A growth path for deep space communications

Increased Deep Space Network (DPN) receiving capability far beyond that now available for Voyager is achievable through a mix of increased antenna aperture and increased frequency of operation. In this note a sequence of options are considered: adding midsized antennas for arraying with the existing network at X-band; converting to Ka-band and adding array elements; augmenting the DSN with an orbiting Ka-band station; and augmenting the DSN with an optical receiving capability, either on the ground or in space. Costs of these options are compared as means of achieving significantly increased receiving capability. The envelope of lowest costs projects a possible path for moving from X-band to Ka-band and thence to optical frequencies, and potentially for moving from ground-based to space-based apertures. The move to Ka-band is clearly of value now, with development of optical communications technology a good investment for the future

Polarimetric measurements of simulated lunar surfaces Third interim report

Polarimetric measurements of simulated lunar surfaces for determining Apollo landing area

Financial Conditions on U.S. Cotton Farms

For the last three years, U.S. cotton producers have been heavily dependent on ad hoc emergency disaster and market loss assistance to cash flow their operations. They have not been alone. Wheat, feed grains, oilseeds and rice producers have also been faced with low commodity prices, adverse weather and the need for substantial government assistance. Price support and direct payments by CCC for fiscal years 1998-2000 averaged $17.5 billion per year (USDA Ag Outlook). Has U.S. program crop agriculture turned the corner or will additional government payments likely be needed to sustain a vulnerable sector? This paper will focus on the outlook for the Agricultural and Food Policy Center’s (AFPC’s) representative cotton farms over the period 2001-2005. The results reported herein are drawn from AFPC Working Paper 00-4 which goes into greater depth on all 82 representative farms and ranches modeled by AFPC.Agribusiness, Agricultural and Food Policy, Crop Production/Industries,

Low gravity phase separator

An apparatus is described for phase separating a gas-liquid mixture as might exist in a subcritical cryogenic helium vessel for cooling a superconducting magnet at low gravity such as in planetary orbit, permitting conservation of the liquid and extended service life of the superconducting magnet