Donald L. Savage
Headquarters, Washington, D.C.                                                
December 15, 1993
(Phone:  202/358-1547)

Luther Young
Johns Hopkins University Applied Physics Laboratory, Laurel, Md.
(Phone:  410/792-6268)


RELEASE:  93-220

NASA BEGINS DEVELOPMENT OF FIRST ASTEROID-ORBITING MISSION

     NASA has begun full-scale development of the first spacecraft 
to rendezvous with and orbit an asteroid.  Called Near Earth 
Asteroid Rendezvous (NEAR), the mission received funding in the FY 
1994 budget and will be the first in NASA's new Discovery program 
of small-scale, cost-effective space exploration missions to be 
launched.

     NEAR is scheduled for launch in February 1996 aboard a Delta 
2 rocket with estimated arrival at the asteroid Eros in late 
December 1998.  NEAR will orbit Eros for a year at altitudes as 
low as 15 miles (24 km).  Eros will be the smallest solar system 
body ever orbited by a spacecraft.  The mission offers scientists 
their first long-term, close-up look at an asteroid.

     The Johns Hopkins University Applied Physics Laboratory 
(APL), Laurel, Md., will build and operate NEAR, becoming the 
first NASA planetary mission to be conducted by a non-NASA space 
center.

     The mission's scientific goal is to determine Eros' size, 
shape, mass and magnetic field and to measure for the first time 
an asteroid's detailed composition and surface structure.  
Asteroids are thought to include debris left over from the 
earliest days of planetary formation 4.5 billion years ago.  NEAR 
could answer important questions about solar system genesis and 
evolution.

     "NEAR represents an exciting, new approach to planetary 
exploration," said Dr. William Piotrowski, Acting Director of 
NASA's Solar System Exploration Division.  "This mission will 
answer many long-standing scientific questions about asteroids and 
it will do it far more cost-effectively than we could have in the 
past.  This is due to recent technological advances and 
innovations in spacecraft and instrument design, as well as a new 
philosophy in robotic exploration of the solar system embodied in 
the Discovery program."

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     Eros is one of the largest and best-observed of the 
"near-Earth" asteroids, many of whose orbits cross Earth's path.  
They are closely related to the more abundant "Main Belt" 
asteroids which orbit farther from the sun in the asteroid belt, a 
vast, doughnut-shaped ring between Mars and Jupiter.  During its 
journey, NEAR will fly by a small Main Belt asteroid named Illya 
in August 1996.  It also will swing by Earth for a gravity boost 
in January 1998.  

     NEAR's instruments include an x-ray/gamma ray spectrometer, a 
magnetometer, a near infrared imaging spectrograph and a 
multi-color camera fitted with a charge-coupled device CCD imaging 
detector capable of photographing details on Eros' surface as 
small as 3 feet (1 meter) in diameter.  A laser altimeter is 
aboard to assist in spacecraft navigation.  A radio science 
experiment will use the NEAR tracking system to determine the 
asteroid's gravity field.

     The NEAR spacecraft design features technologically 
innovative, state-of-the-art subsystems and instruments.  NEAR's 
experiment package is designed to emphasize simplicity, 
reliability and low cost.  Several of the instruments are derived 
from designs developed for Department of Defense spacecraft, an 
example of dual-use technology transferred to the civilian sector.

     "APL has a long history of total systems capability to do 
quick turnaround missions with low-cost, reliable 'lightsat' 
spacecraft," says Dr. Stamatios M. Krimigis, head of APL's Space 
Department.  "The execution phase of the NEAR mission is 29 
months, shorter than any in the planetary program over the past 2 
decades."

     APL will conduct mission and science operations from its 
campus outside Laurel, Md.  The NEAR mission will be managed by 
NASA Headquarters in Washington, D.C.  The NEAR Program Manager at 
NASA Headquarters is Mary E. Kicza and the Program Scientist is 
Dr. Jurgen H. Rahe.  At APL, the NEAR Project Manager is Thomas B. 
Coughlin and Robert W. Farquhar is Mission Manager.  Andrew F. 
Cheng is Project Scientist and Andrew Santo is Spacecraft Systems 
Engineer.

     Discovery missions are designed to proceed from development 
to flight in less than 3 years, combining well-defined objectives, 
proven instruments and flight systems, with total spacecraft and 
instrument development costs limited to no more than $150 million 
(in FY 1992 dollars) and acceptance of a greater level of risk.  
NEAR funding of $66.2 million was approved for this fiscal year.

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EDITOR'S NOTE:  A color print artist's conception of the NEAR 
spacecraft and a 30-second animation videotape of the NEAR 
spacecraft orbiting an asteroid are available to media 
representatives by calling the NASA Headquarters Broadcast and 
Imaging Branch at 202/358-1900.