Syrtis Major

Syrtis Major, is the Roman name for the Gulf of Sidra on the coast of Libya (classical Cyrenaica).

Syrtis Major (named after the terrestrial surface feature) is a "dark spot" located in the boundary between the northern lowlands and southern highlands of Mars. It was the first surface feature of another planet to be named, by Christiaan Huygens in 1659.

They are several theories about its formation. In the past, some have guessed that is liquid water, even though the temperatures and the air pressure seem to prevent this possibility. The research team that worked on the ALH84001 Martian meteorite from Antarctica have even suggested that they are bacterial growths, feeding off geothermal vents.