David Bowie named his backing band ‘The Spiders from Mars’ in the early 1970s.
But the rock legend certainly had no idea that this was describing a real phenomenon on our neighboring red planet.
Although not true spiders, ‘araneiforms’ are dark cracks in the Martian soil, completely unlike anything on Earth.
They are clustered around the south pole of Mars and are known as ‘Martian spiders’ because they have a distinctive spider-like shape.
New images from two European Space Agency probes – the Mars Express and the Trace Gas Orbiter – show the remarkable formations in incredible detail.
This new Mars Express image shows small, dark features on the surface known as “spiders.” These are formed when carbon dioxide gas heats up in sunlight and breaks through plates of overlying ice
Shown here is a section of the Martian surface captured by ESA’s ExoMars Trace Gas Orbiter. A rounded segment of an eroded crater basin is visible on the right. Note the numerous dark spots with tendrils that are eerily reminiscent of spiders. These are visible in large numbers on the left and irregularly distributed throughout the rest of the image
The scientific name for these features – ‘araneiforms’ – literally means ‘the shape of a spider’ in Latin.
They are formed when the spring sun hits layers of frozen carbon dioxide (CO2) on the Earth’s surface.
The sunlight causes the CO2 ice at the bottom of the solid layer to turn into gas, which then accumulates and bursts up through the overlying ice layers.
The rising gas jets, laden with dark dust, break through layers of ice up to a meter thick before falling back down and settling on the surface.
This creates characteristic ‘spider-shaped’ dark spots between 45 and 900 meters wide, which can be seen on space probe images.
“The carbon dioxide jet process that creates ‘spinning’ is a completely unearthly phenomenon,” says Dr Meg Schwamb, an astronomer at Queen’s University Belfast.
‘The jet process is linked to the seasons on Mars and returns carbon dioxide to the atmosphere.’
‘By studying these spiders and jets we learn more about how Mars differs from Earth.’
According to Dr. Schwamb, the only other body suspected of having these jets is Neptune’s moon Triton, which is known to be geologically active.
David Bowie played with his backing band The Spiders from Mars during the Ziggy Stardust era (1972). The singer recruited the band but named them after a line from his song ‘Ziggy Stardust’
Mars is the fourth planet from the sun, with an ‘almost dead’ dusty, cold desert world with a very thin atmosphere. This image of the planet was taken using the Visual Monitoring Camera (VMC) on ESA’s Mars Express spacecraft, November 10, 2023
Araneiforms were first observed more than twenty years ago, but only in 2021 did astronomers prove how exactly they form.
The researchers from Trinity College Dublin have recreated the Martian process in the laboratory by lowering and lifting blocks of frozen CO2 onto gravel beds.
Experiments have shown that the spin patterns are created by the direct conversion of dry ice from solid to gas, known as ‘sublimation’.
Such a process occurs on Mars because the planet has an atmosphere composed largely of CO2 – about 95 percent.
On Earth, meanwhile, only about 0.04 percent of the atmosphere consists of CO2; instead, most of it is made up of nitrogen (78 percent) and oxygen (20 percent).
According to the ESA, araneiforms are mainly clustered on the edge of a part of Mars nicknamed Inca City.
Inca City, better known as Angustus Labyrinthus, was discovered by NASA’s Mariner 9 probe in 1972 – the same year Bowie and the Spiders from Mars released their groundbreaking album.
Mars is shown here in shades of brown and brown. On the left are two major features: a raised network of linear, grid-like ridges and walls, known as Inca City, and a number of dark spots indicating the presence of features known as ‘spiders’.
David Bowie performing with The Spiders From Mars on the first night of the Ziggy Stardust Tour at Borough Assembly Hall in Aylesbury, Buckinghamshire on January 29, 1972. From left: Trevor Bolder, David Bowie, Mick ‘Woody’ Woodmansey and Mick Ronson
Bowie recruited the band, but gave them a new name, taken from a line from his song ‘Ziggy Stardust’ which appears on the album.
Because araneiforms were not yet known fifty years ago, Bowie took inspiration from another source: a UFO sighting in October 1954.
An Italian stadium audience thought they had witnessed a Martian spacecraft dropping a thin filament material – believed to be a web of migrating spiders.
Meanwhile, the title of one of Bowie’s most famous hits – 1971’s ‘Life on Mars’ – is said to have been inspired by intense media coverage of the race to reach the planet between the US and the Soviet Union.
As for whether there is life on Mars, scientists generally think the answer is probably not due largely to its lack of atmosphere and freezing temperatures.
The possibility that there was life on Mars is more promising, as it is thought that the planet was once covered in a lush liquid ocean.