June 07, 2010 PASADENA, Calif.-- Deep in the heart of the
asteroid belt, on its way to the first of the belt's two most
massive inhabitants, NASA's ion-propelled Dawn spacecraft has
eclipsed the record for velocity change produced by a
spacecraft's engines. The previous standard-bearer for velocity
change, NASA's Deep Space 1, also impelled by ion propulsion,
was the first interplanetary spacecraft to use this technology.
The Deep Space 1 record fell on Saturday, June 5, when the Dawn
spacecraft's accumulated acceleration over the mission exceeded
4.3 kilometers per second (9,600 miles per hour). "We are using
this amazing ion-engine technology as a stepping-stone to orbit
and explore two of the asteroid belt's most mysterious objects,
Vesta and Ceres," said Robert Mase, Dawn project manager from
NASA's Jet Propulsion Laboratory in Pasadena, Calif. A
spacecraft's change in velocity refers to its ability to change
its path through space by using its own rocket engines. This
measurement of change begins only af