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Smith, Bradford A.

Publications and source records attributed to Smith, Bradford A..

3 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1987

A dynamical constraint on particulate sizes for Saturn's B ring spokes

The exponential charge decay time for particulates constituting the spokes in Saturn's B ring is presently proposed as a dynamical time scale for their evolution. Mean particulate radius is determined to be 0.01 + or - 0.03 microns, on the basis of a consideration of solar UV photoemission as the charge decay mechanism which leads to the determination of a dynamical constraint that can be placed on the particulate sizes.

Eplee, Robert E., Jr.↗
NASA NTRS1987

Coronagraph for astronomical imaging and spectrophotometry

A coronagraph designed to minimize scattered light in astronomical observations caused by the structure of the primary mirror, secondary mirror, and secondary support structure of a Cassegrainian telescope is described. Direct (1:1) and reducing (2.7:1) imaging of astronomical fields are possible. High-quality images are produced. The coronagraph can be used with either a two-dimensional charge-coupled device or photographic film camera. The addition of transmission dispersing optics converts the coronagraph into a low-resolution spectrograph. The instrument is modular and portable for transport to different observatories.

Vilas, Faith↗