According to NASA, this most recent error was likely a repeat of a similar phenomenon that struck the Dawn probe in 2011. Three years ago an electrical component controlling Dawn’s ion-thrusters was pinged by a high-energy radiation particle. This interference was enough to send the thruster’s system into safe mode and shut down all propulsion.
Discussing Dawn’s recent hiccup Marc Rayman, Dawn’s Chief Mission Director and Engineer said, “We followed the same strategy that we implemented three years ago to recover from a similar radiation strike – to swap to one of the other ion engines and a different electronic controller so we could resume thrusting quickly". But rather than scrapping the engine altogether, Rayman hopes to bring the faulty engine back online. “ [W] e have a plan in place to revive this disabled component later this year."
Launched in 2007, Dawn is travelling to the asteroid belt with the aim of investigating both the protoplanet Vesta and dwarf planet Ceres. While the mission was originally scheduled to rendezvous with Ceres in March of 2015, the twin phenomena have set the mission timetable back. As of now the Dawn is set to reach Ceres sometime in April 2015, a full month behind schedule.
Once Dawn arrives at its position shadowing Ceres, the probe will begin examining the icy geology that constitutes the massive rock. With the information that’s garnered from the rendezvous, scientists back on Earth will have a better understanding of how planets formed in early stages of our solar system’s evolution.
Image Courtesy of NASA