‘Healthy and thrusting’ Dawn becomes first spacecraft to orbit a dwarf planet

9 Mar 2015

Ceres, seen from Dawn spacecraft on 1 March, at a distance of about 48,000km. Image via NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

US space agency NASA’s Dawn spacecraft has just become the first to orbit two extra-terrestrial targets, having reached the orbit of dwarf planet Ceres.

In the wee hours of Friday morning, Dawn sent a signal back to NASA’s Jet Propulsion Laboratory (JPL) in California, confirming it was in Ceres’ orbit, and that it was “healthy and thrusting with its ion engine”.

“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 station with ample reserves, and a robust plan to obtain our science objectives.”

A seasoned pro

A couple of years back, Dawn explored the giant asteroid Vesta, capturing thousands of images. Its rendez-vous with Ceres means Dawn has now visited the two “most massive residents” in the main asteroid belt of our solar system, situated between Mars and Jupiter.

Ceres’ original discovery by Giuseppe Piazzi back in 1801 was at a time of fantastic focus on the skies, with a team of 24 astronomers around the world, named the ‘Himmelspolizei’ (Celestial Police), searching for a new planet in between Mars and Jupiter.

First thought of as a comet, Ceres was eventually established as a planet, and then a dwarf planet, with Dawn’s work the culmination of more than 200 years monitoring the mass.

“Now, after a journey of 4.9bn km and 7.5 years, Dawn calls Ceres home,” said Marc Rayman, Dawn chief engineer and mission director at JPL.

Gif of Ceres’ surface, captured last week. Image via NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Gordon Hunt was a journalist with Silicon Republic