Spacecraft aims for the Asteroid Belt

The Dawn satellite and mission were developed at NASA, the German Aerospace Center, Max Plank Institute for Solar System Research, Italian Space Agency, and Italian National institute of Astrophysics, as well as Orbital Science Corp., and Los Alamos National Laboratory. The Spacecraft will explore Vesta (left) and Ceres (right).

The Dawn satellite and mission were developed at NASA, the German Aerospace Center, Max Plank Institute for Solar System Research, Italian Space Agency, and Italian National institute of Astrophysics, as well as Orbital Science Corp., and Los Alamos National Laboratory. The Spacecraft will explore Vesta (left) and Ceres (right).


NASA's Dawn satellite will take off next month on an eight-year, 3.2 billion mile trip through the Asteroid Belt, a region between Mars and Jupiter. On its voyage, Dawn will explore the asteroid Vesta and Ceres, a dwarf planet in NASA parlance. Scientists hope these two dissimilar objects will give clues to the Solar System's early history. Vesta is a dry, evolved asteroid with surface features ranging from basaltic lava flows to a deep crater near its south pole. Ceres, in contrast, has a more primitive surface, but with evidence of water.

The spacecraft is the first to rely on ion propulsion, a technology initially tested on NASA's Deep Space 1 mission. Without the ion drive, Dawn's mission would be unaffordable, perhaps even impossible, says NASA. The engine will use xenon as fuel, ionizing and then accelerating it electromagnetically for thrust. Dawn carries a pair of solar panels that stretch 65 ft, tip to tip, and generate 10 kW of power.

The payload will include two cameras, a visible and IR-mapping spectrometer to determine the mineral composition of the surface, and a gamma ray and neutron spectrometer to identify elements that make up the outer shells of the asteroid and dwarf planet. Dawn will also use itself and its trajectory to calculate asteroids' gravitational fields and learn more about their interiors.

If all goes well, the spacecraft will fly close by Mars in March of 2009, pass Vesta in April 2012, approach Ceres in Feb. 2015, and end its mission five months later.