposures and appeared to follow an arc due to the fact that Hubble is also moving through space in Earth orbit. Similar trails are commonly seen in other Hubble fixed target observations of background stars where a moving asteroid strays into the field of view and can trace out a “C” or “S” shape on the camera detector.
A comprehensive explanation of this ISON image can be seen below:
Sunday, September 08, 2013
Is Comet ISON a UFO? Hubble's Scientists Do a Reality Check
By Alan Boyle
NBC News
9-6-13
It's not at all certain that Comet ISON will turn out to be the "comet of the century," as hoped, but a couple of things are certain: It's not an alien spaceship, and it hasn't split up into three pieces.
Those were apparently questions on the minds of some folks last month, thanks to a flurry of videos and blog postings based on imagery from the Hubble Space Telescope's archives. The hoohah got hot enough to merit an official response, posted to the Space Telescope Science Institute's archive website and its ISON Blog.
It all started with a series of images captured by Hubble's Wide Field Camera 3 UVIS instrument on April 30. Various exposures were combined to produce a widely distributed color picture of Comet ISON against a background field of stars. When Internet sleuths took a close look at the archived image, it looked as if there were three separate objects hiding in the glare of ISON's coma.
Was ISON breaking up? Was the comet being escorted by two alien spacecraft? . . .
Sunday, March 31, 2013
NASA Spacecraft Snaps New Photo of Potential 'Comet of the Century'
A NASA spacecraft scanning for the most powerful explosions in the universe has captured a photo of Comet ISON, an icy wanderer that could potentially dazzle stargazers when it swings close to the sun later this year.
NASA's Swift satellite, which is typically used to track intense gamma-ray bursts from distant stars, photographed Comet ISON on Jan. 30, with the space agency unveiling the photo today (March 29). By tracking the comet over the last two months, Swift has allowed astronomers to learn new details about how large the comet is and how fast it is spewing out gas and dust.
"Comet ISON has the potential to be among the brightest comets of the last 50 years, which gives us a rare opportunity to observe its changes in great detail and over an extended period," said Lead Investigator Dennis Bodewits, an astronomer with University of Maryland at College Park (UMCP) who helped obtain the new image.
Some astronomers have predicted that ISON could be the "Comet of the Century" when it makes its closest approach to the sun in late November. But a recent analysis found that the comet is not brightening as expected, and may have a ways to go to meet such expectations. . . .