Huge Asteroid May in Fact Be a Comet

Recent observations conducted on a large asteroid revealed that the space body may not be a barren rock after all, but rather a dormant comet of some kind, that is only now beginning to come back to life.

Astronomers found 596 Scheila, the object in question, more than 100 years ago, and have always been convinced that it is an asteroid, as all available data pointed to that conclusion.

But the new information appear to go against this established knowledge. The 70-mile (113-kilometer) wide object is starting to develop a small, yet visible tail, similar to the gas clouds that trails comets.

What is even more peculiar about this particular object is that it lies in the inner asteroid belt, which is located between the orbits of Mars and Jupiter. This formation contains numerous asteroids, but very few comets.

In fact, if 596 Scheila is proven to be a comet, it would only be the sixth ever discovered in this area of the solar system. The inner asteroid belt contains such objects as Vesta, the largest known asteroid, and the dwarf planet Ceres, both of which are the targets of the NASA Dawn mission.

Experts imaged the “transformation” that the asteroid underwent into a comet on the night of December 11, when astronomers at the Catalina Sky Survey in Tucson, Arizona were surveying the night sky for potentially-dangerous near-Earth objects (NEO).

The goal of such investigations is to find unknown space rocks in Earth's vicinity, that other telescopes cannot pick up. As the recent NEO study was taking place, experts came across 596 Scheila.

But, unlike in other images, the appearance of the rock had changed. It had a bright core and a very faint trail. This was evidenced in a series of four images taken over a time frame of 30 minutes.

“Its brightness of a total magnitude of 13.4 visual, which is about 900 times fainter than the faintest star you can see in a clear, dark sky, led me to suspect that it was a known comet, but I checked the comet database and got nothing,” says Catalina astronomer Steve Larson.

“Scheila, along with several other bodies in the past few years, have created a new class of solar system objects: main-belt comets,” explains NASA Meteoroid Environment Office expert Bill Cooke.

“These bodies are an anomaly and a mystery since an object this close to the sun should have had its ices vaporized away,” adds the scientist. The Office is based at the Marshall Space Flight Center, in Huntsville, Alabama.

Follow-up studies conducted by other astronomers have evidenced that the outburst on the surface of 596 Scheila is made up of dust plumes. Future researches will attempt to determine whether any ice is present, Space reports.