Story highlights NASA scientists watching material that emerged from the sun

Comet ISON may have evaporated, experts says

Spacecraft lose sight of the comet

Comet was making its closest approach to sun

Something emerged from the sun after Comet ISON made its closest approach today. Is it the ISON?

NASA scientists, professional and amateur astronomers are analyzing images from NASA satellites to learn more about comet's fate.

"We haven't seen any definite nucleus yet," said Padma Yanamandra-Fisher with the Space Science Institute and NASA's Comet ISON Observing Campaign.

Members of the group's Facebook page spotted what may be the remnants of ISON in satellite images soon after experts at NASA's Google Hangout on ISON said it looked like the comet had broken up and melted into the sun.

Comet watchers will have to wait until ISON, or what's left of it, are a bit further from the sun to get more information.

"What we see here is the dust tail emerging first, pointing away from the sun," Yanamandra-Fisher said.

But it is not clear if the comet's core, or nucleus, is intact, or if it's just a bunch of dust.

Observers were hoping that ISON would survive its Thanksgiving Day close encounter with the sun and emerge to put on a big sky show 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 in September 2012 using a telescope near Kislovodsk, Russia, that is part of the International Scientific Optical Network.

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.