In 1973, NASA Launched Two Spiders into Space for a Unique Mission – Here’s What They Discovered

Long before robots explore Mars or humans dream of installing colonies on the Moon, scientists have chosen to entrust a spatial experience to one of the most discreet animals on our planet. In 1973, two spiders were sent aboard the Skylab station to answer a question as simple as it is. They unsuspected capacities of the animal brain.

An idea born in an American high school propels two spiders into space

Judith Miles, a high school student in Lexington, Massachusetts, probably did not expect to see her idea retained by NASA. Inspired by an article by the National Geographic on animal behavior, she proposed to observe the capacity of spiders to build a canvas in impictors. This initiative was selected as part of the educational program on board Skylab, the first American space station.

The Skylab 3 mission launched in space on July 28, 1973, two Araneus Diadematus females – Arabella and Anita. The astronauts Alan Bean, Jack Lousma and Owen Garriott, in charge of the experience, installed them in cages specially designed to allow them to forge their canvases. NASA reports that the teams fueled the two spiders before the launch and placed them in bottles containing a water saturated with water, in order to guarantee their survival during the mission.

Aboard Skylab, surprisingly adaptive behavior

From their installation in space habitat, the reactions of the spiders were observed closely. Arabella, the first to enter, initially produced an incomplete, rude, barely structured canvas. The next day, however, she managed to weave a real circular trap, showing rapid adaptation to the environment without gravity.

Anita's introduction to mid-mission enabled this adaptability to confirm. Astronauts prolonged the experience by nourishing Arabella with a rare cute net and by moistening its environment more. After a phase of hesitation, the spider consumed part of its own canvas, then rebuilt another, better structured, testifying to a progressive acclimatization to the spatial conditions.

The death of the two spiders during the mission, probably due to dehydration, did not prevent the scientific success of the experience. The canvases collected on their return to earth made it possible to identify a notable modification. The silk woven as a weightlessness was significantly finer than a land condition, a revealing index of the fundamental role played by gravity in engine calibration.

What weightless spiders reveal from the animal brain

Behind this simple net hanging in a box hides a precious indicator of brain operation. As the Marshall Space Flight Center of NASA explains, the geometry of the canvas reflects the state of the central nervous system of the animal. Building a symmetrical and functional trap implies fine motor capacities, a perception of the environment and a precise spatial memory.

In the absence of gravity, the weightless spider could no longer trust the classic landmarks that guide the construction of its canvas, like its own weight or the sense of the wind. However, despite this sensory disturbance, she managed to reprogram her behavior, probably based on other stimuli such as the light or the texture of the support.

This result has paved the way for other studies, especially aboard the ISS. The Air and Space museum recalls that more recent experiences have observed an increased symmetry of canvases in space, a remarkable behavioral adjustment for an organism that has never evolved out of its terrestrial ecosystem.

What these spiders have demonstrated goes beyond the framework of ethology. They have proven that the living organism, even simple, has sufficient plasticity to reshape its motor responses in radically new contexts. A precious lesson to consider the future of inhabited space missions.