After charting the second-largest asteroid in the solar system for a period of 13 months, NASA probe Dawn has begun its journey away from the Asteroid Vesta to embark upon its sojourn to the asteroid belt located between Mars and Jupiter to rendezvous with Vesta’s more esteemed colleague, the dwarf planet Ceres.
On Wednesday, the NASA probe sent a signal to mission control, confirming that it had left the gravitational bounds of Vesta, which it had been orbiting since July of last year, and begun its journey towards Ceres. The near dwarf planet is the largest asteroid in the solar system, being 950km wide, while Vesta was relatively smaller - 530km wide. It is expected that Dawn will reach the dwarf planet around 2015.
Over the course of its 13-month observation, the probe has amassed a wealth of data about the asteroid, studying both its northern and southern pole, the various geological formations on the asteroid’s surface as well as its mineral composition from what was able to be observed on Vesta’s surface.
As an almost parting shot, in the moments that Dawn begin its journey away from the asteroid, it was able to observe the asteroid’s northern pole, with the sun having risen high enough for the probe to see the asteroid’s northern-most latitudes for the first time. Unlike the southern pole, that had, in Vesta’s past, been subject to a violent collision that chipped off a considerable amount of the asteroid’s mass, leaving the southern region pockmarked, the northern pole was relatively smoother. But according to NASA scientists, they would have to study Vesta’s data before making any statements.
“We haven't got together to discuss it carefully yet. [The region] is not as jumbled as I had expected; it's more subtle than I had expected. But the people who are experts in this particular area do feel that there is an effect of the southern impact,” said Dawn principal investigator Prof. Chris Russell.
With the help of the data that Dawn has gathered, scientists have been able to chart a history for Vesta. According to their research, Vesta is unique because it is one of the oldest known bodies in the solar system, comprised of the original objects that came together to form the planets around 4.6 billion years ago.
Now on its way to Ceres, the Dawn probe is sure to reveal much about the dwarf planet.