[Mb-civic] A washingtonpost.com article from: swiggard@comcast.net

Mon May 2 04:06:17 PDT 2005

You have been sent this message from swiggard at comcast.net as a courtesy of washingtonpost.com 

 Teams Pry Secrets From What's Left of Genesis

 By Guy Gugliotta

  HOUSTON -- Stunt helicopters were supposed to pluck the Genesis space capsule gently from the sky as it parachuted earthward, but the hoped-for Hollywood thriller turned into a sour farce when the parachutes failed to open and it plummeted to the ground like a B-movie flying saucer.

 That was Sept. 8, 2004, the beginning of what Eileen Stansbery called "a stressful, tension-filled time" for a NASA-led team of forensic specialists who spent 26 days in a makeshift clean room trying to salvage a priceless treasure -- particles from the sun like those that gave birth to the solar system 4.5 billion years ago.

 Eight months later, however, the Genesis project is "open for business," said Stansbery, assistant director of astromaterials research and exploration science at Houston's Johnson Space Center. Samples are available to researchers for study, and it appears the project will probably realize all the science it hoped for, although "maybe not with the same precision" and not "as quickly as we originally wanted," she said.

 Some research is already underway. A team at Washington University in St. Louis anticipates little problem gleaning samples of noble gases -- helium, neon, argon, xenon and krypton that came from the sun -- from the shiny surface of Genesis's aluminum heat shield.

 At the University of California at Berkeley, however, cosmochemist Kunihiko Nishiizumi is seeking suggestions as he struggles to figure out how to straighten sheets of crumpled platinum foil that hold traces of radioactive isotopes of beryllium, aluminum, manganese and other elements.

 Genesis was launched Aug. 8, 2001, and eventually spent 850 days collecting particles of the solar wind by exposing a variety of surfaces to the sun's rays. Over time, the heat shield, the foil and hundreds of four-inch-wide ceramic "wafers" were impregnated with samples of all the elements and isotopes spewed by the sun -- a benchmark for studying how the solar system's chemistry evolved on Earth and elsewhere.

 The particles were precious -- the equivalent of a few grains of salt in all -- and NASA had devised the midair helicopter recovery to eliminate the jolt of a touchdown and to keep the fragile hexagonal wafers intact. Instead, the capsule crashed into Utah's Dugway Proving Ground at 193 mph, split open and came to rest waist-deep in a salty mud flat.

 One silicon-on-sapphire wafer was intact, two others were broken in two, and two more were in "a few large pieces," Stansbery said. But the 301 ceramic hexagons and half-hexagons that began the trip were in tens of thousands of pieces, most of them an inch in diameter or smaller. Virtually all were contaminated with various combinations of dust, mud, salt and mashed-up pieces of spacecraft.

 NASA's Dugway team had planned for various contingencies. This one was worse than the one they had called "hole in the side" of the capsule, but not as bad as "shards across the desert."

 Two tasks were crucial: map the location of the pieces inside the container so forensic specialists could identify which wafers they came from; and use a variety of packaging methods, so if one piece of wafer was ruined in transit, others would survive.

 "We had field kits -- five-gallon buckets, trowels, zip-lock bags, cameras," Stansbery said in an interview. The team worked in a temporary clean room at Dugway, packed the shards in one- and two-inch vials, wafer containers, plastic and glass jars, tissue culture dishes, aluminum foil wrappers and 96-hole sample trays.

 On Oct. 4, a NASA plane flew the salvaged material to the Johnson Space Center, where it is stored in low-humidity nitrogen gas in a repository below the Lunar Sample Laboratory Facility that houses moon rocks from the Apollo era.

 Once locked away, the Genesis team began researching decontamination methods and offering researchers a menu of possibilities, Stansbery said. "One cleaning method may work if you want to do one kind of analysis, but you would need to do it differently for another kind of analysis."

 On March 1, her team officially offered samples to waiting scientists. "We are not doing anything until people ask," Stansbery said. "If they want to clean it, we'll give them a recipe. If they want us to do it, we'll do it, but they'll have to wait longer."

 Cleaning can be easy or difficult, and perhaps impossible in some cases depending on what contaminant is being removed -- dust is relatively easy, mud is hard and salt is nasty -- and how it is being done. The team has software that will find and remember the locations of dust particles on a shard as it is viewed on a microscope, enabling researchers to ignore bad spots.

 "An important thing to understand is that even independent of the crash, this is really difficult analytical chemistry," said University of Chicago cosmochemist Andrew Davis, who chairs the NASA oversight committee that monitors the care of the samples and evaluates researchers' requests. "Most of the people with serious interest have been thinking about it for years."

 And developing their own techniques. At the University of Minnesota, researchers plan to expose gold foil to mercury in a vacuum, a process that will release nitrogen deposited by the solar wind. Contamination does not affect this chemical reaction.

 Also facing a relatively easy task are Washington University researchers Charles Hohenberg and Alex Meshik, who designed a special laser system to peel the surface from the aluminum heat shield layer by layer so they can read the levels of noble gas from the vapor.

 "It's like removing a tattoo," Meshik said in a telephone interview. "We have some mud spots, but we just avoid them. We have plenty of clean surface." Meshik said the team has already successfully tested the technique.

 Berkeley's Nishiizumi, by contrast, has a daunting challenge. He needed a large surface to capture his radionuclides, and Genesis had provided him with 1,240 square centimeters of platinum foil covered with a thin film of molybdenum. The idea is to dissolve the molybdenum, extract the radionuclides and analyze them with an accelerator mass spectrometer.

 "The major problem is that most of the foil is twisted and hard to open," Nishiizumi said in a telephone interview. He cannot touch the molybdenum surface, and so must flatten the foil from the back, a problem made even more difficult because platinum foil becomes brittle after it is crumpled.

 "I've talked to materials scientists and many museum people to get ideas," Nishiizumi said. "I can't heat it so I'm going to have to develop a mechanical method. I'll probably have to do it by hand -- with my fingers."

 Would you like to send this article to a friend? Go to 
http://www.washingtonpost.com/ac2/wp-dyn/emailafriend?contentId=AR2005050100733&sent=no&referrer=emailarticle

Visit washingtonpost.com today for the latest in:

News - http://www.washingtonpost.com/?referrer=emailarticle

Politics - http://www.washingtonpost.com/wp-dyn/politics/?referrer=emailarticle

Sports - http://www.washingtonpost.com/wp-dyn/sports/?referrer=emailarticle

Entertainment - http://www.washingtonpost.com/wp-dyn/artsandliving/entertainmentguide/?referrer=emailarticle

Travel - http://www.washingtonpost.com/wp-dyn/travel/?referrer=emailarticle

Technology - http://www.washingtonpost.com/wp-dyn/technology/?referrer=emailarticle

Want the latest news in your inbox? Check out washingtonpost.com's e-mail newsletters:

http://www.washingtonpost.com/ac2/wp-dyn?node=admin/email&referrer=emailarticle

Washingtonpost.Newsweek Interactive
c/o E-mail Customer Care
1515 N. Courthouse Road
Arlington, VA 22201 

© 2004 The Washington Post Company