NASA's Dawn spacecraft has closed within 300,000 miles of the second-largest object in the asteroid belt, Vesta, report mission managers.
"Vesta is coming more and more into focus," said team camera lead investigator Andreas Nathues, of the Max Planck Institute for Solar System Research, in a statement. "Dawn's framing camera is working exactly as anticipated."
Scheduled for a July 16, rendezvous with the 330-mile-wide asteroid, Dawn will begin slowing to 75-mile-per-hour speeds for the passage. The spacecraft uses an innovative ion propulsion systems, which provides a faint but steady push to the spacecraft, unlike the quick-firing bursts from normal rockets.
Once captured by the asteroid's gravity, the spacecraft will circle Vesta in a 9,900-mile-high orbit. Eventually the craft's ion's thrusters will next boost the spacecraft on to an encounter with the dwarf planet, Ceres, the largest object in the asteroid belt.