Target of Opportunity: Comet ISON
NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) took off on a “target of opportunity” flight that included study of Comet ISON on Oct. 24, 2013. This was SOFIA's second opportunity to capture data on a comet, having previously studied Comet Hartley 2 in 2010. For the Comet ISON observations, the object was predicted to be very faint.