NASA’s search for life on extrasolar planets – those outside our solar system – is grounded in two main criteria. First, the presence of liquid water, and second the presence of oxygen in the atmosphere. To date, none with the criteria have been found, but there have been several interesting close calls. One planet in particular, in the Pegasus constellation some 150 light years from Earth, has captivated scientists.

On this day, November 27, in 2001, Planet, 209458b, nicknamed “Osiris,” was discovered with an oxygen and hydrogen, and possibly even water vapor in its atmosphere. The only catch: Osiris is evaporating.

Orbiting a star much like our own sun at an orbital distance one-eighth that of Mercury – the half-molten planet closest to the sun in our solar system – Osiris’ surface heats up to 1,000 degrees Celsius (1832 degrees Farenheit), and whirlwinds of rising hydrogen atoms sweep up oxygen along into outer space. The planet is slowly losing mass to the heat – hence the nickname, for an Egyptian god who also lost a part of his body.