Aberrations of radio signals traversing the auroral ionosphere interim report no. 1, 1 aug. 1964 - 31 jan. 1965
Radio star signal measurement beneath auroral ionosphere for satellite tracking
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Radio star signal measurement beneath auroral ionosphere for satellite tracking
Radio star signal visibility fading observed in auroral zone by phase-switching interferometer
Neutrino astrophysics - supermassive stars, quasars, and extragalactic radio sources
Optical observations of supermassive stars, quasars, and identification of extragalactic radio sources
Radio interferometric observations on lunar occultations of Crab Nebula
Radio astronomy studies using high sensitivity antenna arrays - lunar occultations of Crab Nebula, solar radio bursts, and long wavelength observations of radio stars
Photographic and radio observations of radio emissions of flare stars, accomplished by the radio telescopes at jordell bank and by baker-nunn cameras
X-y mounted, 85 foot diameter, parabolic antenna system for solar, radio star and satellite tracking
Neutron stars considered as origin of X-ray emission from Scorpius and Crab Nebula
Correlation of radio and optical emission from flare star compared with frequency-drift type solar radio burst
Four mile antenna grating array for long wavelength observations of star transits
Red shifts of quasi-stellar objects and relation to radio and optical magnitudes, concluding that red shifts have no relation to distance
Jovian decametric pulses compared with satellite and radio star scintillations in terrestrial ionosphere
Radio star Cassiopeia A scintillations and spread-F in auroral zone
NASA's SETI-Microwave Observing Project, beginning on October 12, 1992, will search the closest solar-type stars for radio signals from extraterrestrial civilizations. When completed in the year 2000, the NASA search will have surpassed the search volume of all prior searches by a factor of 10 exp 10. The world's largest radio telescopes will be employed, in conjunction with the NASA Deep Space Network communications antennas. The program will be led by NASA-Ames, with substantial contribution by JPL.
An antenna gain measurement method was developed which utilizes a signal emitted from a radio star to determine absolute antenna gain at 136 MHz and 400 MHz for antennas in the STADAN network. An error analysis of the radio star method shows that the overall standard deviation uncertainty in antenna gain is + or - 0.6 db (1 sigma).
High spatial resolution continuum radio maps produced by the Westerbork Synthesis Radio Telescope (WSRT) of The Netherlands at frequencies near the 21 cm HI line have been examined for anomalous sources of emmission coincident with the locations of nearby bright stars. From a total of 542 stellar positions investigated, no candidates for radio stars or ETI signals were discovered to formal limits on the minimum detectable signal ranging from 7.7 x 10(-22) W/m2 to 6.4 x 10(-24) W/m2. This preliminary study has verified that data collected by radio astronomers at large synthesis arrays can profitably be analysed for SETI signals (in a non-interfering manner) provided only that the data are available in the form of a more or less standard two dimensional map format.
Rytov's approximation, or the method of smooth perturbations, is utilized to derive the temporal frequency spectra of the amplitude and phase fluctuations of multifrequency plane and spherical waves propagating in the interplanetary medium and solar corona. It is shown that multifrequency observations of interplanetary scintillations using either compact radio stars of spacecraft radio signals are desirable because the correlation of the multifrequency waves yields additional independent measurements of the solar wind and turbulence. Measurements of phase fluctuations are also desirable because, unlike amplitude fluctuations, they provide information on the full range of scale sizes for the electron-density fluctuations. It is also shown that a coherent dual-frequency radio system is particularly useful in making such measurements. In addition to providing a means for interpreting observations of multifrequency interplanetary scintillations, the present analysis is essential for estimating the effects of solar corona turbulence on the communications and navigation of a spacecraft whose line-of-sight path passes close to the sun.