Astronomers are reporting an unexpected outburst by comet C/2012 X1 (LINEAR), although it is not clear whether the object is breaking up or whether a bright jet of material is simply blasting copious quantities of gas and dust into space.
Veteran comet hunters Ernesto Guido, Nick Howes and Martino Nicolini used a remote controlled telescope located in New Mexico to observe the spherical explosion on Oct. 21, revealing a bright coma exhibiting a 100-fold brightness increase. The comet is currently 450 million kilometers (approximately 3 AU) from Earth in the constellation Coma Berenices.
“The predicted magnitude of the comet on Oct. 20th was about +14,” Guido told Spaceweather.com. “Now it is close to +8.5.”
At this magnitude, backyard telescopes should be able to pick out the faint ball of reflected light. By the astronomers’ reckoning, the comet’s coma is approximately 260,000 kilometers (160,000 miles) in diameter.
As noted by Spaceweather.com’s Tony Phillips, this explosion does not necessarily mean the comet has been blown apart. A vein or cavern in the cometary nucleus may have been exposed to sunlight, causing rapid evaporation of the volatiles. The rapid sublimation of ices could be injecting gas and dust into the coma, generating its current appearance. Only followup observations over the coming weeks will confirm the outburst’s true nature and whether the comet survived the eruption intact.
Image credit: Ernesto Guido, Nick Howes and Martino Nicolini/remanzacco.blogspot.com