On July 28, 1973, two all-American ladies spun into space on the Skylab 3 assignment – a solid decade before Sally Ride’s historic space shuttle Challenger STS-7 mission launch. Their monumental task: to weave some silky webs in zero gravity.

(NASA History Office)

At the prompting of Massachusetts high schooler Judy Miles, NASA space scientists (who, most likely, were not arachnophobes) asked, “How does a weightless environment affect a spider’s web-spinning?”


“After reading an article in the National Geographic magazine describing the behavior of the spider, Miles suggested a study of the spider’s behavior while weightless. Since the spider senses its own weight to determine the required thickness of web material and uses both the wind and gravity to initiate construction of its web, the lack of gravitational force in Skylab would provide a new and different stimulus to the spider’s behavioral response.” (NASA:

Arabella and Anita were a couple of crowned orb-weavers chosen to demonstrate whether or not zero-G webs were possible. As a relatively calm but inspired species of spider, the girls made the perfect fit. Armed with tiny fangs and extra appendages, NASA’s astronauts welcomed the webspinners aboard.

For the first couple of days, the spiders flailed around and swam about in their brand new environment, producing clumsy and inelegant strands of webs as the idea of weightlessness blew their itsy bitsy minds.

Arabella’s first web (NASA)

But after adjusting, Anita and Arabella went about their cages like regular Earthly arachnids, only no longer bound by something outrageous like gravity. They became unstoppable flying, eight-legged monsters, shaping their caged, window-like environment to their own whims. That is, until they passed away during the 59-day mission.

As the NASA scientists predicted, since they’re also apparently all entomologists, the webs were thinner than the ones found on Earth that are made by the same type of spider. The thickness of the silk strands in a single web, however, varied – something which is not found on Earth. This is because the spiders use their own weight to gauge how thick the webs should be, and without that ability, it’s hard to gauge just what the spider might need.

More than forty years later, Anita and Arabella are on display at the Smithsonian for tourists to stare in awe at the wonder of modern web design.

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