Thursday, September 20, 2018 at 4:00pm
Space Sciences Building, 105 122 Sciences Drive
William E. & Elva F. Gordon Distinguished Lectureship
Speaker: Dr. Gregg Hallinan, Caltech
Imaging All the Sky All the Time in Search of Radio Exoplanets
All the magnetized planets in our solar system, including Earth, produce bright emission at low radio frequencies, predominantly originating in high magnetic latitudes and powered by magnetospheric currents. It has long been speculated that similar radio emission may be detectable from exoplanets orbiting nearby stars, potentially providing the first direct confirmation of the presence, strength and topology of exoplanet magnetospheres, and informing on their role in shielding the atmospheres of potentially habitable exoplanets. Despite 4 decades of searching, no exoplanet radio emission has been detected. Surprisingly, however, brown dwarfs have been found to produce both radio and optical emissions that are strikingly similar to the auroral emissions from solar system planets, albeit 100,000 times more luminous. Dr. Hallinan will discuss the radio emission from exoplanets and brown dwarfs with particular focus on the OVRO-LWA, a low frequency radio astronomy array located in the Owens Valley, California, that images the entire sky every 10 seconds to simultaneously monitor 4000 nearby stellar systems in the search for radio emission from exoplanets.
William E. Gordon, then professor of electrical engineering at Cornell, proposed the construction of the Arecibo telescope in 1958 to study the Earth's ionosphere via the incoherent scatter of powerful radio waves from the individual electrons in the ionospheric plasma. Gordon raised the funding for the telescope and organized its construction. Completed in 1963, the 305m (1000ft) diameter telescope and its powerful radar systems have been continuously upgraded over the intervening years and have been used to made major advances in the areas of ionospheric physics, radio astronomy and planetary science.
The Gordon Lectures are made possible by an endowment by Tom and Betty Talpey. Tom and Betty Talpey were one of the families that moved with the Gordon's to Arecibo in the summer of 1960 to supervise the telescope's construction and build the observing instrumentation.