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Shaffer, R. D.

Publications and source records attributed to Shaffer, R. D..

10 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1983

Radio Astronomy

Deep Space Network (DSN) 26- and 64-meter antenna stations were utilized in support of Radio Astronomy Experiment Selection Panel experiments. Within a time span of 10 days, in May 1983 (267.75 hours total), nine RAES experiments were supported. Most of these experiments involved multifacility interferometry using Mark 3 data recording terminals and as many as six non-DSN observatories. Investigations of black holes, quasars, galaxies, and radio sources are discussed.

Wolken, P. R.↗
NASA NTRS1983

Planetary Radar

The application of modern planetary radar techniques to a comet passing in close proximity to Earth is discussed. These techniques have the potential to determine the nature of cometary origins, structure, and internal dynamics. Moreover, the understanding gained could very likely negate or corroborate one of the prevailing hypotheses regarding the origin of the solar system: that comets are the remainder of the primordial out of which the planets coalesced approximately 4.5 billion years ago. In 1983, two unique opportunities were presented to observe a comet very near to Earth. The last such encounter was several centuries ago.

Bogan, J. R.↗
NASA NTRS1982

Radio astronomy

Use of the Tidbinbilla Interferometer to refine the source positions in the Parkes 2.7 GHz survey of the southern sky is described. A result of the first phase of this work was the identification of a quasi-stellar object which appears to be the most remote object yet observed. This object has a red shift of 3.78 (PKS 2000-330, and a velocity of recession equal to 91% of that light. Based on Hubble's law, PKS 2000-330 appears to be 12 billion light years away.

Shaffer, R. D.↗
NASA NTRS1981

Radio astronomy

A K-band reflected-wave ruby maser was used on the 64-meter (DSS-43) antenna at the Tidbinbilla Tracking Station, near Canberra, Australia. Spectral line observations were carried out near 22 GHz for water vapor sources and near 24 GHz for ammonia sources. The water vapor observations were made in the direction of known southern OH and H2O maser sources. All of the previously detected water line sources examined were detected. In addition, two new water vapor maser sources were discovered, G301.1+1.1and G308.9+0.1. The spectrum of G301.0+1.1 is presented six ammonia sources were found: G291.3-0.7, G305.4+0.2, G322.2+0.6, G327.3-0.5, G333.6-0.2, and G268.4-0.8. Spectra of two of these sources, G291.3-0.7 (RCW 57) and G305.4+0.2, are presented. Both show clearly the presence of the quadrupole splitting satellite lines that will allow the determination of NH3 optical depths in these clouds.

Shaffer, R. D.↗
NASA NTRS1981

A dedicated 26-m SETI sky survey instrument facility: A feasibility study

The feasibility of converting a deactivated GSTDN 26 m facility into a dedicated SETI Instrument Facility is examined. Additional benefits that would accrue from the proposed utilization of these facilities are the capability for remote and control the Deep Space Communications Complex (DSCC) Signal Processing Center, combined with a reduction in ground-induced radio frequency interference due to the physical distance to the other DSCC front end areas and the Signal Processing Center.

Berman, A. L.↗
NASA NTRS1981

Planetary radar

The radar astronomy activities supported by the Deep Space Network during the third quarter of FY81 are reported. The planet Mercury was the principal object of interest.

Shaffer, R. D.↗
NASA NTRS1981

Radio astronomy

The activities of the Deep Space Network in support of radio astronomy operations during the first quarter of 1981 are reported. Results of the use of a low noise maser are presented, as well as updates in DSN support of experiments sanctioned by the Radio Astronomy Experiment Selection Panel.

Shaffer, R. D.↗
NASA NTRS1981

Planetary radar

The radar astronomy activities supported by the Deep Space Network during the first quarter of 1981 are reported. The bodies observed include the asteroids Apollo and Toro, comet Bradfield, and the rings of Saturn.

Shaffer, R. D.↗
NASA NTRS1981

Radio Astronomy

The activities of the DSN in support of Radio and Radar Astronomy Operations during September through December 1980 are described. Emphasis is on a report of an experiment selected for use of the DSN by the radio Astronomy Experiment Selection Panel: that of VLBI observations of the energetic galactic object SS-433.

Shaffer, R. D.↗