  Energetic young pulsars and expanding blast waves (supernova remnants, SNRs)
are the most visible remains after massive stars, ending their lives, explode
in core-collapse supernovae. The Fermi Gamma-Ray Space Telescope has unveiled a
radio quiet pulsar located near the center of the compact synchrotron nebula
inside the supernova remnant CTA 1. The pulsar, discovered through its
gamma-ray pulsations, has a period of 316.86 ms, a period derivative of 3.614 x
10-13 s s-1 . Its characteristic age of 104 years is comparable to that
estimated for the SNR. It is conjectured that most unidentified Galactic gamma
ray sources associated with star-forming regions and SNRs are such young
pulsars.
