It turns out the ‘Spiders from Mars’ are not only the name of David Bowie’s band in the well-known concept album from 1972, but are real-life geological features etched across the surface of the red planet.
Troughs across the surface of Mars that eerily resemble the eight-legged bugs have been captured in a stunning Nasa satellite photograph.
Dubbed araneiforms for their arachnid-like appearance, they are a type of land erosion where networks of cracks form on Martian soil, completely different to anything seen on Earth.
Troughs across the surface of the red planet (pictured) eerily resemble the eight-legged bugs, stunning Nasa satellite images have revealed. Dubbed araneiforms for their arachnid-like appearance, they are a type of land erosion where networks of cracks form on Martian soil, completely different to anything on Earth
Scientists from the University of Arizona located the strange features using the Hirise (High Resolution Imaging Experiment) camera aboard Nasa’s Mars Reconnaissance Orbiter (MRO).
Volunteers working on behalf of Planet Four – an online project hosted by Zooniverse, the world’s largest and most popular people-powered research platform – helped to make the discovery.
Planet Four trawls through images of the southern polar region of Mars in an effort to uncover formations called fans and blotches.
These could point to signs of water on the surface of the red planet, one of the main goals of the MRO.
Their efforts assist the team behind the orbiter in directing their search to specific locations, where they can then capture more detailed images.
‘As part of the Planet Four citizen science effort, volunteers searched Context Camera images for possible new locations on Mars with “spiders,” or features with radial troughs from which fans emanate in the springtime,’ a spokesman for the group said.
‘We planned this HiRISE image over one such location, to verify that they are spiders. There are thousands of them in this image.’
Araneiforms occur at the planet’s South Pole and form when carbon dioxide turns to ice during the Martian winter.
As the seasons change, direct sunlight penetrates the translucent ice, warming the land beneath.
The land surface then gets eroded as the gas races out and rips off little bits of dirt, forming spindly branches which resemble spider legs.
This is not the first time that these ‘Martian spiders’ have been spotted from orbit above the planet.
Citizen-science volunteers from Planet Four spotted the formations in other areas of the Martian polar surface back in August 2017. The sightings were later confirmed using Hirise.
A high resolution image from the Hirise camera onboard Nasa’s Mars Reconnaissance Orbiter of one of the new Martian araneiform ‘spiders’
WHAT IS THE MARS RECONNAISSANCE ORBITER?
The Mars Reconnaissance Orbiter (MRO) searches for evidence that water persisted on the surface of Mars for a long period of time.
It was launched August 12, 2005, and achieved an initial orbit around the red planet on March 10, 2006.
In November 2006, after five months of, it entered its final science orbit and began its primary science phase.
Since its arrival, MRO and its High Resolution Imaging Science Experiment (HiRISE) telescope have been mapping the martian surface, which has been taking shape for more than three billion years.
MRO’s instruments analyse minerals, look for subsurface water, trace how dust and water are distributed in the atmosphere, and monitor daily weather in support of its science objectives.
MRO’s missions have shown that water flowed across the Martian surface, but it is still unknown whether water persisted long enough to provide a habitat for life.
Planet Four: Terrains started in June 2015, and was one of the first citizen science projects to launch using the Zooniverse’s Project Builder platform.
Led by Professor Chris Lintott of the Department of Astrophysics at Oxford University, the Zooniverse now hosts over 100 projects.
The online platform runs on support from volunteers, of whom there are now over 1.6 million worldwide.
The volunteers act as armchair scientists, helping the team with their online research from their own homes.
More than 10,000 citizen scientists have contributed to the ‘spider’ research so far, viewing and classifying over 20,000 images derived from observations made by the Context Camera (CTX), aboard the Mars Reconnaissance Orbiter.
These images contained many spiders as well as other land forms known as ‘Swiss cheese terrain’, and craters.
The troughs are believed to be formed by gas flowing beneath the seasonal ice to openings where the gas escapes, carrying along dust from the surface below.
Dr Meg Schwamb, from the Gemini Observatory and lead author of a previous paper on the subject, said: ‘This was a totally unexpected find. By having so many eyes scouring the images, we know now that the SPLD is not the only place where spiders form. This will help us better understand the carbon dioxide jet formation process.
‘The carbon dioxide jet process that forms ‘spiders’ is a completely un-Earthly phenomenon.
‘The only other body suspected of having these jets is Neptune’s moon Triton.
‘By studying these spiders and jets we’re learning more about how Mars differs from Earth.
‘The jet process is linked to the Martian seasons and is returning carbon dioxide to the atmosphere, studying these new locales will give new insights into the Martian atmosphere.‘
Based on these exciting new results, the hunt for Martian spiders continues. ‘We have added new CTX images of Mars’ South Polar region to the Planet Four: Terrains website in need of review to see how far north these features may extend,’ Dr Schwamb added.
Nasa has previously revealed a stunning image of springtime on Mars.
Since 2006, the Mars Reconnaissance Orbiter has been charting the red planet’s terrain. This image shows defrosting of the crests of ‘Inca City’. This is the informal name given to a set of intersecting ridges that are located among the layered materials of the south polar region of Mars. Their origin has never been understood
The radial troughs have been referred to as spiders, simply because of their shape, and are caused by the thawing of carbon dioxide ice.
‘Mars’ seasonal cap of carbon dioxide ice has eroded many beautiful terrains as it sublimates (goes directly from ice to vapor) every spring,’ said Nasa.
‘In the region where the Hirise camera on Nasa’s Mars Reconnaissance Orbiter took this image, we see troughs that form a starburst pattern.
‘In other areas these radial troughs have been refered to as spiders, simply because of their shape.’
In this region the pattern looks more dendritic as channels branch out numerous times as they get further from the center.
The troughs are believed to be formed by gas flowing beneath the seasonal ice to openings where the gas escapes, carrying along dust from the surface below.
The dust falls to the surface of the ice in fan-shaped deposits.