| CNN | - |
(CNN)
-- Hold the obituary. Experts now think Comet ISON -- or at least part
of it -- survived its close encounter with the sun. Karl Battams, a
comet scientist for the Naval Research Laboratory, said it is believed
some parts of ISON's nucleus survived perihelion.
N sweeps near sun, shows signs of life
updated 8:11 AM EST, Fri November 29, 2013
Comet ISON appears as a white
smear heading up and away from the sun on Thursday, November 28.
Scientists initially thought the comet had been disintegrated by the
sun, but images suggest a small nucleus may still be intact.
HIDE CAPTION
Comet ISON
STORY HIGHLIGHTS
- Comet ISON -- or at least part of it -- may have survived, experts say
- Earlier reports indicated ISON disintegrated
- The fate of the comet remains uncertain
- It was making its closest approach to sun
Karl Battams, a comet
scientist for the Naval Research Laboratory, said it is believed some
parts of ISON's nucleus survived perihelion.
"It now looks like some
chunk of ISON's nucleus has indeed made it through the solar corona, and
re-emerged," he said. "It's throwing off dust and (probably) gas, but
we don't know how long it can sustain that."
However, he said, its fate is uncertain.
"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 said.
ISON swept about 730,000 miles over the sun's surface Thursday about 2 p.m. ET.
A fleet of spacecraft watched ISON plunge toward the sun, including NASA's STEREO satellite, the European Space Agency/NASA SOHO spacecraft and the Solar Dynamics Observatory.
Comet ISON could be a record breaker
Comet could dazzle in December
Comets are giant
snowballs of frozen gases, rock and dust that can be several miles in
diameter. When they get near the sun, they warm up and spew some of the
gas and dirt, creating tails that can stretch for thousands of miles.
Most comets are in the
outer part of our solar system. When they get close enough for us to
see, scientists study them for clues about how our solar system formed.
Astronomers Vitali Nevski and Artyom Novichonok discovered ISON last year using a telescope near Kislovodsk, Russia.
ISON -- officially named
C/2012 S1 -- was 585 million miles away at the time. Its amazing
journey through the solar system had been chronicled by amateur
astronomers and by space telescopes.
"From the beginning,
ISON has confused, surprised and amazed us, and in hindsight its latest
little escapade really should not shock us," Battams said. "Nonetheless,
this has been one of the most extraordinary comets we have ever
encountered, and just goes to reiterate how beautiful, dynamic and
exciting our universe is."
Observers have been
watching the comet for more than a year, hoping it would survive its
sunbath and emerge to put on a sky show, visible to the naked eye in the
Northern Hemisphere.
Earlier Thursday, NASA
scientists had pretty much declared ISON dead at the end of a Google
Hangout to watch the comet swing by the sun. But professional and
amateur astronomers were undeterred by the reports and kept analyzing
NASA satellites. They found images that clearly show something emerging from the sun.
"What we see here is the
dust tail emerging first, pointing away from the sun," said Padma
Yanamandra-Fisher with the Space Science Institute and a member of the
ISON Observing Campaign.
A video made by observing campaign member John Maclean
shows the comet slicing toward the sun and then something -- apparently
ISON -- emerging from the other side. Maclean is a fellow of the Royal
Astronomical Society at Norman Lockyer Observatory Sidmouth in Devon,
England.
The discovery stunned many in the comet-watching community and led some to nickname ISON the zombie comet.
Others repeated an old joke about comets and cats.
"Comets are like cats; they have tails, and they do precisely what they want," David H. Levy said.
This comet also seems to have something else in common with cats -- nine lives.
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