ANN ARBOR—A University of Michigan space instrument will take the first direct measurements of the planet Mercury’s wispy atmosphere and space environment on Jan. 14, when NASA’s MESSENGER spacecraft does its initial flyby of the closest world to the sun.

No spacecraft has visited Mercury since the Mariner 10 in 1975 mapped parts of the planet. This is the first of three flybys scheduled for the next two years, which will bring MESSENGER progressively closer to Mercury until it can enter orbit in 2011.

The Fast Imaging Plasma Spectrometer (FIPS) instrument onboard MESSENGER, designed and built at U-M, will take measurements to determine what Mercury’s atmosphere is composed of and how the planet interacts with its space environment. The planet’s magnetic field and its proximity to the sun provide an interesting test-case for interaction of the solar wind with terrestrial planets.

“Mercury’s space environment is at the extreme,” said Thomas Zurbuchen, FIPS instrument project leader and a professor in the department of Atmospheric, Oceanic and Space Science. “It’s Earth-like because it does have a magnetosphere, although a very weak one. But the planet is in the most violent part of the solar system. Radiation from the sun in the form of heat and particle radiation from the solar wind can impact Mercury.”

On average, Mercury is just 36 million miles from the sun?about two-thirds closer than the Earth. And Mercury is the smallest planet in the solar system at just 3,000 miles across at its equator.

On Earth, the magnetosphere protects us from the sun’s heat and other forms of radiation including the charged particles in the solar wind. FIPS will help scientists figure out how Mercury’s magnetosphere works.

Scientists believe Mercury’s exceedingly thin atmosphere includes sodium, oxygen and potassium. Zurbuchen believes there’s more to it.

“The vast majority of the components of Mercury’s atmosphere have never been directly measured,” he said.

Zurbuchen can be reached on his cell phone at (734) 502-5500.

Other members of the FIPS team are:

Jim Raines, research computer specialist, (734) 763-6223

George Gloeckler, research professor, (734) 615-3583

Robert Lundgren, senior engineer, (734) 936-7262

Michigan Engineering:

The University of Michigan College of Engineering is ranked among the top engineering schools in the country. Michigan Engineering boasts one of the largest engineering research budgets of any public university, at more than $130 million annually. Michigan Engineering is home to 11 academic departments and a National Science Foundation Engineering Research Center. The College plays a leading role in the Michigan Memorial Phoenix Energy Institute and the Graham Environmental Sustainability Institute. Within the College, there is a special emphasis on research in three emerging areas: nanotechnology and integrated microsystems; cellular and molecular biotechnology; and information technology. Michigan Engineering is raising $300 million for capital projects and program support in these and other areas to continue fostering breakthrough scholarly advances, an unparalleled scope of student opportunities and contributions that improve the quality of life on an international scale.
For more information on Zurbuchen: http://www.ns.umich.edu/htdocs/public/experts/ExpDisplay.php?ExpID=1252

http://aoss.engin.umich.edu/people/thomasz

NASA press release: http://messenger.jhuapl.edu/news_room/status_report_01_10_08.html

The U-M Solar and Heliospheric Research Group: http://solar-heliospheric.engin.umich.edu/messenger/

More spacecraft with U-M instruments: http://aoss.engin.umich.edu/pages/research/space_missions

U-M Solar and Heliospheric Research GroupMore spacecraft with U-M instrumentsNASA press releaseThomas Zurbuchen