Mark Thiemens has spent an entire career studying and analyzing meteorites, chunks of space rock that survive the fiery plunge through Earth's atmosphere. Now he has an orbiting space rock -- an asteroid or "minor planet" -- to call his own. Thiemens, dean of the University of California at San Diego (UCSD) Div. of Physical Sciences, was recently informed that a minor planet orbiting the inner part of the main asteroid belt has been designated (7004) Markthiemens in honor of his work with meteorites.Mark Thiemens with meteorite. (Photo: Carolyn Ebrahimi, UCSD) "As someone who has loved space and space science since I was a kid and who has spent a research career involved with space and rockets, this is a wonderful acknowledgment," said Thiemens, who is also professor of chemistry and biochemistry at UCSD. Brian Marsden, head of the minor planet center at the Harvard-Smithsonian Center for Astrophysics, the clearinghouse for naming Earth-orbiting bodies, said Thiemens' asteroid was discovered in 1979 in Australia but was given a numbered designation only a few years ago, when its orbit was confirmed. It was first spotted by Schelte J. Bus, II, an associate astronomer at the University of Hawaii at Manoa, who officially named it last week in honor of Thiemens. The asteroid has an orbit of 2.3 astronomical units, the mean distance from the Earth to sun, and extends almost to the orbit of Mars. The amount of light it reflects from its surface suggests it is less than 10 kilometers, about six miles, in diameter. Marsden said that of 134,000 asteroids that have been found by astronomers, only about 13,000, or about 10 percent, have thus far been named. The designation of (7004) Markthiemens is the second major scientific honor Thiemens has received this year. In April, he was one of three UCSD professors elected to the National Academy of Sciences, one of the highest honors bestowed on US scientists. The founder and director of UCSD's Center for Environmental Research and Training, Thiemens has done research on a wide variety of problems -- from ozone chemistry to global warming to questions about the prospect of life on Mars. His most recent work has focused on understanding climate change from chemical clues embedded in the ice at the South Pole. He has twice received the Alexander Von Humboldt awards and won the E.O. Lawrence Award from the US Department of Energy in 1998. In 2002, he was elected to the American Academy of Arts and Sciences. Thiemens received his undergraduate degree in chemistry at the University of Miami and his PhD in oceanography from Florida State University. Shortly after coming to UCSD in 1980 from his postdoctoral fellowship at the University of Chicago, he made discoveries that overturned conventional theories about the formation and evolution of the solar system. For more information, visit: www.ucsd.edu