Lazarus Comets Discovered In Cosmic Graveyard

 Courtesy photo – NASA

The asteroid belt comets – or ABCs for short – lie in the main asteroid belt between Mars and Jupiter, as stated by NASA’s expert Carolyn Crown, at a distance of 2,12 – 3,3 astronomical units (an astronomical unit is the average distance between the Sun and Earth).

The asteroid belt contains at least 85,000 dormant and extinct rocky comets, reports Dr. Ignacio Ferrin, who is a recognized astronomer.

This region of the outer space is estimated to contain at least 500,000 objects ranging from 1 m to 987 km in length – which is the size of Ceres, the smallest of the so far discovered five dwarf planets – although it is believed that several million more remain undiscovered.

Astronomers also claim to have discovered a new type of comet-like bodies they have dubbed “Lazarus comets”, so-called because they seem to have risen from the dead. “Some of these objects are actually dormant comets rather than extinct asteroids”, said Dr. Ferrin.

Comets become extinct when they have expelled most of their water content. However, dormant comets may become active by increased solar energy. This will happen if the comet’s perihelion distance is reduced due to planetary perturbations that can move comets into new orbits bringing them closer to the Sun.

When heated by the Sun, the comet’s water content starts to sublimate, then dormant comets become rejuvenated and activated as long as their energy lasts.

The study conducted by astronomers Ignacio Ferrin, Jorge Zuluaga and Pablo Cuartas of the University of Antioquia Department of Astronomy, has been accepted for publication in the upcoming issue of Monthly Notices of the Royal Academic Society.

The newly discovered asteroid belt, which may have originated many millions of years ago, is home to some of the so-called short-period comets with orbital periods less than 9,5 years.

While conducting research on the remnants of the formation of the solar system in the asteroid belt, the astronomers found that many of the presumed asteroids were actually dormant comets.

The discovery was made possible by recent findings about comets that appear to have anomalously low activity. However, several were discarded since their surface showed clear evidence of recent impacts, which accounts for the lack of sublimation.

Astronomers estimate that 17 percent of the asteroid belt’s population consists of extinct or dormant comets.

Although the asteroid belt is littered with celestial bodies, NASA estimates that the distances between these objects range from one to three million kilometers.

So far, only a dozen spacecraft have explored the asteroid belt. Recently, NASA’s Dawn probe visited a massive asteroid called Vesta, home to the tallest mountain ever discovered in the solar system (22 km). Dawn’s new target is the dwarf planet Ceres, which Dawn is expected to reach in early 2015.