Search Publications
The Use of Gamma-Ray Bursts as Direction and Time Markers in SETI Strategies
Corbet, Robin H. D.
When transmitting a signal over a large distance, it is more efficient to send a brief beamed signal than a continuous omnidirectional transmission, but this requires that the receiver knows where and when to look for the transmission. For SETI, the use of various natural phenomena has previously been suggested to achieve the desired synchronizati…
Detection of O VII lambda1522 in IUE Spectra of Planetary Nebula Nuclei and Other Hot Stars
Feibelman, Walter A.
We present the first detection of O VII lambda1522 emission or absorption from archival IUE spectra in 14 planetary nebula nuclei and three PG 1159-type stars. The n=5-->6 transition of O VII was determined by Kruk & Werner and observed by them in the spectrum of the very hot PG 1159-type star H1504+65 from data obtained with the Hopkins Ul…
Intereclipse Spectroscopic Snapshot of epsilon Aurigae with the Hubble Space Telescope
Lambert, David L.; Sheffer, Yaron
A single-epoch low-resolution Goddard High Resolution Spectrograph spectrum of the eclipsing binary epsilon Aurigae was obtained while the secondary was orbiting toward eclipse by the primary. The spectrum as recorded between 1175 and 1461 Å is rich with emission and absorption lines which include stellar and interstellar components. The emission-…
Ultraviolet Evidence for a Binary Nucleus of the Planetary Nebula SH 2-71
Feibelman, Walter A.
Archival IUE spectra of the planetary nebula Sh 2-71 show a variable Mg II lambda2800 emission line superposed on a variable stellar continuum. The Mg II feature is thought to be excited in the chromosphere of the cooler component of a binary nucleus, although other causes are also plausible.
Hubble Space Telescope Astrometric Observations of the Metal-poor Spectroscopic Binary HD 20039
Hershey, John L.; Osborn, Wayne
An attempt has been made to spatially resolve the metal-poor, double-lined spectroscopic binary HD 20039 with the Hubble Space Telescope Fine Guidance System. Astrometric measurements of the system to complement the spectroscopic orbit would permit the distance and the masses of the components to be determined. Observations were obtained around th…
Space Telescope Imaging Spectrograph Parallel Observations of the Planetary Nebula M94-20
Gull, Theodore R.; Plait, Philip
The planetary nebula M94-20 in the Large Magellanic Cloud was serendipitously observed with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope as part of the Hubble Space Telescope Archival Pure Parallel Program. We present spatially resolved imaging and spectral data of the nebula and compare them with ground-based data,…