Paula Cleggett-Haleim
Headquarters, Washington, D.C.                                                                         
March 18, 1991
(Phone:  202/453-8400)

Franklin O'Donnell
Jet Propulsion Laboratory, Pasadena, Calif.
(Phone:  818/354-5011)


RELEASE:  91-43

MANEUVER TO TARGET GALILEO FOR ASTEROID FLYBY


   NASA's Galileo spacecraft will execute a trajectory 
correction maneuver Wednesday, March 20, to help aim it for the 
first-ever flyby of an asteroid next October.

   In the maneuver Galileo will fire its small thrusters on and 
off during a period beginning at about 1 p.m. EST and concluding 
at about 4:30 p.m. EST.  The firings will result in a velocity 
change of about 5 miles per hour.

   The maneuver, together with three more planned in July and 
October, will shape Galileo's flight path for its flyby of Gaspra 
in the main asteroid belt on Oct. 29.

   Galileo will be the first spacecraft to fly by an asteroid 
when it approaches within about 1,000 miles of the irregularly 
shaped, stony lump measuring nearly 15 miles across.  During the 
encounter, the spacecraft will photograph and collect a wide 
variety of scientific data on the asteroid.

   The spacecraft has an opportunity for another asteroid 
encounter in 1993 en route to its destination, the giant planet 
Jupiter and its system of moons.

   The Galileo Project is managed by NASA's Jet Propulsion 
Laboratory, Pasadena, Calif., for NASA's Office of Space Science 
and Applications.

                             -end-

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