NASA/Goddard Space Flight Center, Code 219, Greenbelt, MD 20771

66 -- SPECTRAL RADIOMETERS (SUNPHOTOMETERS) DUE 070999 POC Cosimo Lucchese, Contract Specialist, Phone (301)614-5584, Fax (301)614-5619, Email clucches@pop200.gsfc.nasa.gov -- Rex T. Elliott, Contracting Officer, Phone (301)286-6204, Fax (301)286-0247, Email Rex.T.Elliott.1@gsfc.nasa.gov WEB: Click here for the latest information about this notice, http://nais.nasa.gov/EPS/GSFC/date.html#SUN-PHOT. E-MAIL: Cosimo Lucchese, clucches@pop200.gsfc.nasa.gov. NASA/GSFC is hereby soliciting information for potential sources for Automatic Sun and Sky Scanning Spectral Radiometers in support of the AERONET program. Sun and sky scanning spectral radiometers are used under this program to monitor aerosol optical properties and precipitable water in near real time for validation of satellite-derived retrievals of aerosol properties and to provide a uniform database for long-term characterization of aerosol optical properties within NASA's global climate change program. This instrument must be capable of measuring both sun and sky using a combination of spectral filters and a fully autonomous azimuth/zenith-viewing microprocessor-controlled robot. It must be capable of automatically changing gains from the sky-radiance-measurement mode to the sun-measurement mode without saturating signal response. A two-detector/two-collimator system is required in order to assess the quality of data from each detector system. The instrument must possess eight filters with the following centerband/nanometer bandwiths: 340/2, 380/4, 440/10, 675/10, 870/10, 940/10,940/50, and 1020/10. Optical characteristics include a collimator/detector for sun measurements with 1 degree FOV, no optics sky, collimator 1 degree FOV, lens required 10-5 stray light rejection relative to the sun at 2 degrees from sun.. The instrument shall have four quad silicon cells for sun tracking, w silicon sensors for sun and sky radiance in the 0.25-1.1 micron range. The instrument must be battery-powered and rechargeable from solar cells. It must be sealed from rain, humidity, dust and smoke and operate successfully within a temperature range of -40 to 60 degrees Celsius for a year with minimum maintenance. The instrument must have a demonstrated capability to communicate with the Vitel VX-1004 data collection platforms to transmit data via the international Data Collection System. No solicitation exists; therefore, do not request a copy of the solicitation. If a solicitation is released it will be synopsized in the CBD and on the NASA Acquisition Internet Service. It is the potential offerors responsibility to monitor these sites for the release of any solicitation or synopsis. Vendors having the capabilities necessary to meet or exceed the stated requirements are invited to submit appropriate documentation, literature, brochures, and references. Technical and procurement-related questions should be directed to Cosimo Lucchese at the contact points below. The Government intends to acquire a commercial item using FAR Part 12. The commercial instrument most commonly used by NASA for this application is the Cimel Model CE-318 Photometre Automatique. Please see Internet Note "A". This synopsis is for information and planning purposes and is not to be construed as a commitment by the Government nor will the Government pay for information solicited. Respondents will not be notified of the results of the evaluation. Respondents deemed fully qualified will be considered in any resultant solicitation for the requirement. Posted 06/09/99 (D-SN341157). (0160)

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