Maybe you saw the news: this week, we humans intentionally crashed a space probe into Saturn at the end of the spacecraft’s 13-year mission to photograph and gather data about Saturn and its moons. The probe, Cassini, has sent amazing images like this one back to us here on Earth, illuminating our understanding of Saturn and its neighborhood like never before:
That little pale blue dot where the added arrow is pointing? That’s us, Earth, shining in the shadow of Saturn. I love this picture, both for its amazing view and how it illustrates the scale of our solar system. Thanks to Cassini, we have also discovered new properties of some of the moons of Saturn, including geologic activity, and potentially water or methane-rich habitats. Maybe alien microbes call those moons home. We don’t know, and Cassini didn’t have any way to find out. So when we finished Cassini’s mission–extended by years already–its keepers decided to incinerate the space probe in Saturn’s atmosphere, rather than let it careen around Saturn’s neighborhood and potentially disturb these amazing worlds far from our own home. The Cassini mission, and the passionate work conducted by a large team of scientists for over two decades, is inspiring. I’m so glad they shared the wonder of Cassini’s findings with us, and I hope we get to go back and learn more.
Meanwhile, here on Earth, we’ve had a busy and tragic couple of weeks in the Caribbean and North America. Hurricanes in the Atlantic Ocean, an earthquake in Mexico, wildfires in the American west… Mother Nature was overwhelming in her power, and we have endured the results, helped friends and strangers, and pondered our own predictive skills in the face of a changing climate. But in the midst of the water, the wind, the fire, and the destruction came a small science story…about cats. Perhaps you know this story’s background: famed author Ernest Hemingway once had a cat with six toes when he lived on the island of Key West, off the southern tip of the Florida mainland. The cat’s descendants continue to live on the island today. Most have more than the standard allotment of toes, and their presence on the island of Key West is as famous as its restaurants and vacation lifestyle. Cared for by managers of the Hemingway Home, a museum and visitor attraction, the cats roam the island and entertain the tourists. But with hurricane Irma bearing down on the Florida Keys and evacuations in place, what would happen to the cats? Some intrepid staffers remained on site to corral the cats and care for them in the face of the hurricane, come what may. Key West ultimately was spared the worst of the storm, and the cats, staff, and museum all escaped with lives and structures intact.
The Hemingway cats are an interesting science story of their own. They have a genetic condition called polydactyly, which is a dominant trait that gives rise to those extra toes. Polydactylous cats (or humans) need to inherit a copy of that gene variation from only one parent to have the condition; the island conditions on Key West have given rise to a large population of cats with this trait, which makes them a curiosity. Not all of the cats have extra toes, however, because the trait isn’t always expressed, a genetic quirk called incomplete penetrance. It’s an interesting little point of genetics tucked into an island paradise. Yet islands are vulnerable, as we’ve seen, and the fate of the cats and their gene pool was not guaranteed. Such is life on the tiny blue dot of planet Earth.
From the grandness of space to a small population of cats on a tiny island in the ocean, with winds and rain and fire and geologic activity shaking things up… it’s been quite a ride recently. I’ve been reading the news and thinking of those impacted by the devastation of forces stronger than our engineering; fortunately, the storms haven’t crushed the human spirit of resiliency. Our own place in history and in the cosmos is tiny, yet the human condition is inspiring. I’m always looking for new science stories that help us refine and expand our understanding of the world around us, and our place in it. Let’s see what the next week brings!