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<a href="../curator.htm" TARGET="_top"><img src=seh_banner.gif alt="Space Exposed Hardware" width=600 height=81 border=0></a>
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<li><A HREF = "samreq.htm" TARGET="_top"><B>How to Request Samples</B></A>
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<li><A HREF = "courier/courier.htm" TARGET="_top"><B>Dust Courier</B></A>
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<li><A HREF = "http://sn-charon.jsc.nasa.gov/dbsearch/ldef/searchmenu.htm" TARGET="_top"><B>LDEF Database Search</B></A>
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<li><A HREF = "curation.htm" TARGET="_top"><font size=4><B>Space Hardware Sample Curation & Availability</B></font></A>
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<li><A HREF = "ldps.htm" TARGET="_top"><B>LDEF Surfaces</B></A>
<li><A HREF = "ldcores.htm" TARGET="_top"><B>LDEF Cores</B></A>
<li><A HREF = "eureca.htm" TARGET="_top"><B>EURECA Satellite</B></A>
<li><A HREF = "smax.htm" TARGET="_top"><B>Solar Maxiumum Satellite</B></A>
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<li><A HREF = "ldpis.htm" TARGET="_top"><B>Investigators Who Have Received LDEF Samples to Date</B></A>
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<li><A HREF = "ldef/ldef.htm" TARGET="_top"><B>LDEF Meteoroid & Debris Special Investigation Group</B></A>
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<li><A HREF = "phonenos.htm" TARGET="_top"><B>Space Exposed Hardware Contact</B></A>
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<td><A HREF = "ldef/ldef.htm" TARGET="_top"><img src=ldef.gif width=295 height=222 alt="LDEF Retrieval" align=left hspace=20 vspace=5 BORDER=0></A></td>
<td><A HREF = "ldef/ldef.htm" TARGET="_top"><img src="impacts.gif" width=202 height=232 alt="Impacts on LDEF" align=right hspace=20 vspace=5 BORDER=0></A></td>
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<font size=+3>W</font>hen Earth-made articles are exposed to space, they experience erosion when hit by high-velocity dust grains and by reaction with atomic oxygen. Since 1970 JSC has curated pieces of space-exposed surfaces containing impacts by dust particles, such as pieces of the Surveyor III Spacecraft (recovered from the lunar surface), LDEF (Long Duration Exposure Facility) and Solar Max satellites, and European Recoverable Carrier (EuReCa). Over 8000 individual impact features, usually very small craters, are being studied.
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The size of the small craters and the composition of the dust-grain impactor residues yield important information about the population of planetary and human-made debris in low-Earth orbit. Information retrieved from the space-exposed surfaces mutually complements information from stratospheric dust collection.
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