Since its launch in 2007, NASA’s Dawn spacecraft has orbited and explored Vesta, a protoplanet, for 14 months within 2011 and 2012; and it is now approaching Ceres, a dwarf planet the size of Texas that had never been visited before.
Arriving Ceres on March 6, 2015, NASA’s Dawn spacecraft will have broken history as the first spacecraft to ever orbit two solar system bodies – Vesta and now Ceres. Dawn is now at its approaching phase as it bears down on Ceres, and it is currently at a distance of 400,000 miles or 640,000 kilometers from dwarf planet Ceres, and it is approaching at a speed of 450 miles or 725 kilometers per hour.
Dawn had recently been at the opposite side of the sun where it could barely communicate with antennas on Earth, but having been maneuvered to emerge from this point, it can now communicate freely with Earth again as it journeys toward Ceres.
Scientists and other space researchers know virtually nothing about this dwarf planet, and according to Christopher Russel, the principal investigator for the Dawn mission at the University of California in Los Angeles, “Ceres is almost a complete mystery to us. Ceres, unlike Vesta, has no meteorites linked to it to help reveal its secrets. All we can predict with confidence is that we will be surprised.”
However, researchers believe they understand a few difference between Vesta and Ceres. They believe Vesta formed first and then Ceres later, and it is also thought that Ceres is much colder in the inner side than Vesta. It is also believed that Vesta contained radioactive materials that enabled it to form some amount of water; while Ceres might have a thick ice mantle that may even contain an ocean under its icy crust.
Ceres is the largest body in the asteroid belt which lies between Mars and Jupiter with an average diameter of 590 miles or 950 kilometers, while Vesta is the second biggest body within the belt with an average diameter of 326 miles or 525 kilometers.
Using an ion propulsion to create propelling force for the spacecraft instead of the usual chemical propulsion used by other spacecrafts, Marc Rayman, the chief engineer and mission director for Dawn, based at NASA’s Jet Propulsion Laboratory in Pasadena, California, states that “Orbiting both Vesta and Ceres would be truly impossible with conventional propulsion. Thanks to ion propulsion, we’re about to make history as the first spaceship ever to orbit two unexplored alien worlds.”
By January 2015, Dawn will have moved closer to Ceres enough to transmit relevant data about the body back to Earth, and it also send the best quality of images as it progresses on. The Dawn mission to Vesta and Ceres is managed by JPL, a division of the California Institute of Technology in Pasadena, for NASA’s Science Mission Directorate, Washington. UCLA is responsible for overall Dawn mission science.