Spiders

In 1973, a unique study on the effect gravity plays on spiderweb construction was conducted. Garden spiders (Golden orb spider to be exact) normally use gravity for orientation when building the long strands of fiber that radiate from the web’s center. When the spider lets go of a strand during construction of the web, a spider will usually drop to another portion of the web to resume construction. In zero gravity, the spider will let go of a strand and just float stationary and must regain its sense of orientation to continue construction. Scientists wanted to test how spiders would adapt in a zero-gravity environment.

To test this phenomenon, two female European garden spiders named Arabella and Anita were apart of an experiment on the Skylab 3 mission. The project was proposed by Judy Miles, a student from Lexington, Massachusetts and conducted by astronaut Owen Garriott. The two spiders were place in a window frame-like container and were monitored with a camera to record their behavior. The spiders struggled with the zero-g environment, taking a full day to adjust to the new conditions to just put together a partially constructed web. Over the course of a few days additional water and food were provided to the spiders to help monitor other variables like hydration and nutrition. With additional water, the spider constructed another web, but more elaborate. Shortly thereafter the spiders died.

Since Skylab, two additional tests have been done investigating the effect zero gravity has on spiderweb construction, both on the International Space Station in 2008 and 2011. During these three test campaigns, scientists discovered the webs constructed in space were finer than normal Earth webs. Additionally, various locations throughout the web were thicker and thinner in contrast to webs constructed on Earth which have uniform thicknesses throughout. Below is Arabella first partially constructed web.

 Courtesy of NASA

Courtesy of NASA

Cats

Spiders aren’t the only creature tested in zero gravity. NASA sent cats up on its Vomit Comet in the 1960s to better understand how the best internet meme can handle trying to land in zero gravity. It’s universally understood that cats can consistently land on their feet, mainly because can use their own body as a flexion. Meaning cats will pivot the front have of their body, from the waist to the face, independently from the back portion of their body. Then the back portion of the body will follow soon after, with their tail circling at the end as correcting force. Scientists were curious how cats would behave free fall knowing their earth-like free falling behavior. The result of the study is best understood with the video below, enjoy.

Cat falling.jpg

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