EVIDENCE OF ACCRETION-GENERATED X-RAYS IN THE YOUNG ...

3.2 The Chandra X-ray Observatory
Launched from the Space Shuttle Columbia on July 23, 1999, the 45-foot long
Chandra X-ray Observatory (CXO) is an orbiting X-ray telescope and the third of
NASA’s four “Great Observatories.” CXO (Fig. 9) is named after Subrahmanyan
Chandrasekhar, the Nobel prize-winning physicist most noted for first calculating the
mass limit of a white dwarf. Chandra’s rather eccentric orbit takes it into a high Earth
orbit, putting it above the Van Allen belts for most of its 64.3-hour orbital period and
allowing for roughly 55 hours of continuous observation time. The Chandra X-ray
Observatory is unique in that it has the highest spectral and spatial resolutions thus
far of any orbiting X-ray observatory – up to 0.012˚A (or 1 eV) at Full Width Half
Maximum (FWHM) and up to to 0.5 00 at FWHM, respectively. Chandra’s spectral
range is 0.3–10 keV, and though other X-ray observatories such as XMM-Newton
provide a wider calibrated spectral energy range, they have a lower spectral resolution.
The Chandra X-ray Observatory has a suite of instruments and components, including
the High Resolution Mirror Assembly (HRMA), the High Resolution Camera (HRC),
the Advanced CCD Imaging Spectrometer (ACIS), and the Low- and High-Energy
Transmission Gratings (LETG/HETG), which allow it to make a number of various
types of X-ray observations.
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