University of Colorado at Boulder space physicist Daniel Baker will give a talk on Monday, Jan. 28, about the mysteries of the tiny planet Mercury and his involvement in NASA's upcoming mission there.
Baker, who is director of the Laboratory for Atmospheric and Space Physics, or LASP, will speak from 4 p.m. to 5 p.m. in the JILA auditorium, located on the lower level of the JILA tower in the CU-Boulder Duane Physics building.
The talk is free and open to the public. Parking is available in the Euclid Avenue Autopark and along Colorado Avenue, near Folsom Street.
NASA's Mariner 10 spacecraft flew past Mercury in 1974 and again in 1975, intriguing scientists with a number of tantalizing findings about the little planet, according to Baker. Mercury has held onto its secrets, however, since no missions have visited the planet in more than 25 years.
That soon will change, he said, as several craft are planned to head toward the closest planet to the sun in the next decade. The first of these planned missions is the NASA spacecraft dubbed the Mercury Surface Space Environment Geochemistry and Ranging mission or MESSENGER. MESSENGER is part of NASA's Discovery program, which develops frequent, science-packed missions for less than $300 million each.
Slated for launch in 2004, the mission will study Mercury's surface structure and composition, interior structure and magnetic field, and its atmospheric and magnetospheric composition.
As a co-investigator on MESSENGER, Baker is particularly interested in Mariner 10's puzzling finding that Mercury possesses a magnetic field not unlike that of Earth.
"Because of its small size, Mercury was thought to have radiated away most of its interior heat long ago," said Baker. "That it has a magnetic field suggests the planet's interior did not cool and solidify, but instead churns away to this day - creating a magnetic dynamo effect, similar to what happens within the Earth."
Mariner 10 also detected intense particle bursts and magnetic field disturbances, called magnetospheric substorms at Mercury, he said.
"On Earth, we think the ionosphere plays a key role in creating this phenomenon," said Baker. "MESSENGER will help us understand how it could occur on a planet without an ionosphere." The ionosphere is the outer part of Earth's atmosphere, beginning about 34 miles above the planet.
Included in MESSENGER's suite of instruments is the Mercury Atmospheric and Surface Composition Spectrometer, or MASCS, which will be designed, built and operated by LASP. LASP Research Associate William McClintock will oversee the design and construction of the $9.5 million instrument.
The mission also will carry an instrument to search for signs of water ice, which some scientists believe may exist in permanently shadowed craters at the planet's poles.
MESSENGER is important not only in terms of understanding Mercury's history, said Baker, but also for constructing future models of how terrestrial, or Earth-like, planets form, and understanding the formation of our solar system as a whole.
MESSENGER is a collaboration of 11 different institutions and is managed by the Applied Physics Laboratory at the Johns Hopkins University.
LASP has been an active participant in the U.S. space program since the early 1950s. Funded primarily by NASA , members of LASP conduct fundamental research in the atmospheric and planetary sciences, develop space instrumentation and create computer information systems for space operations.