Extraterrestrial liquid water extrasolar planetary systems appear to have very different compositions to the Solar System, though there is probably sample bias arising from the detection methods. Liquid water has a distinct absorption spectroscopy signature compared to other states of water due to the state of its hydrogen bonds. Despite the confirmation of extraterrestrial water vapor and ice, however, the spectral signature of liquid water is yet to be confirmed outside of Earth. The signatures of surface water on terrestrial planets may be undetectable through thick atmospheres across the vast distances of space using current technology. Seasonal flows on warm Martian slopes, though
Solid nitrogen Solid nitrogen Solid nitrogen is the solid form of the element nitrogen. It is an important component of the surfaces of Pluto and outer moons of the Solar System such as Neptune's Triton. Under low or moderate pressure solid nitrogen contains dinitrogen molecules held together by London dispersion forces. Non-molecular forms of solid nitrogen produced by extreme pressures have a higher energy density than any other non-nuclear material. Solid nitrogen was first made in 1884, by first liquefying hydrogen with evaporating liquid nitrogen, and then allowing the liquid hydrogen to freeze the nitrogen. Karol Olszewski achieved a world record lowest