European Space Agency’s Trace Gas Orbiter (TGO) has detected a tinge of green in the atmosphere of Mars. It is for the first time this green glow has been spotted around a planet beyond Earth.
This faint green glow in sky is caused by the interaction between sunlight and oxygen in the upper atmosphere. This new discovery in the Martian atmosphere will help in unveiling the facts behind the processes that drive airglow, both on Earth and elsewhere.
Study lead author Jean-Claude Gérard, said, “One of the brightest emissions seen on Earth stems from night glow. More specifically, from oxygen atoms emitting a particular wavelength of light that has never been seen around another planet,”
Astronomers have been looking for this green glow for decades
Scientists have predicted this phenomenon to occur on Mars for around 40 years. But now TGO help them found it.
While taking some stunning from International Space Station, astronomers discover that the trick is all in the viewing angle. It was easier for them to spot this green airglow around Earth while looking towards the horizon, rather than looking directly down.
Therefore European Space Agency’s team applied the same trick to Mars. They adjusted the angle of the ultraviolet and visible spectrometer (UVIS), an instrument on the TGO.
Ann Carine Vandaele, co-author of the study, said, “Previous observations hadn’t captured any kind of green glow at Mars, so we decided to reorient the UVIS nadir channel to point at the ‘edge’ of Mars, similar to the perspective you see in images of Earth taken from the ISS,”