Even though Vesta is the second-largest body in the Main Asteroid Belt
, it still is small enough not to have been molded into a sphere by the pull of its own gravity, and it has retained its status as an asteroid.
Southwest Research Institute (SwRI) was part of an international team that recently discovered a relatively unpopulated region of the main asteroid belt
, where the few asteroids present are likely pristine relics from early in solar system history.
Dawn became the only spacecraft ever to orbit a cosmic body in the main asteroid belt
between Mars and Jupiter in 2011 when it began circling the asteroid Vesta.
In July 2011, Dawn reached its first destination, Vesta, the second most massive object in the main asteroid belt
. It spent nearly 14 months orbiting and mapping Vesta, returning more than 30,000 images and other measurements of the protoplanet.
Dawn is approaching dwarf planet Ceres in the main asteroid belt
with arrival expected in March 2015.
The object first caught astronomers' attention last September 15th, when the Catalina and Pan-STARRS sky surveys detected it as a fuzzy, comet-like object near the inner edge of the main asteroid belt
. Follow-up observations showed it to be three co-moving bodies enshrouded in a large, dusty envelope.
From the amount of sky searched, Sheppard and Trujillo determine that about 900 objects with orbits like Sedna and 2012 VP113 and sizes larger than 1000 km may exist and that the total population of the inner Oort cloud is likely bigger than that of the Kuiper Belt and main asteroid belt
. "Some of these inner Oort cloud objects could rival the size of Mars or even Earth.
Particularly in the solar system's main asteroid belt
- between Mars and Jupiter -- the researchers found a compositionally diverse mix of asteroids.
Asteroids, meanwhile, primarily are found in the Main Asteroid Belt
between Mars and Jupiter, although there are other large populations of these rocky objects that dwell elsewhere.
The results match exactly what would be expected if the moon were hit first by objects from the main asteroid belt
during a period called the Late Heavy Bombardment, roughly 3.9 billion years ago, and then later by smaller near-Earth asteroids that had been ejected from the belt, says Strom.
They are small rocky objects that move in elliptical orbits in the main asteroid belt
between the orbits of Mars and Jupiter.
According to its (https://dawn.jpl.nasa.gov/) official website , the Dawn, "is the only spacecraft ever to orbit two destinations beyond Earth and the only to orbit an object in the main asteroid belt
between Mars and Jupiter."