Scientists have discovered that a long-known asteroid in the solar system has a comet-like tail. The active asteroid, called 62412, is present in our solar system’s main asteroid belt between Mars and Jupiter. It is the first comet-like object found in the Hygiea family of asteroids. The unexpected discovery was made by Scott Sheppard of the Carnegie Institution and Chadwick Trujillo of the Gemini Observatory.
The long-known object reclassified as ‘active asteroid’
Asteroid 62412 was discovered in September 2000 by the Lincoln Near-Earth Asteroid Research (LINEAR) in New Mexico. For more than a decade, scientists believed it was a typical asteroid. In the past, asteroids were believed to be unchanging objects. But an improved observation ability allowed researchers to discover comet-like tails and commas.
The latest finding reclassifies the object as an “active asteroid.” They are a strange class of objects. They have stable orbits between those of Jupiter and Mars. However, active asteroids have tails of gas and dust, just like comets. What causes ejection of material and subsequent formation of the tail is unclear. But some theories state that the tail formation could be the result of recent impacts. It could also occur due to sublimation of surface ice from solid to gas.
What causes an asteroid to become active?
Scientists found that 62412 has an extremely fast rotation, which likely shifts material around its surface. Ejected material could create the tail. Sheppard and Chadwick said it is only 13th known active asteroid in the main asteroid belt. They think there could be over a hundred more, which are yet to be discovered. They also noted that the density for 62412 typical of asteroids is not consistent with comets.
Further study of the unusual object would confirm the source of the comet-like tail. It will help researchers determine the process that causes an asteroid to become active. Scientists will present their study at the American Astronomical Society’s Division for Planetary Science Meeting in Tucson this week.