Comet ISON is giving stargazer the biggest thrill of anticipation as astronomers waiting to see whether it will become a "great comet" or fizzle out on Nov. 28, Thanksgiving, when Comet Ison will makes its nearest pass to the sun.

Comet ISON was discovered in 2012 by two Russian scientists. They saw Comet ISON after it first left the Oort Cloud, which is a a cloud of comets believed to extend about a light-year from the sun. Comet ISON is named after the telescopes used in the International Scientific Optical Network.

Matthew Knight, a Lowell Observatory astronomer said the ISON comet "is going from the absolute coldest place in the solar system to the absolute hottest.

Michael Kelley an astronomer at the University of Maryland, College Park said "We've never had a comet that seems to come directly from the Oort Cloud, on its first passage to the inner solar system in four billion years, all the way to within three solar radii of the solar surface."

Dozens of telescopes will be aimed at Comet ISON and it will also be tracked in the visible, infrared, radio, x-ray and gamma-ray bands.  Mars rovers and satellites will also collect data on Comet ISON. So far it looks like Comet ISON's core is still intact.

Matthew Knight said "It's still brightening but it has not been brightening as rapidly as we would have hoped.  It's this unique combination where it's something from the Oort Cloud that's never experienced this heat before, and then it's coming into this extreme environment where the change in temperature and gravitational pull makes it hard for us to predict what's going to happen. It's such a unique appearance that even if it disappoints from the 'ooh and ah' standpoint, I think the science is going to be really interesting."

The Comet ISON will light up this sky at the end of November when it passes through earth's solar system. Comet ISON will approach the sun until it is at its closest point on Nov. 28. The comet will only be 724,000 miles above the surface of the sun. Researchers say the comet should blaze as brightly as a full moon.

Josh Sokol of the Space Telescope Science Institute in Baltimore, Md., posted "The result is part science, part art. It's a simulation of what our eyes, with their ability to dynamically adjust to brighter and fainter objects, would see if we could look up at the heavens with the resolution of Hubble."

The Space Telescope Science Institute operates the Hubble telescope.

Researcher explained that the pictures were taken by Hubble's Wide Field Camera 3 UVIS instrument. Three exposures were made with a filter that transmits yellow and green light, which shows up as blue in the picture. Two of the pictures two used a filter that allows red and some near-infrared light.

Sokol wrote, "In general, redder things are older, more evolved, than blue things - this is true both for the crosshair-spiked stars and the smudges of distant galaxies."

Comet ISON is being called the "comet of the century." Comets are made up of the building blocks that came together to form the planets 4.5 billion years ago. Scientists are looking forward to studying the material that ISON leaves in its aftermath is it approaches the sun.