Washington: Astronomers from the University of Maryland at College Park (UMCP) and Lowell Observatory have used NASA`s Swift satellite to check out comet C/2012 S1 (ISON), which may become one of the most dazzling in decades when it goes around the sun later this year.
Using images acquired over the last two months from Swift`s Ultraviolet/Optical Telescope (UVOT), the team has made initial estimates of the comet`s water and dust production and used them to infer the size of its icy nucleus.
"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," Lead Investigator Dennis Bodewits, an astronomer at UMCP said.
Comet ISON is now approaching the inner solar system.
Discovered last year, the comet remains unusually active for its distance from the sun.
If current trends continue, ISON could rank as one of the brightest comets in decades when it makes its close approach to the sun in late November.
Additional factors, including an encounter with Mars followed by a scorching close approach to the sun, make comet ISON an object of special interest.
In late February, at NASA`s request, a team of comet experts initiated the Comet ISON Observing Campaign (CIOC) to assist ground- and space-based facilities in obtaining the most scientifically useful data.
Like all comets, ISON is a clump of frozen gases mixed with dust.
From now through October, comet ISON tracks through the constellations Gemini, Cancer and Leo as it falls toward the sun.
Based on ISON`s orbit, astronomers think the comet is making its first-ever trip through the inner solar system.
Formally designated C/2012 S1 (ISON), the comet was discovered on September 21, 2012, by Russian astronomers Vitali Nevski and Artyom Novichonok using a telescope of the International Scientific Optical Network located near Kislovodsk.