NASA's HiRISE Camera Captures Comet ISON Heading Toward the Sun

NASA's multipurpose spacecraft orbiting around the Red planet captured images of the icy  Comet ISON, dubbed the 'comet of the century' as it was making its way into the inner Solar System for a close encounter with the Sun

NASA's Mars Reconnaissance Orbiter focused its High Resolution Imaging Science Experiment (HiRISE) camera on the Comet ISON, a sungrazer, to capture images as the cosmic planet cruised by the red planet 'Mars'.

It was on September 21, 2012 that Comet ISON was initially discovered by a Russian amateur astronomers Artyo  Novichonok and Vitali Nevski. The bright comet will appear on the Thanksgiving Day and poses no threat to earthlings. On its closet approach to Earth on December 26, the comet will fade.

In order to measure the brightness of the cosmic body, the HiRISE camera was set to capture images of the cruising comet.

HiRISE captured the bright speeding ball of ice. The pictures show a fuzzy bright spot. The comet's coma is extremely faint and the images will help researchers gain a better understanding of the size of the comet's nucleus including its overall brightness. These are important markers to study behavior of the bright comet.

Preliminary analysis of the data reveals that the comet is present at the lower end of the brightness range. This  makes it difficult  to view the image clearly, the low coma activity confines the size of the nucleus.

".....This image has a scale of approximately 8 miles (13.3 km) per pixel, larger than the comet, but the size of the nucleus can be estimated based on the typical brightness of other comet nuclei. The comet, like Mars, is currently 241 million kilometers from the Sun. As the comet gets closer to the sun, its brightness will increase to Earth-based observers and the comet may also become intrinsically brighter as the stronger sunlight volatilizes the comet's ices," explain researchers Alan Delamere and Alfred McEwen in a press release.

At the end of this year, the comet will be visible in the night sky to the naked eye. On Nov. 28, the comet will travel at a distance of 1.2 million kilometers above the Sun's visible surface. This sungrazer is expected to put up a spectacular show in the Northern Hemisphere. If the comet survives the encounter at the end of the year, the icy ball will glow 15 times brighter than the moon even in the broad day light. A giant balloon named BRRISON will be launched by NASA to study the comet.