Launch date: 27 September 2007
Mars flyby date: 18 February 2009
Vesta orbit operations: July 16, 2011 - Sept. 5, 2012
Ceres orbit operations: March 6, 2015 - Oct. 31, 2018
The Dawn mission launched in Sept. 2007 to rendezvous and orbit the asteroids 4 Vesta and 1 Ceres. Vesta orbit operations took place from July 2011 to Sept. 2012, and Ceres orbit operations from March 2015 to Oct. 2018. The scientific objectives of the mission were to characterize the asteroids' internal structure, density, shape, size, composition and mass and to return data on surface morphology, cratering, and magnetism.