Ziggy played guitar, and researchers in the UK played with a large piece of dry ice to try to figure out what lies behind the strange alien patterns known as “spiders on Mars. “
These patterns, which are visible on satellite images of the south pole of the red planet, are obviously not real spiders; but the branched, black figures carved into the surface of Mars look eerie, scientists called them “araneiforms” (meaning “spider-like”) after discovering the figures more than two decades ago.
The giant shapes measure up to 3,300 feet (1 kilometer) and look like nothing the earth. But in a new study published March 1
“This research presents the first set of empirical evidence for a surface process thought to alter the polar landscape. March, “lead study author Lauren McKeown, a planetary scientist at Open University in England, said in a statement. “The experiments show directly that the spider patterns we observe on Mars from orbit can be cut out by directly converting dry ice from solid to gas.”
The Martian atmosphere contains more than 95% carbon dioxide (CO2), according to NASA, and so much of the ice and frost that forms around the planet’s poles in winter is also made of CO2. In a 2003 survey, scientists assumed that spiders on Mars could form in the spring when sunlight penetrates the translucent layer of CO2 ice and warms the earth beneath. This warming causes the ice to sublimate itself from its base and builds up pressure under the ice until it finally cracks. Pent-up gas escapes through the cracks in a bubbling cloud, leaving the zigzagging spider leg patterns visible on Mars today, the team assumed.
Until recently, scientists had no way to test this hypothesis on Earth, where atmospheric conditions are very different. But in the new study, scientists made a small piece of Mars here on Earth using a device called the Open University Mars Simulation Chamber. The team placed sediment grains of different sizes inside the chamber and then used a system similar to a claw machine you would see in a local arcade to suspend a block of dry ice over the grains. The team adjusted the chamber to mimic Mars’ atmospheric conditions and then slowly lowered the dry ice block onto the grains.
The experiments proved that the hypothesis of spider sublimation is valid. Regardless of the size of the sediment grains, the dry ice always sublimated on contact with them, and the escaping gas pushed upward, cutting out spider-like cracks along the way. According to the researchers, the spider bones branched off more when the grains were finer and smaller when the grains were coarser.
Although not definitive, these experiments provide the first physical evidence to show how spiders on Mars may have formed. Is not it so sublime.
Originally published on WordsSideKick.com.