Christopher Russell
The UCLA scientist who led NASA's Dawn mission, which orbited Vesta and Ceres and confirmed that the HED meteorites come from Vesta.
Key facts
- Born
- 1943
- Nationality
- American
- Field
- Space physicist
Christopher T. Russell is a space physicist at the University of California, Los Angeles. For much of his career he studied the magnetic fields of planets and of the solar wind, and he built instruments for many NASA missions.
He was principal investigator of Dawn, the first spacecraft to orbit two different bodies beyond the Moon. Dawn used ion engines, which push the spacecraft gently but for a very long time, to travel through the asteroid belt. It was launched in 2007 and entered orbit around Vesta in July 2011.
For 14 months Dawn mapped Vesta in detail. It found two giant overlapping impact basins near the south pole, the larger, named Rheasilvia, about 500 kilometres across with a central peak more than 20 kilometres high. These impacts threw out enormous amounts of rock, which explains the family of small asteroids and the HED meteorites that reach Earth. Dawn's instruments found minerals and chemistry on Vesta's surface matching howardites, eucrites and diogenites.
Dawn then travelled on to the dwarf planet Ceres, arriving in 2015. It found bright spots of salts in the crater Occator, signs that briny water once reached the surface. The mission ended in 2018 when the spacecraft ran out of fuel, and it still circles Ceres.
On the timeline
- 16 July 2011Dawn arrives at Vesta