Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “radio telescope”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
NASA NTRS1988

Very long baseline interferometry observations using the tracking and data relay satellite as an orbiting radio telescope

An antenna in geostationary orbit was used for VLBI observations at 2.3 GHz, in combination with ground antennas in Australia and Japan. 23 of the 25 observed sources were detected on orbiter-ground baselines, with baseline lengths as large as 2.15 earth diameters. Brightness temperatures between 10 to the 12th K and 4 x 10 to the 12th K were measured for 10 sources.

Linfield, R. P.↗
NASA NTRS1990

Millimetre observations of comets P/Brorsen-Metcalf (1989o) and Austin (1989c1) with the IRAM 30-m radio telescope

Millimeter observations with the IRAM 30 m telescope were conducted in comet P/Brorsen-Metcalf (1989o) on September 1989 and Austin (1989c1) on April and May 1990. The HCN J(1-0) and J(3-2) lines were detected in both comets. The HCN production rate relative to water in P/Brorsen-Metcalf is comparable to that previously measured in comet P/Halley, while that inferred in comet Austin might be smaller by a factor of two. The H2CO(3 sub 12 - 2 sub 11) transition, marginally observed in comet P/Brorsen-Metcalf, was firmly detected in May 1990 in comet Austin. Observations performed at offset positions suggest that the source of H2CO might be distributed. The H2CO abundance is on the order of 0.5 percent that of water for both comets, assuming a scalelength of 10(exp 4) km at 1 AU from the Sun for the distributed source. During the May observing period of comet Austin, two new species were detected for the first time in a comet: hydrogen sulfide (H2S) through its 1(sub 10) - 1(sub 01) ortho line at 169 GHz, and methanol (CH3OH) through J(3-2) delta K = 0 transitions at 145 GHz. Preliminary estimates of their abundances are 1.5 x 10(exp -3) for H2S and 8 x 10(exp -3) for CH3OH.

Colom, P.↗