Richard P. Binzel, associate professor of planetary sciences, has assisted in crafting a cooperative two-nation mission to gather samples from asteroid Nereus in 2003 and will continue gathering data about Nereus before the mission is launched.
Professor Binzel has been an advisor to NASA in that agency's discussions with Japan's Institute of Space and Astronautical Science (ISAS), helping negotiate the scientific exchange that will make the mission possible. He has also been designated by NASA as the scientist responsible for making reconnaissance observations of Nereus using the giant Keck telescope in Hawaii. The data he obtains will give NASA and ISAS information about the asteroid's composition, which will help determine the best way to collect samples.
The mission, known as MUSES-C, is the first to collect samples from the surface of an asteroid and return them to Earth for in-depth study. MUSES-C will be launched on a Japanese M-5 launch vehicle in January 2002 from Kagoshima Space Center, Japan, toward a touchdown on Nereus in September 2003. A NASA-provided miniature robotic rover will conduct measurements on the rocky surface.
Asteroid samples will be returned to Earth by MUSES-C via a parachute-borne recovery capsule in January 2006, just weeks after a NASA mission named Stardust is expected to return collected comet dust samples to Earth.
Nereus is a small, near-Earth asteroid roughly one mile in diameter. It was discovered in 1982. At its closest point to the Sun, its orbit takes it just inside the orbit of the Earth.
Professor Binzel's advance measurements of Nereus are especially important because of the asteroid's small size, irregular shape and weak surface gravity. Getting MUSES-C to the right place at the right time "is a very difficult thing to do," he said. "We have to navigate very carefully. We need to get as much information as we can as early as we can about the target."
"This ambitious mission is an opportunity for two space-faring nations to combine their expertise and achieve something truly fantastic," said Dr. Jurgen Rahe, director of Solar System Exploration at NASA Headquarters. "The rover will be the smallest ever flown in space. With a successful mission, we will have the first direct insight into the composition of the materials that helped form the rocky inner planets more than four billion years ago."
With a mass of less than 2.2 pounds, the asteroid rover technology experiment is a direct descendant of the technology used to build the Sojourner rover due to land on Mars with the Mars Pathfinder lander on July 4. The rover will carry two science instruments: a visible imaging camera and a near-infrared point spectrometer. It will be designed and built by NASA's Jet Propulsion Laboratory in Pasadena, CA.
NASA and ISAS will cooperate on several aspects of the mission, including mission support and scientific analysis. Dr. Atsuhiro Nishida, director general of ISAS, and Dr. Wesley T. Huntress Jr., NASA associate administrator for space science, signed a summary of discussions outlining the cooperation on MUSES-C during a May 2 meeting in Washington. This is one in a series of NASA missions focused on asteroids.
A version of this article appeared in MIT Tech Talk on June 4, 1997.