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Pellicori, S. F.

Publications and source records attributed to Pellicori, S. F..

17 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1980

Scattering defects in silver mirror coatings

Scatter centers common to protected silver have been investigated on a variety of space flight quality mirrors. The defects have been characterized as to number density, size, location within the film layer structure, and dependence on illumination angle. In addition the total integrated scatter values as a function of wavelength, humidity test soak time, and temperature have been determined for some mirrors. These submicrometer sized defects are believed to be the precursors of silver corrosion spots. A mechanism for their generation is proposed, and measures to reduce their occurrence are suggested.

Pellicori, S. F.↗
NASA NTRS1977

Orbiter Cloud Photopolarimeter for the Pioneer Venus mission

The Orbiter Cloud Photopolarimeter (OCPP) to be flown aboard the Pioneer Venus Orbiter spacecraft is described. This instrument, while in orbit about the planet Venus, will perform polarimetric and radiometric mapping of the Venus atmosphere in four spectral bands centered in the near ultraviolet, visible, and near infrared regions. Additionally, the instrument is equipped to provide moderate resolution imaging of the time varying cloud patterns in the near ultraviolet. In another mode of operation the instrument is capable of profiling the atmosphere at the limb of the planet to measure the particulate layering. Information resulting from these measurements is intended to provide an understanding of the global cloud dynamics and the atmospheric structure and composition on Venus. The basic operation and functional elements of the instrument are discussed. The optical configuration incorporating a polarization analyzing technique with improved accuracy is described. Long-term and short-term calibration techniques along with expected instrument performance characteristics are summarized.

Russell, E. E.↗
NASA NTRS1974

Study of spin-scan imaging for outer planets missions

The constraints that are imposed on the Outer Planet Missions (OPM) imager design are of critical importance. Imager system modeling analyses define important parameters and systematic means for trade-offs applied to specific Jupiter orbiter missions. Possible image sequence plans for Jupiter missions are discussed in detail. Considered is a series of orbits that allow repeated near encounters with three of the Jovian satellites. The data handling involved in the image processing is discussed, and it is shown that only minimal processing is required for the majority of images for a Jupiter orbiter mission.

Russell, E. E.↗
NASA NTRS1974

Study of spin-scan imaging for outer planets missions: Executive summary

The development and characteristics of spin-scan imagers for interplanetary exploration are discussed. The spin-scan imaging photopolarimeter instruments of Pioneer 10 and 11 are described. In addition to the imaging function, the instruments are also used in a faint-light mode to take sky maps in both radiance and polarization. The performance of a visible-infrared spin-scan radiometer (VISSR), which operates in both visible and infrared wavelengths, is reported.

Russell, E. E.↗
NASA NTRS1973

Pioneer imaging photopolarimeter optical system.

The imaging photopolarimeter aboard the Pioneer 10 spacecraft en route to the vicinity of Jupiter is described. This instrument is capable of moderate resolution spin-scan imaging and high precision polarimetric and photometric mapping of Jupiter in red and blue light. The field of view can be selectively changed from 0.50 mrad square to 40 mrad square to accommodate resolution and radiance combinations ranging from the zodiacal background to that of Jupiter. Optical materials were chosen to survive, with minimum degradation, the rigors of a nearly 2-year journey to Jupiter including transit through the Jovian trapped radiation belts. The optics are described in detail, and the operational system is outlined. The procedures for preflight and in-flight calibration are described, and some performance characteristics and preliminary flight results are presented.

Pellicori, S. F.↗
NASA NTRS1972

Outer planet Grand Tour missions photometry/polarimetry experiment critical components study

Work performed during this effort was limited to two primary areas of technical concern: optical design optimization, and sensor selection. An optical system concept was established, and various system components were evaluated through experimental test sequences. Photodetectors were investigated for the applicability in meeting OPGT requirements as constrained by the photometry/polarimetry team directives. The most promising (gallium arsenide PMT) was further experimentally tested to ascertain its behavior with respect to anticipated environmental conditions. Results of testing and summary of the preceding tradeoff study effort are presented.

Pellicori, S. F.↗
NASA NTRS1972

Optical bonding agents for severe environments

Test results and applications of elastors (General Electric RTV 665, Dow Corning (DC) XR-63-488, DC 93-500, DC 182, and DC 184) considered for use as optical bonding agents in aerospace environments are presented.

Pellicori, S. F.↗