July 8, 2011
The four astronauts aboard the space shuttle Atlantis will not be alone when they blast into space today (assuming the launch proceeds as scheduled). The last shuttle mission will also carry 30 mice that are part of an experiment to better understand why astronauts lose bone mass when they hang out in low-Earth orbit.
The mouse study is typical of the type of research that seemed to dominate space shuttle science: investigations devoted to figuring out how the human body—and the microbes that parasitize us—cope with space. It’s the kind of work that’s necessary if we want to safely send people on long-term missions to Mars and beyond.
With all of the talk about the end of the space shuttle program, I wondered what other science has happened aboard Atlantis, Challenger, Columbia, Discovery and Endeavour. I found some surprises. Here are my favorite quirky space shuttle science projects:
A rose in space smells as sweet—or sweeter: The fragrance of flowers comes from the plants’ essential oils. Many environmental factors influence the oils that a flower produces—and one of those factors is apparently gravity. In 1998, the perfume manufacturer International Flavors & Fragrances sent a small rose called Overnight Scentsation into space aboard Discovery. Astronauts grew the rose in a special chamber and collected its oils. In the low-gravity conditions of Earth’s orbit, the flower made fewer essential oils, and the oils it did produce smelled different (a “floral rose aroma” instead of “a very green, fresh rosy note”). Back on Earth, the perfume company synthesized the rose’s space oils to create a new fragrance that is now in Shiseido’s perfume called Zen.
The MGM experiment: MGM doesn’t refer to the movie studio or the Las Vegas casino; it stands for “Mechanics of Granular Materials.” With this experiment, researchers in space studied the effects of earthquakes, sort of. On three shuttle missions, the MGM experiment compressed columns of sand to allow researchers to study the sand’s strength and other mechanical properties. Such properties are relevant to many processes on Earth, such as soil liquefaction. Liquefaction is often a problem during earthquakes: the shaking increases the external forces acting on any water in the ground, causing water pressure to go up. The higher water pressure weakens the soil, making it flow like a liquid and causing buildings to sink. Studying sand in space is beneficial because the lower gravity reduces certain stresses that make it difficult to study liquefaction and similar phenomena on Earth. Sadly, the last MGM experiment flew aboard the Columbia mission that broke up during re-entry in 2003.
The Tunguska mystery solved: Technically, this piece of science didn’t occur aboard the space shuttle, but it certainly benefited from the shuttle program. In 1908, an extraterrestrial object hit Russia, flattening almost 3,500 square miles of Siberian forest near the Podkamennaya Tunguska River. Scientists have debated whether an asteroid or comet caused the impact. Space shuttle exhaust points to a comet. Researchers at Cornell University and Clemson University made the connection after noticing the formation of noctilucent (“night shining”) clouds following two shuttle launches. The brilliant clouds likely formed from the hundreds of tons of water vapor emitted from the shuttle’s engine during takeoff. Historical records note that the night sky similarly lit up after the Tunguska event. The researchers say noctilucent clouds were probably the cause of the glow, suggesting that whatever hit Earth must have released a lot of water into the atmosphere. This makes comets the likely culprit because they, unlike asteroids, carry a lot of ice.
These scientific experiments are fun, but do they justify the hefty price tag of the shuttle program? Probably not. Some might say the program’s greatest scientific achievements relate to the satellites that astronauts brought to space or the repairs they made to the Hubble Space Telescope.
I’ll suggest another achievement, one that’s more personal. As someone who grew up during the shuttle’s early days, the program helped steer me down a scientific path. It certainly helped foster my interest in learning about the world around (and above) me.
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