Astro-2 Public Affairs Status Report #1
6:00 a.m. CST (0/5:22 MET), March 2, 1995
Spacelab Mission Operations Control
Marshall Space Flight Center
Huntsville, Ala.


	Astronomers aboard the Space Shuttle Endeavour are preparing the 
Astro-2 observatory for a unique exploration of the ultraviolet universe, 
following a dramatic nighttime launch at 12:38 a.m. CST.

	Payload Commander Tammy Jernigan completed initial activation
of the Spacelab pallet systems just before 4 a.m.  She then began
activating the Spacelab Instrument Pointing System, on which the
observatory's three telescopes are mounted.  At 5:47 a.m., she raised
it upright in the Shuttle cargo bay to face the heavens.  Astronomers
will use the pointing system to precisely track the stars and galaxies
they study during the nearly 16-day mission.

	Payload controllers and science teams at NASA's Spacelab
Mission Operations Control center in Huntsville watched closely as
Payload Specialist Sam Durrance supplied power from the Spacelab to
the telescopes shortly after 4 a.m., then started step-by-step
procedures to activate the individual instruments.  Telescope
activation will continue until after the end of his shift at about
10:30 this morning.  Durrance, an astronomer from The Johns Hopkins
University in Baltimore, Md., is a veteran of the first Astro mission
in December 1990, which was the maiden Shuttle flight for all three
Astro telescopes.

	Each of the telescopes provides unique insights into radiation
emitted by stars and galaxies in ultraviolet wavelengths -- a universe
that is strikingly different than that which is revealed in visible
light.

	The Hopkins Ultraviolet Telescope, from Johns Hopkins
University, conducts spectroscopy in the far ultraviolet portion of
the spectrum to identify elements present and processes taking place
in celestial objects.

	The Ultraviolet Imaging Telescope, provided by NASA's Goddard
Space Flight Center in Greenbelt, Md., takes wide-field photographs of
objects in ultraviolet light, recording the images on film for
processing back on Earth.

	The Wisconsin Ultraviolet Photo-Polarimeter Experiment,
developed by the University of Wisconsin at Madison, measures the
intensity of ultraviolet light and its degree of polarization,
revealing clues about the geometry of stars or the composition and
structure of the interstellar medium they illuminate.
	
	Because most ultraviolet radiation is absorbed by Earth's
atmosphere, it cannot be studied from the ground.  The far and extreme
ultraviolet region of the spectrum was largely unexplored before
Astro-1, but knowledge of all wavelengths is essential to obtain an
accurate picture of the universe.  Astro-2 will have almost twice the
duration of its predecessor, and a launch at a different time of year
allows the telescopes to view different portions of the sky.  The
mission promises to fill in large gaps in astronomers' understanding
of the universe and lay the foundations for more discovery in the
future.

	After fine-tuning of the Instrument Pointing System and
instrument activation are completed this afternoon, the crew will
focus and align the three telescopes for simultaneous, or joint,
observations.