Title: The Algol triple system spatially resolved at optical wavelengths Authors: R. T. Zavala (1), C. A. Hummel (2), D. A. Boboltz (3), R. Ojha (3), D. B. Shaffer (4), C. Tycner (5), M. T. Richards (6), D. J. Hutter (1) ((1) U.S. Naval Observatory, Flagstaff Station, (2) ESO, (3) U.S. Naval Observatory, Washington, D.C., (4) Lowell Observatory, (5) Central Michigan University, (6) The Pennsylvania State University)
Interacting binaries typically have separations in the milli-arcsecond regime and hence it has been challenging to resolve them at any wavelength. However, recent advances in optical interferometry have improved our ability to discern the components in these systems and have now enabled the direct determination of physical parameters. We used the Navy Prototype Optical Interferometer to produce for the first time images resolving all three components in the well-known Algol triple system. Specifically, we have separated the tertiary component from the binary and simultaneously resolved the eclipsing binary pair, which represents the nearest and brightest eclipsing binary in the sky. We present revised orbital elements for the triple system, and we have rectified the 180-degree ambiguity in the position angle of Algol C. Our directly determined magnitude differences and masses for this triple star system are consistent with earlier light curve modelling results.
Radio Telescopes Help Astronomers Find Double-Star System
Astronomers have found a giant magnetic loop stretched outward from one of the stars making up the famous double-star system Algol. The scientists used an international collection of radio telescopes to discover the feature, which may help explain details of previous observations of the stellar system. Read more
UI astronomers capture first-of-kind image at distant star
Two University of Iowa researchers have made the first direct radio image of a stellar coronal loop at a star, other than the sun, thereby providing scientists with information that may lead to a better understanding of how such phenomena as space weather affect the Earth. Robert Mutel, professor in the University of Iowa College of Liberal Arts and Sciences Department of Physics and Astronomy, and his graduate student William Peterson of Marshalltown, Iowa, spearheaded the research, which included astronomers from New Mexico and Switzerland. They published their findings in the Jan. 14 issue of the Journal Nature. Read more
Giant Magnetic Loop Sweeps Through Space Between Stellar Pair
Astronomers have found a giant magnetic loop stretched outward from one of the stars making up the famous double-star system Algol. The scientists used an international collection of radio telescopes to discover the feature, which may help explain details of previous observations of the stellar system.
"This is the first time we've seen a feature like this in the magnetic field of any star other than the Sun" - William Peterson, of the University of Iowa.
The pair, 93 light-years from Earth, includes a star about 3 times more massive than the Sun and a less-massive companion, orbiting it at a distance of 5.8 million miles, only about six percent of the distance between Earth and the Sun. The newly-discovered magnetic loop emerges from the poles of the less-massive star and stretches outward in the direction of the primary star. As the secondary star orbits its companion, one side -- the side with the magnetic loop -- constantly faces the more-massive star, just as the same side of our Moon always faces the Earth.