One year ago, the astronomy community was gripped with anticipation as sungrazing comet C/2012 S1 (ISON) was just weeks away from an unprecedented close encounter with the Sun on November 28, 2013. Comet ISON held the potential of being a spectacular nighttime object - but its fate hinged on surviving a passage that would take it to within just 1.1-million kilometers of the solar surface. To the great disappointment of a global audience, the comet did not survive, fading rapidly in the hours surrounding perihelion and disappearing from sight in the following days. For the first half of the talk I will recap some of the background regarding ISON, and highlight the main points of interest during its well-observed final year of approach to the Sun. I will focus in particular on the final few days and hours of the comet’s passage, with images recorded by solar-observing spacecraft. The second half of the talk will focus on how, using numerous sources of observational and modeling evidence, we are now able to paint a coherent and very compelling picture of how, why, and when, comet ISON was catastrophically destroyed as it approached the Sun on Thanksgiving Day, 2013.
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