Genesis Principal Investigator Donald Burnett was all smiles this past holiday season thanks to Johnson Space Center's (JSC) Curation team, delivering portions of the jolly ol' Sun for analysis here on Earth.
Burnett received several 5-7 mm-sized wafer fragments, as did Co-Investigators at JSC, early December 2004.
Co-Investigators at Washington University in St. Louis received a cut piece of the Polished Aluminum Collector on Jan. 4, 2005. This was the first delivery supporting the "early science return" activity that will establish solar isotopic and elemental abundances of noble gases.
Burnett et al. will characterize the solar wind collector surface contamination, evaluate the effectiveness of existing cleaning techniques and identify new techniques.
Preliminary results indicate that surface contamination of the wafers will be manageable for many analytical techniques.
Characterization tools are Spectroscopic Ellipsometry at JSC, X-ray Photoelectron Spectroscopy (XPS) at the Jet Propulsion Laboratory and Secondary Ion Mass Spectrometry (SIMS) at Charles Evans Associates.
One encouraging side result of the SIMS analysis was the detection of implanted hydrogen, magnesium and iron in the collector materials.
Scientists at UC Berkeley are also working with Genesis flight samples, and science team members around the world are calibrating their equipment, in anticipation of the allocation of Genesis samples to the international community.
But despite the early science return objective, curation team members are deliberate and calculating with each decision regarding the samples, and are in, "no rush," as Project Scientist, Amy Jurewicz put it.
"The Genesis team still fully expects to meet all of its science goals, but that will only happen if the samples are cleaned, stored and analyzed properly, said Jurewicz. "Clearly this effort is a work in progress and will be for some time."
Meticulous information on the contamination of the spacecraft is being compiled by a collaboration of JSC's curatorial staff, Genesis team members and NASA's sample Curation and Analysis Planning Team for Extraterrestrial Materials (CAPTEM). This collaboration is also experimenting with cleaning techniques and planning for the future.
Detailed preliminary reports from these studies are expected to be presented to the scientific community, as well as the interested public this March, at the Lunar and Planetary Science Conference.
As for Genesis's spacecraft bus, the last day of commanding the spacecraft's primary mission was Dec. 2, 2004. Shortly after 1 p.m. the Genesis flight team sent commands to place the spacecraft into a hibernation mode. While in this "safe" mode, it will continue transmitting health and safety information, autonomously pointing its solar arrays toward the Sun.
The spacecraft is on a trajectory to leave the Earth-Moon Lagrange 1 (L1) vicinity going into a long-term heliocentric orbit around the Sun, with Earth trailing behind. The craft will be able to be maneuvered to stay in the Earth-Moon vicinity up through Feb. 1, 2005.
Although the Genesis flight team bade farewell to its spacecraft, it will not be forgotten. On a more personal note, Burnett summed up the team's feelings about Genesis when he said, "It's always hard to say goodbye to a good friend."
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