This panorama was captured in 2005 as the Huygens probe plummeted through the thick
nitrogen atmosphere of Titan, Saturn's largest moon.
Having shown that chemically modified magnetite (Fe2CrO4) meets the basic criteria required for an air stable, visible light photocatalyst, the investigators plan to carry out experiments in which they will transfer freshly grown Fe2CrO4 surfaces to a photoelectrochemical cell under a
dry nitrogen atmosphere to avoid picking up surface carbon contamination.
The team modified this model for extraterrestrial forecasting by considering two potential atmospheres: an Earth - like one rich in nitrogen and oxygen, and a
simple nitrogen atmosphere containing trace amounts of CO2.
Two worlds, other than the Earth and Pluto, have
nitrogen atmospheres, but they are moons rather than planets: Titan, Saturn's biggest moon, and Triton.
In the weak sunlight illuminating Pluto, some of the nitrogen ice must vaporise to produce
a nitrogen atmosphere around the planet.
Maureen Palmer at NASA's Goddard Space Flight Center in Maryland and her colleagues detected traces of vinyl cyanide in Titan's
nitrogen atmosphere.
Titan maintains a high pressure (> 1 bar)
nitrogen atmosphere and an active hydrological cycle driven not by water, as on Earth, but by hydrocarbons.