Scientists Explain Why There Are ‘Spiders’ On Mars
David Bowie Was Right: There Are Spiders on Mars
David Bowie’s famous lyrics about spiders from Mars may have been more accurate than we realized. Recent images captured by the European Space Agency’s Mars Express and ExoMars Trace Gas Orbiter (TGO) reveal distinctive, spider-like shapes on the Martian surface.
These eerie formations, however, are not actual arachnids. They are small, dark features that appear when the spring sunshine hits layers of carbon dioxide that accumulated during the planet’s long, dark winter months.
This fascinating phenomenon was observed on the outskirts of an area in Mars’ southern polar region known as Inca City. The name is inspired by the linear, almost geometric network of ridges that bear a striking resemblance to ancient Inca ruins.
While not living creatures, these spider-like formations add another layer of mystery and intrigue to our understanding of Mars and its dynamic seasonal processes.
ESA says: “The sunlight causes carbon dioxide ice at the bottom of the layer to turn into gas, which subsequently builds up and breaks through slabs of overlying ice. The gas bursts free in Martian springtime, dragging dark material up to the surface as it goes and shattering layers of ice up to a meter thick.”
The emerging gas, heavy with dark dust, erupts through cracks in the ice, forming tall fountains or geysers. These then fall back down and settle on the surface, creating dark spots ranging from 45 meters to 1 kilometer across.
According to the European Space Agency (ESA), “This same process creates characteristic ‘spider-shaped’ patterns etched beneath the ice – and so these dark spots are a telltale sign that spiders may be lurking below.”
So, Mars Express has revealed a great deal about Mars in the last two decades and counting. The orbiter continues to image Mars’s surface, map its minerals, explore the composition and circulation of its atmosphere, probe beneath its crust, and study the Martian environment.