... 295 Astronomical Data Analysis Software and Systems XII, eds. H. E. Payne, R. I. Jedrzejewski, & R. N. Hook (San Francisco: ASP), 411 . ... Observations by the Chandra X-Ray Observatory are made in a coordinate frame that is essentially fixed. Most objects observed with Chandra, such as supernova remnants, quasars, or pulsars, are at infinity for all practical purposes and the observations produce sharp, focused images. ... Figure 2: Jupiter in ICRS and Object Centered coordinates . ... 2002). ...