MESSENGER is a scientific investigation of the planet Mercury. Understanding Mercury, and the forces that have shaped it, is fundamental to understanding the terrestrial planets and their evolution. Just what is a terrestrial planet? It is a group of planets that are like Earth.
The MESSENGER spacecraft will orbit Mercury following three flybys of that planet. The orbital phase will use the flyby information as an initial guide to perform a focused scientific investigation of this mysterious world.
MESSENGER will enter Mercury orbit in March 2011 and carry out comprehensive measurements for one Earth year. The data-collection phase of the mission will conclude in March 2012.
