  Gamma-ray lines from radioactive isotopes, ejected into interstellar space by
cosmic nucleosynthesis events, are observed with new space telescopes. The
Compton Observatory had provided a sky survey for the isotopes 56Co, 22Na,
44Ti, and 26Al, detecting supernova radioactivity and the diffuse glow of
long-lived radioactivity from massive stars in the Galaxy. High-resolution
spectroscopy is now being exploited with Ge detectors: Since 2002, with ESA's
INTEGRAL satellite and the RHESSI solar imager two space-based Ge-gamma-ray
telescopes are in operation, measuring Doppler broadenings and line shape
details of cosmic gamma-ray lines. First year's results include a detection and
line shape measurement of annihilation emission, and 26Al emission from the
inner Galaxy and from the Cygnus region. 60Fe gamma-ray intensity is
surprisingly low; it may have been detected by RHESSI at 10% of the 26Al
brightness, yet is not seen by INTEGRAL. 44Ti emission from Cas A and SN1987A
is being studied; no other candidate young supernova remnants have been found
through 44Ti. 22Na from novae still is not seen.
