SOFIA, short for Stratospheric Observatory for Infrared Astronomy,
is a 2.7m telescope flying on a Boeing 747SP at altitudes of 12-14km,
to detect and study mid- and far-infrared radiation that is blocked
by water vapor in the earth's atmosphere and cannot reach the
ground. It is the successor to the Kuiper Airborne Observatory (1974-1995)
and currently the only access to and platform for astronomical observations
in the far-infrared (30-300 microns), except for balloon-borne telescopes.
SOFIA normally flies out of California, but once a year also
deploys to the Southern Hemisphere (usually to Christchurch,
New Zealand), benefitting from the excellent wintertime
stratospheric conditions to study the rich southern skies.
Although a bilateral project (80:20)
between USA (NASA/USRA) and Germany (DLR/DSI), it is open for
proposals from the world-wide astronomical community at large.
It addresses many science questions that ESA's successful but
now extinct Herschel Observatory has left unanswered and
offers observational opportunities similar to and beyond Herschel.
SOFIA also has many synergies with ALMA and APEX, as well as IRAM
and other submm and radio telescopes.
In part I of this SOFIA lecture, I will introduce the observatory
in general, the plane, the telescope, the mode of operation, and
in particular the current and future instrumentation.
In part II (later this week), I will present a glimpse of SOFIA science
results. I will also address its future ISM and star formation potential.
