X-ray Astronomy - Stellar X-ray Astronomy

Stellar X-ray Astronomy

Stellar X-ray astronomy is said to have started on April 5, 1974, with the detection of X-rays from Capella. A rocket flight on that date briefly calibrated its attitude control system when a star sensor pointed the payload axis at Capella (α Aur). During this period, X-rays in the range 0.2–1.6 keV were detected by an X-ray reflector system co-aligned with the star sensor. The X-ray luminosity of L_x = 1031 erg·s−1 (1024 W) is four orders of magnitude above the Sun's X-ray luminosity.