the mystery of the martian ball

Would the Martians convert to knitting? While aliens are unlikely to make themselves a scarf in anticipation of winter, the crazy theory has sparked mockery on the internet in recent days. At the origin of this funny story, a photo of Mars published by NASA on Tuesday July 12 showing, placed on sand, an object resembling a ball of tangled yarn. Other teasing social media users liken the unidentified threads to a plate of spaghetti.

The snapshot was taken by the rover Perseverancethe explorer robot on mission on the red planet since April 2021. “There are a lot of uncertainties” as to the nature of the object, a NASA spokesman told AFP.

A parachute cord

The most plausible explanation is actually quite down to earth: it could be pieces of the rope connecting the rover to the parachute that was used to slow its descent during its landing. Or to the one used to lower it during the last meters (a stage called “sky crane”).

“It can be assumed that these small pieces of debris were moved by the wind after landing”, explains the NASA spokesperson. And they are probably still moving: a few days after the photo of the wires, the robot went back to the same place, but they had disappeared.

Perseverance has already found himself face to face several times with the equipment that allowed him to land on Mars. In June, another photo showed what at first glance looks like a piece of aluminum foil, wedged between two red stones. It was actually a piece of thermal insulation from the descent stage (also used for the “sky crane”).

old lake

All of these images were captured by the rover in the delta of an ancient river, which scientists believe flowed into a huge lake billions of years ago, and where Perseverance searches for traces of ancient life.

In place of the now disappeared lake stands the Jezero crater, where the rover landed in February 2021. This is where he was able to photograph, in April, the parachute itself. The small helicopter on board for the trip, called Ingenuity, for its part captured even more impressive images in flight: not only the parachute, but also the rear shield which contained the latter before its deployment. Pictures that can “help enable safer landings in the future”NASA commented at the time.

Other misleading clichés

Other photos taken on Mars revealed singular images. On May 7, Perseverence had thus immortalized a rock in which was dug a cavity suggesting a doorway. The photo quickly went viral on Twitter and the explanation for this phenomenon was quick: it would actually be a natural fracture in the rock, possibly caused by a landslide, according to NASA scientists. A hypothesis confirmed by the publication of a wide shot image.

A year earlier, in April 2021, Perseverence, who was just beginning the exploration of the planet closest to Earth, took a picture of a rock on which many people thought they saw a man lying. So much so that a ufologist (a person who studies unidentified space objects) tried to prove on his YouTube channel the presence of a human on Mars.

It was really just an optical illusion called pareidolia, a bias that involves associating an ambiguous visual stimulus with an identifiable item, often a human or animal form. Illusions of this type have been observed on other Martian images, suggesting in turn the presence of a spoon, a face, Greek statues, plastic waste and even… a squirrel.