14 DAY TRIAL // Mission controllers at the NASA Jet Propulsion Laboratory (JPL) in Pasadena, California, have just released two new images of the giant asteroid Vesta, which the Dawn spacecraft is currently flying away from. The views combine the last images the orbiter took of the protoplanet.
Dawn left Vesta's orbit a couple of weeks ago, and is currently headed towards the dwarf planet Ceres. Both Ceres and Vesta are located in the Inner Asteroid Belt (IAB), between the orbits of Mars and Jupiter. Arrival at the new science target is estimated to occur in February 2015.
The orbiter arrived at Vesta on July 16, 2011, for what was originally supposed to be a 1-year mission. However, NASA decided to extend its stay there by another few months, so the spacecraft only departed the asteroid this September.
During this time, Dawn collected a large number of images of the largest asteroid in the solar system. One of the main science goals this mission has is figuring out why the space rock did not go on to develop into a fully-fledged planet.
The same question puzzles astronomers in relation to Ceres as well. Though larger than Vesta, and classified as a dwarf planet, it too failed to grow beyond its current size, and investigators are very curious to learn why.
“Dawn has peeled back the veil on some of the mysteries surrounding Vesta, but we're still working hard on more analysis. So while Vesta is now out of sight, it will not be out of mind,” explains researcher Christopher Russell.
The expert, who holds an appointment as a professor at the University of California in Los Angeles (UCLA), is the principal investigator of the Dawn mission. This spacecraft is the first ever to attempt two orbital insertion maneuvers in the same mission.
Unlike most other NASA spacecraft, Dawn is powered by an advanced ion propulsion engine, which produces thrust through the steady ionization of xenon gas. The push this produces is not significant, but is constant. It takes 4 days for the spacecraft to accelerate to 60 miles (100 kilometers) per hour.
Scientists at JPL manage the mission for the Science Mission Directorate, at NASA Heaquarters in Washington DC. The lab is in turn managed by the California Institute of Technology, also in Pasadena.