时间:2011-08-05 13:52 作者:admin 来源:网络
太空探测器黎明号将绕灶神星Vesta运行以进一步了解太阳系的形成International Space Mission Explores New Frontier
An international space mission is spiraling toward the asteroid Vesta on a mission to learn more about the formation of the solar system, NASA announced at an August 1 press briefing.
Dawn is a joint project of NASA, the German Aerospace Center, the Max Planck Institute for Solar System Research, the Italian Space Agency and the Italian National Astrophysical Institute. It is the first probe to enter orbit around an object in the main asteroid belt between Mars and Jupiter.
The spacecraft will provide in-depth analysis of Vesta, which scientists believe is the source of a large number of meteorites that fall to Earth. Dawn will spend one year orbiting Vesta, then travel to the dwarf planet Ceres. The two bodies are the most massive objects in the asteroid belt.
“We have been calling Vesta the smallest terrestrial planet,” Chris Russell, Dawn’s principal investigator, said at the news conference. “The latest imagery provides much justification for our expectations. They show that a variety of processes were once at work on the surface of Vesta and provide extensive evidence for Vesta’s planetary aspirations.”
Observations collected throughout the mission will provide unprecedented data to help scientists understand the earliest chapter of our solar system and its formation almost 4.5 billion years ago.
“Now that we are in orbit around one of the last unexplored worlds in the inner solar system, we can see that it’s a unique and fascinating place,” said Marc Rayman, Dawn chief engineer and mission manager at NASA’s Jet Propulsion Laboratory in Pasadena, California.
Dawn will be the first spacecraft to orbit two celestial objects in the solar system. By investigating the two very different asteroids, with the same instruments on the same spacecraft, the research team hopes to compare the different evolutionary path each took, create a picture of the early solar system and provide opportunities for significant breakthroughs in knowledge of how it formed.
“It is fantastically exciting that we will begin providing humankind its first detailed views of one of the last unexplored worlds in the inner solar system,” Rayman said.
Dawn will be in the approach phase of the Vesta orbit for about three weeks, during which the team will search for possible moons around the asteroid, obtain more images for navigation and observe Vesta’s physical properties.
The total cost of the mission, launched September 27, 2007, is $466 million, which includes 10 years of operations and data analysis. The mission is scheduled to conclude in 2015.