The Solar Corona from Eclipse and Spacecraft Observations
October 3, 4:00 pm, 105 Space Sciences Building
Since my first month as a freshman at Harvard, I've been observing solar eclipses, and I've now seen 57, with the 58th to come in Gabon in November. (The end of the partial phases will be visible low in the eastern horizon from Cornell on November 3's sunrise.) My students, colleagues, and I have been studying, at the total solar eclipses, especially how the solar corona is heated to millions of kelvins even though it is above the solar photosphere, which is only about 6000 kelvins. In recent years, we have been studying especially motions of coronal plumes, coronal mass ejections, and streamers as measured during totality with simultaneous observations from a variety of spacecraft, including the ESA/NASA Solar and Heliospheric Observatory, NASA's Solar Dynamics Observatory, the Sun Watcher on ESA's PROBA2, and NASA's STEREO pair of spacecraft. Our most recent efforts with such overlapping observations were at the total eclipses in Siberia in 2008, China in 2009, Easter Island in 2011, and Australia in 2012. Further, science at annular eclipses include our observations of the 2012 annular eclipse with the Jansky Very Large Array to try to improve on the JVLA's native resolution, which is already high. Finally, I will discuss plans and projections for the 21 August 2017 total solar eclipse whose path of totality will cross the Continental United States from Oregon to South Carolina, with a clickable/zoomable map accessible through my website for the International Astronomical Union's Working Group on Eclipses at http://www.eclipses.info or directly to http://xjubier.free.fr/en/site_pages/solar_eclipses/xSE_GoogleMapFull_Test.php?Ecl=+20170821&Acc=1&Umb=0&Lmt=1&Mag=1&Max=1. At its maximum in Ithaca, 75% of the solar diameter will be covered. My current work on eclipses is supported by grants from the Solar Research Program of the Atmospheric and Geospace Sciences Division of NSF for studies of the two solar eclipses of 2012 and from the Committee for Research and Exploration of the National Geographic Society for the 2013 eclipse expedition.