India's first dedicated astronomy satellite, scheduled for launch on board the PSLV in mid 2010, Astrosat will monitor the X-ray sky for new transients, among other scientific focuses.

Both the Puppis and Vela remnants are among the largest and brightest features in the X-ray sky.

Suppose you compare the X-ray sky with observations taken through radio telescopes.

Rosat was launched in 1990 to survey the X-ray sky.

The first map of the X-ray sky as measured with the imaging X-ray telescope on board the ROSAT satellite (1993)

It will monitor several hundred X-ray sources on a daily basis, and will be the first instrument to monitor the complete X-ray sky simultaneously.

Puppis A is one of the brightest X-ray sources in the X-ray sky.

HEAO-1 scanned the X-ray sky over 0.2 keV - 10 MeV.

During outburst, a bright SXT is the brightest object in the X-ray sky, and the apparent magnitude is about 12.

Image credit: ISAS/JAXA The Suzaku spacecraft will help us to learn in more detail about the X-ray sky.