NASA’s Dawn spacecraft has become the first mission to achieve orbit around a dwarf planet. The spacecraft was approximately 38,000 miles from Ceres when it was captured by the dwarf planet’s gravity at about 4:39 a.m. PST (7:39 a.m. EST) on March 6.
Mission controllers at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif. received a signal from the spacecraft at 5:36 a.m. PST (8:36 a.m. EST) that Dawn was healthy and thrusting with its ion engine, the indicator Dawn had entered orbit as planned. The JPL is home to the Spacecraft Assembly Facility, a Class 10,000 ISO 7 cleanroom with horizontal airflow and return.
“Since its discovery in 1801, Ceres was known as a planet, then an asteroid, and later a dwarf planet,” says Marc Rayman, Dawn chief engineer and mission director at JPL. “Now, after a journey of 3.1 billion miles and 7.5 years, Dawn calls Ceres, home.”
In addition to being the first spacecraft to visit a dwarf planet, Dawn also has the distinction of being the first mission to orbit two extraterrestrial targets. From 2011 to 2012, the spacecraft explored the giant asteroid Vesta, delivering new insights and thousands of images from that distant world. Ceres and Vesta are the two most massive residents of our solar system’s main asteroid belt between Mars and Jupiter.
The most recent images received from the spacecraft, taken on March 1 show Ceres as a crescent, mostly in shadow because the spacecraft’s trajectory put it on a side of Ceres that faces away from the sun until mid-April. When Dawn emerges from Ceres’ dark side, it will deliver ever-sharper images as it spirals to lower orbits around the planet.
“We feel exhilarated,” says Chris Russell, principal investigator of the Dawn mission at the University of California, Los Angeles. “We have much to do over the next year and a half, but we are now on station with ample reserves, and a robust plan to obtain our science objectives.”
Dawn’s mission is managed by JPL for NASA’s Science Mission Directorate in Washington. Dawn is a project of the directorate’s Discovery Program, managed by NASA’s Marshall Space Flight Center in Huntsville, Ala. UCLA is responsible for overall Dawn mission science. Orbital ATK Inc., in Dulles, Va., designed and built 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.
Release Date: March 6, 2015
NASA Craft Delivers New Image of Dwarf Planet: http://www.cemag.us/news/2015/01/nasa-craft-delivers-new-image-dwarf-planet
Spacecraft Begins Approach to Dwarf Planet: http://www.cemag.us/news/2014/12/spacecraft-begins-approach-dwarf-planet