October 27, 1998
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.