It lived for more than four billion years in the fringes of the solar system before a passing star would change its destiny, sending it on a fatal course toward the sun.

Some thought Comet ISON would survive its close brush with the sun, emerging to produce a spectacular show for the Northern hemisphere's December evenings. But it wasn't to be.

And now it's officially an ex-comet. It even has an obituary, written by astrophysicist Karl Battams, who works at the Naval Research Laboratory. People think obituaries are sad, but often they are fascinating and educational, especially when the subject was billions of years old.

Dr. Battams had been studying this comet since it was discovered moving toward the sun in September of 2012. In a NASA press conference before the holiday weekend, Battams gave it less than 50/50 odds of surviving, but he said he was still thankful that he had the opportunity to study it.

Tragically, on November 28, 2013, ISON's tenacious ambition outweighed its ability, and our shining green candle in the solar wind began to burn out.

RIP Comet ISON.