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  <title>Chandra X-ray Observatory Data Archive</title>
  <shortName>CDA</shortName>
  <identifier>ivo://cxc.harvard.edu/cda.siap</identifier>
  <curation>
    <publisher ivo-id="ivo://cxc.harvard.edu/cxo">Chandra X-ray Observatory</publisher>
    <creator>
      <name>Chandra X-ray Center</name>
    </creator>
    <contact>
      <name>Chandra Data Archive, Chandra X-ray Center</name>
      <address>60 Garden Street MS 67, Cambridge, MA 02138, USA</address>
      <email>archelp@head.cfa.harvard.edu</email>
    </contact>
  </curation>
  <content>
    <subject>X-ray astronomy</subject>
    <subject>galaxies</subject>
    <subject>quasars</subject>
    <subject>stars</subject>
    <subject>X-ray</subject>
    <subject>photometry</subject>
    <subject>spectroscopy</subject>
    <subject>variability</subject>
    <description>
The Chandra X-ray Observatory is the U.S. follow-on to the Einstein
Observatory. Chandra was formerly known as AXAF, the Advanced X-ray
Astrophysics Facility, but renamed by NASA in December, 1998.
Originally three instruments and a high-resolution mirror carried in
one spacecraft, the project was reworked in 1992 and 1993. The Chandra
spacecraft carries a high resolution mirror, two imaging detectors,
and two sets of transmission gratings. Important Chandra features are:
an order of magnitude improvement in spatial resolution, good
sensitivity from 0.1 to 10 keV, and the capability for high spectral
resolution observations over most of this range.
</description>
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    <type>Archive</type>
    <contentLevel>Research</contentLevel>
    <contentLevel>University</contentLevel>
    <contentLevel>Community College</contentLevel>
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        <lat>72.17</lat>
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    <waveband>X-ray</waveband>
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