"Interstellar Dust in the Heliosphere and in the Local Interstellar Cloud "

Eberhard Gruen
Max-Planck-Institute for Nuclear Physics
& Hawaii Institute of Geophysics & Planetology

Long studied classically through its extinction of starlight, the
interstellar dust has recently been measured directly by spacecraft.
Small dust particles enter the solar system with the neutral helium
stream and are detected when they impact spacecraft far outside the
orbit of Earth.  Larger particles (bigger than the 0.4 micron "cutoff"
in the classical distribution) are less well coupled to the gas flow
and enter isotropically. Interstellar meteors have also been detected
and several experiments are planned to capture interstellar dust and
return it to Earth for analysis.

While surely one of the more remarkable achievments of the past decade,
the new interstellar dust studies have taken place somewhat outside the
perceived boundaries of astronomy, and they are not well known to
many in our field.  This talk should help to correct this situation.