50 years of X-ray astronomy
In June 2012, X-ray astronomy celebrates its 50th
following the discovery of the first extra-solar cosmic X-ray source
in 1962. The XMM-Newton team recognizes the rich heritage from which
XMM-Newton has grown and joins astronomers all over the world
in the celebration.
Also XMM-Newton has observed the first cosmic X-ray source different than
the Sun, Scorpio X-1, which was discovered in June 1962: This
figure shows the high-resolution soft X-ray spectrum of Sco X-1,
taken with the RGS instrument.
The diffuse X-ray background discovered in 1962 together with
Sco X-1, is now recognized to be produced by individual objects,
mainly distant active galaxies, as shown, e.g., by this XMM-Newton
EPIC image of the Lockman Hole.