Engineering topics

Donahue, M. E.

Publications and source records attributed to Donahue, M. E..

3 records

NASA NTRS1986

X-ray studies of galactic and intergalactic gas in the Pegasus I cluster

Einstein Observatory IPC observations of Pegasus I show hot gas in a low density intergalactic medium as well as in a galactic medium within each of the dominant elliptical galaxies, NGC 7619 and NGC 7626. The short central cooling times inferred, of 100 million years or less, suggest that the galaxies contain cooling flows of about 1 solar mass/yr. The intergalactic gas, which is about 5 times less dense than in the least dense of the known Abell clusters, is incapable of stripping the hot gas from the elliptical galaxies or the neutral gas from the spirals. The gas around NGC 7619 appears to be influencing one of the radio lobes of NGC 7626.

Canizares, C. R.↗

NASA NTRS1985

Observations of four nearby galaxies with the Einstein Observatory

Four nearby galaxies, NGC 205, NGC 6822, the dwarf elliptical galaxy in Uras Major, and Maffei 1, were studied with the imaging instruments on the Einstein Observatory, and the results are reported. Fifteen X-ray sources were discovered, eight of which may not be associated with the target galaxies. No X-ray source was found in NGC 205, and one was found in NGC 6822, probably the optical supernova remnant Hodge 12. There are at most three sources in the Ursa Minor galaxy. There is probably an extended source associated with the Maffei 1 galaxy.

Markert, T. H.↗

NASA NTRS1985

Payload transportation at KSC

Cargo ground processing at John F. Kennedy Space Center (KSC) involves either a horizointal or vertical mode of assembly and processing of the STS payloads. Consequently, cargos are commonly referred to as horizontal or vertical payloads. The process flow for each mode requires different facilities and transportation requirements. Occasionally, a mixed mission cargo containing both horizontal and vertical payload elements will require a combination of horizontal and vertical transportation between facilities. Some of the engineering challenges and innovative solutions to satisy the unique on-site payload transportation requirements at KSC. In particular, some of the more demanding design requirements of the multiuse mission support equipment are presented, and the resulting engineering designs and unique solutions are outlined.

Donahue, M. E.↗