April 26, 2013, 12:00 pm - 1:00 pm

April 26, 12:00 pm - 1:00 pm

What's the big deal about Comet ISON?

Matthew Knight, Lowell Observatory

Comet ISON (C/2012 S1) is a recently discovered sungrazing comet that will reach perihelion in November 2013 less than 2 solar radii from the Sun’s photosphere. While it is still more than 4 AU from the Sun and is currently relatively faint, it is predicted to become very bright near perihelion and has therefore gained considerable notoriety. A worldwide observing campaign to characterize ISON is underway and will include observations from the ground, space-based telescopes, solar observatories, and a number of NASA assets throughout the inner solar system. I will review past observations of sungrazing comets with SOHO, STEREO, and SDO as a means for understanding how Comet ISON is likely to behave near perihelion and how it might be useful as a “solar probe.” I will also discuss the current state of knowledge of Comet ISON, using ground- and space-based observations to predict how likely it is to survive perihelion. Finally, I will discuss the epochs at which ISON will be observable by different methods (including naked eye) and what new science may be revealed.