NASA Spacecraft Becomes First to Orbit a Dwarf Planet

NASA's Dawn spacecraft has become the first mission to attain orbit about a dwarf planet. The spacecraft was about 38,000 miles (61,000 kilometers) from Ceres when it was taken by the dwarf planet’s gravity at about 4:39 a.m. PST (7:39 a.m. EST) Friday.

Mission supervisors at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California received a signal from the spacecraft at 5:36 a.m. PST (8:36 a.m. EST) that Dawn was well and thrusting with its ion engine, the indicator Dawn had achieved orbit as intended.

"Since its finding in 1801, Ceres was known as a planet, then an asteroid and later a dwarf planet," said Marc Rayman, Dawn chief engineer and mission director at JPL. "Now, after a voyage of 3.1 billion miles (4.9 billion kilometers) and 7.5 years, Dawn calls Ceres, home."

Ceres is seen from NASA's Dawn spacecraft on March 1, just a few days before the mission achieved orbit around the previously unexplored dwarf planet. The image was taken at a distance of about 30,000 miles (about 48,000 kilometers).
Image Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

In addition to being the first spacecraft to visit a dwarf planet, Dawn also has the distinction of being the first mission to circle two extraterrestrial targets. From 2011 to 2012, the spacecraft studied the massive asteroid Vesta, conveying new insights and thousands of pictures from that distant world. Ceres and Vesta are the two most enormous inhabitants of our solar system’s main asteroid belt between Mars and Jupiter.

The latest pictures received from the Dawn, taken on March 1 show Ceres as a crescent, mostly in shadow as the spacecraft's path put it on a side of Ceres that faces away from the sun until mid-April. When Dawn arises from Ceres' dark side, it will convey ever-sharper pictures as it spirals to lower orbits about the planet.

"We feel exhilarated," said Chris Russell, principal investigator of the Dawn mission at the University of California, Los Angeles (UCLA). "We have much to do over the next year and a half, but we are now on position with plenty of reserves, and a healthy plan to obtain our science objectives."

Dawn's mission is supervised by JPL for NASA's Science Mission Directorate in Washington. Dawn is a mission of the directorate's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Alabama. UCLA is accountable for overall Dawn mission science. Orbital ATK Inc., in Dulles, Virginia, designed and made the spacecraft. The German Aerospace Center, Max Planck Institute for Solar System Research, Italian Space Agency and Italian National Astrophysical Institute are international partners on the mission team.




Post A Comment: