Discovering the top of the world is even higher

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THIS JUST IN: NASA announces the selection of 18 astronauts—nine of them women—to train for the first crewed U.S. missions to the moon in 48 years. (We'll have more on this further down in the newsletter).

By Victoria Jaggard, SCIENCE executive editor

Measuring Everest: There’s something endlessly alluring about antique instruments of science. Maybe it’s my inner steampunk fan coming through, but I can’t get enough of the gleam of brass and the delicate flourishes found on old sextants, orreries, and chronometers. Heck, I even have a tattoo of a 17th-century brass astrolabe. Many of these sumptuous tools have fallen out of fashion as humans have invented ever more precise ways of navigating the world around us, trading brass for lightweight plastic or even swapping analog devices for more advanced digital methods.

That’s why I was delighted to find out that at least one recent expedition went a little old-school: To make a comprehensive measurement of the height of Mount Everest (above), scientists combined cutting-edge GPS and satellite data with more traditional survey data from instruments called theodolites.

Variations on this instrument (above) have been around since the mid-1500s, according to the Smithsonian National Museum of American History. It’s basically a rotating telescope mounted on a tripod that allows a user to measure the angles between two points. Early attempts to measure Everest in the 1800s used theodolites such as the half-ton instrument pictured above, requiring surveyors to lug heavy gear as they zig-zagged their way north from the Bay of Bengal, Freddie Wilkinsonreports for Nat Geo. Until this week, the official height recognized by the government of Nepal was 29,028 feet above sea level—a number calculated in 1954 using a similar method.

To get the new height of 29,031.69 feet above sea level, teams from Nepal and China used GPS and ground-penetrating radar. But they also “waited at eight sites with views of Everest’s summit to fix its elevation at sunrise, when the atmosphere is most clear, with modern laser theodolites,” Wilkinson reports. To my eye, these instruments are not as aesthetically pleasing as a 19th-century device. But even if we’ve sacrificed form over function, it’s a testament to the theodolite that it still has a place in 21st-century science.

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Today in a minute

Narrowing the roster: Who will be the first woman on the moon? NASA today selected 18 astronauts to train for its first astronaut missions to the moon since 1972. Nine of them are women, making it possible that one of them will become the first woman to walk the lunar surface. “If I can be a part of these missions in any capacity, it will truly be a dream come true,” says Jessica Meir, who already has logged more than 200 days in space aboard the International Space Station. Pictured above are 9 of the 18 astronauts, left to right from top left: Stephanie Wilson, Jessica Meir, Jonny Kim, Kate Rubins, Kjell Lindgren, Nicole Mann, Victor Glover, Raja Chari, Jasmin Moghbeli. Read more here.

Vaccine update: Britain began vaccinating residents over 80 years old on Monday, and these elders gave common-sense answers for their desire to move past a virus that has killed a reported 1.55 million people since February. “I’ve got granddaughters, and I want to live a long time to enjoy their lives,” Martin Kenyon, a just-vaccinated 91-year-old Londoner told CNN. In the U.S., an FDA analysis says that Pfizer’s vaccine is safe and offers strong protection against COVID-19 within 10 days of the first dose, Nat Geo’s Amy McKeever reports.

Volcanic giant? A preliminary analysis of several volcanic islands off the southern coast of Alaska indicates they might actually form a single eruptive behemoth. If their suspicions are confirmed, researchers believe that an underwater basin may have resulted in the Aleutians from a volcanic explosion that was just shy of earning the label “super eruption,” Nat Geo’s Maya Wei-Haas reports.

Exploring COVID-19: Is there a common gene in various bat species that is involved in the immune system’s response to infection? Are there physical factors, such as smell, that might influence the immune system’s response to a virus like COVID-19? A forensic anthropologist and a conservation biologist, egged on by their frisky African gray parrot, are at the center of both investigations, Eleanor Cummins reports.

Instagram photo of the day

Trees from the time of Charlemagne: Conservationist Bob Claus stands among some of the largest remaining trees in the Tongass National Forest on Prince of Wales Island in Alaska. The trees in this part of the forest have the southernmost exposure in the Tongass, thereby getting a longer growing season. This, in addition to the rich soils provided by the river, has allowed robust growth for these 1,200- to 1,500-year-old spruces and cedars. This particular patch is protected by Congress, but the rest of this national forest remains in peril as a result of the outgoing U.S. administration's efforts to open up to half of the forest to logging.

Related: Rules rollback puts half of Alaskan national forest at risk

The night skies

Best meteor shower of the year? Late Sunday, look toward the northeast for the annual Geminid meteor shower to kick into high gear. With the moon out of the sky during peak hours, even faint meteors may be visible. The Earth will plow into the thickest part of a cloud of debris left by an asteroid named Phaethon from late Sunday night into pre-dawn Monday, producing from 60 to 120 shooting stars per hour. That’s a lot of wishes to make! If you’re up at dawn Saturday, you’ll see the crescent moon sliding by super-bright planet Venus. On Monday, a stunning total solar eclipse graces skies along a narrow strip across central Chile and Argentina, while most of South America can see a partial solar eclipse.— Andrew Fazekas

The big takeaway

So little, and so destructive: Do you see how tiny the spiny water flea is? In the photo above, the bitty flea is is perched on the index finger of a researcher. Despite its size, this invasive predator is destroying the very heart of the Great Lakes—the plankton that munch spreading algae and provide food for the freshwater fish. Without the plankton, young yellow perch and walleye grow more slowly—and are more vulnerable to predators. And fish spit out the water flea because its spiky tail gets caught in their throats, Tim Folger writes for Nat Geo.

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The last glimpse

Protecting the oceans: You may have missed this, but last week the leaders of 14 nations agreed to protect 100 percent of their ocean waters from overfishing, plastic pollution, and agricultural runoff by 2025. Combined, their territorial waters are the size of Africa, Nat Geo’s Laura Parker reports. The nations also agreed to set aside 30 percent of their waters as marine protected areas by 2030. (Pictured above, schools of schools of sweetlips swim the Great Barrier Reef off Australia, which is one of the nations committing to protecting its oceans.)

This newsletter has been curated and edited by David Beard, with photo selections by Jen Tse. Kimberly Pecoraro and Gretchen Ortega helped produce this. Have an idea, a link, a dream to set foot on the moon? We’d love to hear from you at david.beard@natgeo.com . Thanks for reading, and have a good week ahead.

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