February 23, 2025Measles Outbreaks, Asteroid Risks and Fish FriendsIn this weeks news roundup, we cover activity from the black hole at our galaxys center and a troubling measles outbreak in Texas. Anaissa Ruiz Tejada/Scientific AmericanSUBSCRIBE TO Science Quickly[CLIP: Theme music]Happy Monday, listeners. For Scientific Americans Science Quickly, this is Allison Parshall filling in for Rachel Feltman. Lets get the week started by catching up on some of the latest science news.[CLIP: Without Further Ado by Jon Bjrk]On supporting science journalismIf you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.First, a quick update on our favorite ominous asteroid. The rock dubbed 2024 YR4 briefly had an even higher probability of hitting Earth than the last time we mentioned it. Early last week, NASA pegged the rocks chances of smashing into us in 2032 at more than 3%. That was the highest impact probability ever recorded for an asteroid of its size or larger. But you can relax because as of last Thursday, that estimate had fallen back down to a reassuring 1.5%.Its totally understandable if you find all this wishy-washyness a bit disconcerting. But rest assured that things are playing out more or less exactly the way scientists have told us to expect. For more information on 2024 YR4and why its chances of hitting us keep changing so rapidlycheck out our February 12 episode.[CLIP: Sound transition]And speaking of space: new observations from the James Webb Space Telescope suggest that the black hole at the center of our galaxy is having something of a constant cosmic rager.Sagittarius A*, which is the black hole that sits at the center of the Milky Way, our galaxy, is apparently emitting flares of light pretty much all the time. The black holes accretion disk, which is that swirl of gas and dust that surrounds it, seems to be always bubbling with random bursts of activity, from like the brieest of faint flickers to bright daily eruptions. And based on observations taken in 2023 and 2024, the black hole doesnt ever seem to settle into a steady state, according to the researchs lead author. The scientists hope to continue studying Sagittarius A* with JWST so they can learn more.[CLIP: Sound transition]In other space news, for the first time, an astronaut candidate with a physical disability has been cleared to go to the International Space Station. John McFall had his right leg amputated above the knee following a motorcycle accident when he was 19. He's a Paralympic medalist and an orthopedic surgeon, and in 2022 he joined the European Space Agency, or ESAs reserve astronaut corps.The ESA conducted an extensive feasibility study to prove there were no medical or technical reasons to keep McFall from going into orbit. He isnt guaranteed to get assigned to an ISS mission. But he told the Guardian that thanks to the detailed and methodical nature of the ESAs study, the agencys international partners have accepted his eligibility to fly.[CLIP: Sound transition][CLIP: It Doesnt End Here (Instrumental), by Nehemiah Pratt]Now lets catch up on some health stories. A troubling measles outbreak continues to grow in West Texas, with some 58 cases identified as of last Tuesday, according to the state health department. Measles is highly contagious and can be fatal. And in this outbreak, most of the cases have been reported in children and young adults.The U.S. Department of Health and Human Services says 95 percent of children in kindergarten should be protected with two doses of the MMR vaccine to prevent measles outbreaks. In Gaines County, which is the epicenter of the Texas outbreak, nearly 20 percent of incoming kindergarten students for the 2023-2024 school year were unvaccinated. The U.S. as a whole has fallen short of the 95 percent vaccination threshold for several years now.[CLIP: None of my Business by Arthur Benson]Lets wrap things up with some fascinating animal research.First, a recent study could help explain why humans have such unique powers of speech. In a paper published last Tuesday in Nature Communications, scientists reported that a gene variant specific to modern humans may have played a role in the development of language.Modern humans have a unique variant of a gene called NOVA1, compared to Neanderthals and Denisovans. Previous research has suggested that this variant can impact brain development.In the new study, researchers used CRISPR gene editing to swap the NOVA1 gene typically found in mice with the modern human variant. When the mice with the swapped gene vocalized, they made slightly different sounds than their counterparts.While the development of human speech is probably tied to many different genes, researchers say that they hope this study will help us better understand the evolution of languageand perhaps allow us to improve our detection of and intervention in human speech-development issues.Meanwhile, a study published last Tuesday in Biology Letters suggests that fish really can be our friends. Researchers diving in the Mediterranean Sea have noticed that local fish seem to pick up on which scientists carry food to use as experimental rewards. The fish apparently have a tendency to follow divers whove previously offered snacks while ignoring their colleagues, so scientists decided to try and figure out whether wild fish can actually recognize individual humans.The researchers started by training fish to follow one diver in particular. She initially wore a bright-red vest during her dives and offered just tons of snacks. Eventually, even wearing plain diving gear, hiding the food and only feeding fish after they followed her for 50 meters [roughly 164 feet], she had about 20 saddled sea bream and black sea bream that knew her and swarmed her once she hit the water.Then, to make a long story short, the scientists demonstrated that fish could learn to distinguish her from a colleagueat least when they were wearing distinctive gear. That suggests some fish at least can pick up on visual cues to tell humans apart.So if youre certain that your goldfish adores you specifically, dont let anyone tell you otherwise.Thats all for this weeks news roundup. Rachel will be back on Wednesday to tell you all about an unsung hero in our quest to understand the cosmos.[CLIP: Theme music]Science Quickly is produced by me, Allison Parshall, Rachel Feltman, Fonda Mwangi, Kelso Harper, Madison Goldberg, Naeem Amarsy and Jeff DelViscio. Shayna Posses and Aaron Shattuck fact-check our show. Our theme music was composed by Dominic Smith. Subscribe to Scientific American for more up-to-date and in-depth science news.For Scientific American, this is Allison Parshall filling in for Rachel Feltman. Have a great week!