David E. Steitz
Headquarters, Washington, DC                   October 27, 1998
(Phone:  202/358-1730)

RELEASE:  98-198

TRIANA MISSION SELECTED 

     After a rigorous peer-review evaluation of nine competing 
proposals, NASA has selected  a proposal from the Scripps 
Institution of Oceanography in La Jolla, CA, to implement the 
Triana mission with NASA's Goddard Space Flight Center, Greenbelt, 
MD.

     Named for the sailor on Columbus' voyage who first saw the 
New World, Triana is a satellite mission to L1 (the Lagrange 
libration, or neutral gravity point between the Earth and the 
Sun).  From L1, Triana will have a continuous, full disk, sunlit 
view of the Earth.  The mission will provide this view of the 
Earth for distribution over the Internet at the beginning of the 
new millennium. 

     Dr. Francisco P.J. Valero of the Scripps Institution of 
Oceanography, a part of the University of California at San Diego, 
has been selected the Principal Investigator to lead development 
of the Triana mission.  Dr. Valero's mission concept includes two 
scientific instruments:  the Earth Polychromatic Imaging Camera 
(EPIC), to be built by Lockheed-Martin Advanced Technology Center 
of Palo Alto, CA, and an advanced radiometer, from a source to be 
selected later this fall. Triana also will include a small, next-
generation space weather monitoring instrument to contribute to 
our understanding of how solar events affect Earth-orbiting 
spacecraft, such as communications satellites.

     "An advanced radiometer at L1 will provide, by looking at the 
whole sunlit side of the Earth at once, the first direct 
measurements of the radiant power reflected by the planet, and 
thereby contribute to our knowledge of how much of the Sun's 
energy is absorbed in the Earth's atmosphere," said Dr. Valero.  
"The EPIC instrument will observe the Earth's vegetation canopy 
structure and evolution by taking advantage of the retro-
reflectance, or 'hot spot,' view that will be available by being 
in-line between the Earth and the Sun. The EPIC also will observe 
clouds and aerosols."

     "The L1 vantage point, with its full-disk view of the Earth, 
offers unique scientific advantages," said Dr. Ghassem Asrar, 
NASA's Associate Administrator for Earth Science.  "The full-disk 
view of the Earth enables retrieval of global quantities at once, 
whereas measurements from low Earth orbit or geostationary Earth 
orbit must be 'stitched' together, requiring concerted efforts to 
'process out' differences due to viewing times and revisit 
intervals.

     "L1 will be a prime vantage point for the next generation of 
Earth remote-sensing instruments.  Triana will serve as a 
pathfinder for those future missions, providing scientific and 
operating experience in the L1 environment," said Asrar.

     The Triana mission also will invite participation from the 
educational community.  "We hope and expect to have widespread 
participation by students in every phase of this inspirational 
project. Students will benefit from 'hands-on' participation in 
Triana via the Internet and NASA's educational outreach efforts," 
Asrar said.  NASA plans to solicit proposals for educational 
applications of Triana data next year.

     Commercial participation also is possible for the Triana 
mission.  Commercial enterprises have expressed an interest in 
contributing financially to Triana development in exchange for 
commercial rights to data.  NASA will consider commercial 
partnerships for the Triana mission over the coming months.

     NASA plans to proceed expeditiously on mission development.  
Goddard will provide a Small Explorer-lite spacecraft and ground 
system for Triana, as well as program integration and management 
support.  Triana is a $75 million mission to be launched by 
December 2000 from the Space Shuttle cargo bay.  Triana will be 
the latest in the Earth Probe series of missions in NASA's Earth 
Science enterprise, which seeks to understand the total Earth 
system and the effects of natural and human-induced changes on the 
global environment.

                            -end-

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