Purdue Science and Health Briefs
Purdue Science and Health Briefs
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August 1998
Martian meteorites provide glimpse inside Red PlanetWEST LAFAYETTE, Ind. -- Though scientists can't trace Martian meteorites back to their specific sites on the Red Planet, a Purdue University study shows that the travelers contain more chemical clues to the location and history of their native neighborhoods than originally expected.Michael Lipschutz, professor of chemistry, analyzed the trace element content of the 12 meteorites that are known to have originated from Mars and found that the rocky fragments came from six different regions below the surface of the planet. He also found that each of the six regions operated as a "closed system," blocking the transfer of materials such as dust and vapor between regions. "Since even vapor transfer did not occur between the regions, the composition of each Martian meteorite can be considered an accurate reflection of its source region, and therefore can provide detailed information on each region's location and history," Lipschutz says. The study was published in the July issue of Meteoritics and Planetary Science, which focused on the Martian meteorites. Lipschutz also wrote the chapter on meteorites for the 40-chapter Encyclopedia of the Solar System, which will be available in August. Based on concentrations of 15 volatile trace elements, which are the chemical elements most likely to condense last as the planet solidified from a cloud of dust and gas, Lipschutz was able to divide the meteorites into six major groups from as many different parent regions. He then compared the groupings to previous studies that had divided the meteorites into six classifications based upon other chemical contents and markers. Because the groupings were virtually identical -- a finding that indicated that the trace elements were intact and had escaped contamination from outside influences -- Lipschutz says the volatile chemical contents of the meteorites can serve as reliable markers to assess information on their thermal histories. "These rocks provide samples from and glimpses into six chambers within the Martian mantle," Lipschutz says. "Each of the 12 Martian meteorites appears to have crystallized in a location deep within the planet, and was excavated only when its chamber was opened by an impact." Lipschutz says it is unusual to find samples where the chemical markers are so well preserved. "The amazing thing is that whatever chemical and geological events Mars experienced through time, all of the elements -- volatile or not -- were able to remain intact," Lipschutz says. "This is unlike the situation in other extraterrestrial bodies, such as the Moon and many asteroids, where heating caused by events such as the shock of an impact can vaporize the volatile elements and destroy evidence of past events." Further studies may help pinpoint the location of each of the regions, and could shed light on Mars' geological history, Lipschutz says. His study was funded by the National Aeronautics and Space Administration's Cosmochemistry program. CONTACT: Lipschutz, (765) 494-5326 or (765) 494-5204; e-mail rnapuml@vm.cc.purdue.edu
Student looks forward to cool research opportunityNOTE TO JOURNALISTS: A head-and-shoulders color photograph of Benjamin Hasse is available from the Purdue News Service. WEST LAFAYETTE, Ind. -- A forestry major from Purdue University will spend the first semester of his junior year on a frozen continent completely devoid of trees. The National Science Foundation and the Boy Scouts of America have chosen Benjamin Hasse of Kingsford, Mich., as their candidate to spend next fall helping Antarctic researchers. "No obvious connection to my major -- no trees in the Antarctic! But I should learn more about how I'll function in a harsh environment," Hasse said. Harsh is an understatement for the Antarctic, where the world's record low temperature was recorded -- minus 128.6 degrees Fahrenheit -- and wind gusts can reach nearly 200 miles per hour. Every three years the National Science Foundation permits the Boy Scouts to designate an Eagle Scout to join its scientists, helping to fulfill the U.S. government agency's goal of providing students with research opportunities outside the classroom. From October through mid-January, Hasse will travel to different research stations on the frozen continent. He becomes the ninth Eagle Scout chosen for the Antarctic Scout Program. Paul Siple was the first, traveling with Adm. Richard Byrd's 1928 expedition at the explorer's request. Siple eventually became a researcher and one of Byrd's right-hand men. "We chose Ben from 112 candidates and four finalists -- all outstanding students with proven scouting backgrounds," said John Alline, national director of Boy Scout training. "His natural curiosity about science and strong communication skills made him a standout. We also were impressed with his continuing service at a Lafayette homeless shelter." Hasse said, "I don't have any specific scientific skills, but I'm told an extra pair of hands will be useful. I would be happy to dig holes in the snow or pull sleds myself just for the opportunity and adventure." Hasse, who is majoring in Spanish along with forestry, has maintained a perfect 4.0 cumulative grade point average during his two years at Purdue, and he is a Purdue Beering Scholar. The Steven C. Beering Scholarships and Fellowships were created in 1986 by Purdue President Beering to attract students of the highest caliber. The award covers all college expenses, including fees and tuition, room and board, books and spending money. Undergraduate recipients who maintain the required standards hold the Beering Scholarship throughout their time at Purdue and may convert it to a fellowship to pursue master's and doctoral degrees at Purdue. CONTACTS: Hasse, (906) 774-6820; e-mail: bjhasse@expert.cc.purdue.edu; and John Alline, (972) 580-7835; e-mail: jalline@netbsa.org
Composting livestock waste provides benefitsWEST LAFAYETTE, Ind. -- Purdue University researchers have found that composting waste from livestock operations can be an efficient way to manage the waste with less cost. Composting also virtually eliminates smells and runoff problems.
"Before this we had to do a daily scrape and haul," Hawkins says. "In all weather, 365 days of the year, we had to spread the manure on the fields. It was hard to find good people to do it, it was hard on the equipment, and the constant driving across the fields was causing soil compaction. "We've gone from spreading manure on a daily basis to spreading compost five or six days a year." Composting is also safer for the environment than stockpiling manure, according to Hawkins. "Stockpiled manure is not environmentally stable, which poses some safety concerns," he says. "There is the possibility of leachate moving off-site and into nearby streams. If the manure is spread on fields during the winter, it may not decompose, and then it can run off the fields into streams when it rains. Composting allows the manure to stay in a managed holding pattern until the time is right to apply it." Many livestock farms use lagoons to handle manure, but these have a strong odor and can become clogged with the manure solids. "It just turns to a big sludge pit," Hawkins says. Even if the lagoon doesn't become filled with solids, it still requires the producer to stir it and to periodically pump it out, he says. According to Hawkins, composting manure solids offers these advantages for the medium to large livestock producer:
Hawkins also suggests that the finished compost also could be sold to landscaping contractors or given away to neighbors in a suburban setting to build good community relations. CONTACT: Hawkins, (765) 494-8367; e-mail, seh@aes.purdue.edu
Compiled by Amanda Siegfried, (765) 494-4709; e-mail, amanda_siegfried@purdue.edu Purdue News Service: (765) 494-2096; e-mail, purduenews@purdue.edu
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