"THE ORIGIN OF GALACTIC COSMIC RAYS: NEW RESULTS FROM
THE RUSSIAN SPACE STATION"
Interstellar space is filled with a "gas" of relativistic
nuclei and electrons called the Galactic Cosmic Rays (GCRs). GCRs
play an important role in the dynamics of matter and magnetic fields in
the interstellar medium, and probably even play an important role in star
formation. In spite of their importance, and despite much recent
progress, the origin of GCRs remains mysterious. We stand, however, on
the threshold of solving this long-standing puzzle. The abundance patterns
of the elements in the GCRs provide the key because they are the fingerprints
of GCR origin. I will describe the current state of our understanding,
report on recent measurements from the Trek instrument which was mounted
onboard Mir, and describe a new instrument, ECCO, which will measure the
age of ultraheavy GCR nuclei for the first time using Th/U/Pu/Cm dating.
ECCO, along with a complementary instrument called ENTICE, comprise a new
mission, the Heavy Nuclei eXplorer (HNX), which will measure the GCR abundance
of every individual element in the periodic table from neon through curium
and perhaps beyond. HNX was recently selected for Phase A study under
the SMEX program.