Debra J. Rahn
Headquarters, Washington, D.C.                                              
August 8, 1991
(Phone:  202/453-8455)


RELEASE:  91-126

U.S. AND ARGENTINA SIGN SPACE COOPERATION AGREEMENTS

   In Buenos Aires, Argentina, Vice President Dan Quayle and 
Argentine President Carlos Menem today signed an agreement for 
cooperation in the civil uses of space, with special emphasis 
on Earth and space sciences.  This agreement establishes a 
framework for future cooperative space projects between NASA 
and the newly formed Argentine National Commission on Space 
Activities (CONAE). 

   During the same ceremony, U.S. Ambassador to Argentina 
Terence A. Todman and Raul F. Matera, the Argentine Secretary 
of State for Science and Technology, signed an agreement to 
cooperate in a solar physics and astrophysics satellite 
mission, Satelite de Aplicaciones Cientificas-B (SAC-B).  SAC-B 
will be the first joint spacecraft mission undertaken by NASA 
and a Latin American country. 

   The SAC-B mission will advance the study of solar physics 
and astrophysics through the examination of high energy, hard 
X-ray emissions from solar flares and cosmic gamma-ray burst 
sources and the examination of the spectrum and intensity of 
the diffuse, low energy, soft X-ray cosmic background 
radiation. 

   By studying x-rays from solar flares, U.S. and Argentine 
scientists expect to learn about the explosive acceleration of 
particles that occurs during solar flares.  The diffuse x-ray 
cosmic background comes from the million-degree gas that can be 
found in the space between stars, and SAC-B data will be used 
to investigate the nature of the gas.

   By obtaining the precise time of arrival of cosmic gamma-ray 
bursts at SAC-B and comparing it to times measured on 
interplanetary spacecraft, scientists can precisely locate 
sources of gamma-ray bursts.  The nature of the sources of 
cosmic gamma-ray bursts remains a mystery until the source is 
identified with an object seen at other wavelengths.

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   Under the SAC-B agreement, CONAE will build the spacecraft, 
and the Institute of Astronomy and Space Physics will provide a 
solar X-ray instrument.  NASA will provide an X-ray cosmic 
background instrument built by Penn State University and X-ray 
spectrometers provided by NASA's Goddard Space Flight Center, 
Greenbelt, Md.  SAC-B will be scheduled for launch on a U.S. 
expendable launch vehicle. 

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