Today in Science: Shooting star weekend

Science, insight, inspiration August 11, 2023: Humans have an innate sense of numbers, the Perseid meteor shower is peaking this weekend and what's causing record-breaking hail. Happy Friday! —Andrea Gawrylewski, Chief Newsletter Editor TOP STORIES Number Sense Most people can look at two groups of items–say, dots in groups–and pick which is the bigger group. In recent experiments with 400 people, participants could distinguish 30 versus 20 dots nearly every time. For 20 versus 21 dots, they were right nearly 60 percent of the time. And even in the hardest comparison—50 versus 51 dots—participants consistently answered correctly on 51.3 percent of trials. Why this is cool: Humans have an innate sense of numbers and values, which has even been shown to be true in infants and babies.  What the experts say: "If you are asked to make a judgment about which of two groups contains more stuff, and you have a little bit of intuitive feeling that one of them is more than the other, you should trust your gut," says study lead author Emily M. Sanford, a cognitive scientist at the University of California, Berkeley. Meteors on the Way This weekend will be the peak of the Perseid meteor shower, when dozens of shooting stars will be visible each hour. The Perseids are actually visible from mid-July, but this weekend will be their highest frequency.  How it works: Meteors in showers are small bits of material shed by a comet –the Perseid's parent body is Comet 109P/Swift-Tuttle, which is about 25 km across. Its plane of orbit in the solar system crosses our path once a year. It sheds small fragments, each only about the size of a grain of sand. They hit Earth's atmosphere at 200,000 kilometers per hour, where they compress and heat the air they encounter. The air heats up so much that it glows and rapidly vaporizes the meteoroid about 90 to 100 km above the ground. Viewing Tips: Darkness is key--getting far enough from glowing billboards and streetlights should suffice, but the darker the better. The best show will occur after about 2 to 3 A.M. EDT. Even at its peak the shower will produce only about one shooting star an hour, so a good chair or blanket to recline on is key while you wait and watch. TODAY'S NEWS • Human exposure to wildfires in the U.S. more than doubled in the past two decades. Here's what's driving it (4 min read). And here's how wildfires kill people (7 min read). • Russia has launched an uncrewed spacecraft to the Moon's south pole—its first lunar mission in 47 years. | 5 min read •Record-breaking hailstones, some more than twice the size of a softball, have been falling lately. Researchers are trying to determine whether global warming is to blame. | 5 min read •This gambling strategy will probably make you money, but you shouldn't use it, says our math columnist Jack Murtaugh. | 8 min read More News EXPERT PERSPECTIVES • Fear-mongering warnings that AI will bring about the extinction of humans distract from much-needed real research on the dangers of the technology, write Emily M. Bender and Alex Hanna. Bender is a professor and researcher of computational linguistics at the University of Washington. Hanna is director of research at the Distributed AI Research (DAIR) Institute. "We urge policymakers to instead draw on solid scholarship that investigates the harms and risks of AI," they write. | 5 min read More Opinion ICYMI (Our most-read stories of the week) • DeSantis's Florida Approves Climate-Denial Videos in Schools | 7 min read • What Caused Maui's Devastating Wildfires? | 3 min read • Red Meat Allergy Caused by Tick Bite Is Spreading—And Nearly Half of Doctors Don't Know about It | 8 min read IMAGE OF THE DAY Credit: Dan Coe (STScI/AURA for ESA, JHU), Brian Welch (NASA-GSFC, UMD) This image from the James Webb Space Telescope's NIRCam (Near-Infrared Camera) instrument reveals new details about the most distant known star in the universe, Earendel (the dot of light in the zoomed-in inset). Earendel's color shows it to be a massive B-type star more than twice as hot as our sun, and also hints at the presence of a smaller companion star.  In my experience, finding a mountaintop or hilltop with a good clearing as far from towns and cities as possible is the best recipe for seeing lots of "shooting stars." Fingers crossed for a couple clear nights this weekend! Tell me how many you spot! And send any feedback about this newsletter to: newsletters@sciam.com. See you Monday. —Andrea Gawrylewski, Chief Newsletter Editor Subscribe to this and all of our newsletters here. Scientific American One New York Plaza, New York, NY, 10004   Support our mission, subscribe to Scientific American here   Unsubscribe Email Preferences