SCIENTIFIC AND TECHNICAL AEROSPACE REPORTS

A Biweekly Publication of the National Aeronautics and Space Administration
VOLUME 44, ISSUE 6 - March 24, 2006

88 SPACE SCIENCES (GENERAL)
Includes general research topics related to the natural space sciences.

For specific topics in space sciences see categories 89 through 93.

20060008033 Florida Univ., Gainesville, FL, USA

Reflections on Jim Starnes' Technical Contributions

Haftka, Raphael T.; Collected Papers in Structural Mechanics Honoring Dr. James H. Starnes, Jr.; February 2006, pp. 1-10; In English; See also 20060008032; Original contains color illustrations; No Copyright; Avail.: CASI: A02, Hardcopy

For my generation of aerospace researchers NASA has played a crucial role in translating industry needs to research problems, orchestrating research progress in government laboratories, universities and industry, and helping transition that research to applications. Jim Starnes may have played this role better than any other NASA researcher, greatly advancing in the process our understanding of how composite materials should be best utilized for aerospace applications. This paper provides a view from a close university research collaborator on how he accomplished this remarkable feat. In particular it focuses on his vision that reducing the uncertainty in predicting failure of composite structures is key to more efficient utilization of such structures. Author

Aerospace Engineering; Composite Materials; Composite Structures; Industries

20060008116 Academia Sinica, Wuhan, China

Studies on Effects of Spaceflight and Irradiation on Photosynthetic System of Microalgae

Wang, Gao-hong; Chen, Lan-zhou; Hu, Chun-xiang; Li, Gen-bao; Chen, Kun; Li, dun-hai; Liu, Yong-ding; Space Medicine and Medical Engineering, Volume 18, No. 6; December 2005, pp. 437-441; In Chinese; See also 20060008103; Copyright; Avail.: Other Sources

Objective: To study the effect of spaceflight and radiation on the photosynthetic system of microalgae. Method: Nostoc sphaeroides Kutz was brought on board retrievable satellite or irradiated with 5,000 Gy gamma ray from Co-60 and cultured in dark as the control. Survival rate, photosynthetic activity, ration of photosynthetic pigment and ultrastructure of algal were observed after recover from the space or irradiation. Result: After recovery from spaceflight or irradiation, the survival rate and photosynthetic activity, analysis of photo-harvesting pigments and abnormality of thylakoids of photosynthetic system were found in the algae significantly, simultaneously a thick sheath was induced in the cells with spaceflight treatment. Conclusion: Spaceflight and irradiation can injure photosynthetic system of the algae, but it can adapt to these stresses through changes in ultrastructure. Author

Microorganisms; Algae; Cobalt 60; Gamma Rays; Irradiation; Space Flight

20060008588 Spectral Sciences, Inc., Burlington, MA, USA

A New Method for Atmospheric Correction and Aerosol Optical Property Retrieval for VIS-SWIR Mult- and Ulti- and Hyperspectral Imaging Sensors: Quick Atmospheric Correction

Bernstein, Lawrence S.; Adler-Golden, Steven M.; Sundberg, Robert L.; Levine, Robert Y.; Perkins, Timothy C.; Berk, Alexander; Ratkowski, anthony J.; Hoke, Michael L.; Proceedings of the 13th JPL Airborne Earth Science Workshop; December 2004, pp. 9-20; In English; See also 20060008582; Original contains color and black and white illustrations Contract(s)/Grant(s): F19628-02-C-0054; F19628-02-C-0078; Copyright;Avail.: CASI: A03, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document

A new semi-empirical algorithm, QUAC, for atmospheric correction and aerosol optical properties retrieval for VIS-SWIR HSI and MSI sensors has been developed. Initial applications of QUAC to atmospheric correction of HSI AVIRIS and MSI LANDSAT data sets show surprisingly good performance, nearly comparable to that of a first-principles physics-based code. The utility of QUAC for retrieving wavelength-dependent aerosol extinction, and by extension aerosol type, was demonstrated for several AVIRIS data sets. An initial validation of the aerosol optical properties retrieval method was accomplished through the use of a HSI scene simulation approach. Continued development and validation of QUAC is recommended using a wider variety of HSI and MSI data sets, including simulated data, and through field measurements involving full characterization of the aerosol column concurrent with airborne and/or satellite-based HSI and MSI observations. Computational speed-ups, automation, and eventually the development of an on-board data processing capability should also be explored. Author

Atmospheric Correction; Aerosols; Optical Properties; Airborne Equipment; Infrared Spectrometers; Onboard Data Processing; Landsat Satellites

20060008905 General Accounting Office, Washington, DC, USA

SPACE ACQUISITIONS: DOD Needs a Department wide Strategy for Pursuing Low-Cost, Responsive Tactical Space Capabilities

March 2006; 29 pp.; In English; Original contains black and white illustrations Report No.(s): GAO-06-449; No Copyright; Avail.: CASI: A03, Hardcopy

Through effective management of requirements and technologies and strong leadership, DOD was able to deliver the first TacSat satellite in 12 months and for less than $10 million. The Office of Force Transformation, TacSat 1's sponsor, set requirements early in the satellite's development process and kept them stable. DOD modified existing technologies for use in space, significantly reducing the likelihood of encountering unforeseen problems that could result in costly design changes. The satellite was also built within DOD's science and technology environment, which enabled service laboratory scientists to address problems quickly, inexpensively, and innovatively. The vision and support provided by leadership were also key to achieving the successful delivery of TacSat 1. DOD has also made progress in developing three additional TacSats and is working toward developing a low-cost launch vehicle available on demand.

Despite this achievement, DOD faces several challenges in providing tactical capabilities to the warfighter sooner. First, DOD has yet to develop a low-cost, small launch vehicle available to quickly put tactical satellites, including TacSat 1, into orbit. Second, limited collaboration between the science and technology and the acquisition communities as well as the acquisition community s tendency to expand requirements after program start could impede efforts to quickly procure tactical capabilities. Securing funding for future TacSat experiments may also prove difficult because they are not part of an acquisition program. Finally, DOD lacks a departmentwide strategy for implementing these efforts, and because key advocates of the experiments have left DOD, it is unclear how well they will be supported in the future.

Regardless of these challenges, DOD s experiences with the TacSat experiments thus far could inform its major space system acquisitions. DOD's approach to developing the TacSats matching requirements to available resources, using proven technologies, and separating technology development from product development reflects best commercial practices that lead to quicker delivery with less risk. According to some DOD officials, the TacSats and small, low-cost launch vehicles once they are developed could also provide an avenue for large space system acquisitions to prove out technologies in the space environment, something DOD has avoided because of the high cost of launching such experiments. These officials also believe that giving space professionals the opportunity to manage small-scale projects like TacSats may better prepare them for managing larger, more complex space system acquisitions.

Finally, these officials noted that building small-scale satellite systems and launch vehicles could create opportunities for small, innovative companies to compete for DOD contracts and thereby broaden the space industrial base. Derived from text

Aerospace Systems; Launch Vehicles; Low Cost; Satellite Design; Space Bases

Source: NASA