Planned for launch in June 2007, Dawn will reach Vesta in 2011 and Ceres in 2015. Dawn's goal is to characterize the conditions and processes of the solar system's earliest epoch by investigating in detail these 2 asteroids, two of the largest protoplanets remaining intact since their formations. Ceres and Vesta reside in the extensive zone between Mars and Jupiter together with many other smaller bodies, called the asteroid belt. Each has followed a very different evolutionary path constrained by the diversity of processes that operated during the first few million years of solar system evolution.

By observing both minor planets with the same set of instruments, Dawn will provide new answers to questions about the formation and evolution of the early solar system.
 

Dawn will be the first purely scientific mission to be powered by ion propulsion, an advanced technology successfully demonstrated by NASA's Deep Space 1 mission. The use of solar electric ion thrusters will enable Dawn to orbit both asteroids in one mission, a feat that has not been attempted before.

The mission's science goals are to understand the conditions and processes in place at the beginning of solar system formation. Scientists also hope to gain a new understanding of the role of water in asteroid evolution.

Dawn's science instruments will:

- measure the asteroids mass, shape, volume and spin state
- record detailed elemental and mineral composition
- determine tectonic and thermal history, magnetism and core size
- examine the internal structure to compare these two very different bodies, one cool and wet, the other hot and dry