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Last modified: 21 November 2006

URL: http://cxc.harvard.edu/ciao3.4/bugs/sso_freeze.html
Hardcopy (PDF): A4 | Letter

Bugs: sso_freeze


Caveats

  1. Use linear output object-centered coordinates when combining several ObsIDs widely spaced in time.

  2. sso_freeze does not account for SSO rotation or large changes in the sun illumination angle of the SSO.


Caveats

  1. Use linear output object-centered coordinates when combining several ObsIDs widely spaced in time.

    It is recommended that linear output object-centered coordinates be chosen instead of angular when combining several ObsIDs widely spaced in time. This will avoid the problem of different apparent angular sizes in the object, which occurs when the Chandra-to-object distance has changed significantly.

  2. sso_freeze does not account for SSO rotation or large changes in the sun illumination angle of the SSO.

    Although X-rays emitted by the SSO may be affected by either SSO rotation or large changes in the sun illumination angle of the SSO, neither effect is taken into account by sso_freeze.

Hardcopy (PDF): A4 | Letter
Last modified: 21 November 2006


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