Washington: A strong ultraviolet-wavelength absorber has been discovered on the surface of Pluto, indicating the possible presence of complex hydrocarbon and/or nitrile molecules on the planet, a new study has revealed.
Such chemical species can be produced by the interaction of sunlight or cosmic rays with Pluto’s known surface ices, including methane, carbon monoxide and nitrogen.
“This is an exciting finding because complex Plutonian hydrocarbons and other molecules that could be responsible for the ultraviolet spectral features we found with Hubble may, among other things, be responsible for giving Pluto its ruddy color,” said Dr. Alan Stern, lead author of the project.
The team also discovered evidence of changes in Pluto’s ultraviolet spectrum compared to Hubble measurements from the 1990s. The changes may be related to differing terrains seen now versus in the 1990s, or to other effects, such as changes in the surface related to a steep increase in the pressure of Pluto’s atmosphere during that same time span.
“The discovery we made with Hubble reminds us that even more exciting discoveries about Pluto`s composition and surface evolution are likely to be in store when NASA`s New Horizons spacecraft arrives at Pluto in 2015.”
The study was recently published in the Astronomical Journal.