How did coronavirus spread so far, so fast?

This is part of our daily newsletter series. Want this in your inbox? Subscribe here.

By Victoria Jaggard, SCIENCE Executive Editor

One thing we know about this mysterious pneumonia-like illness dominating world headlines: It moves fast. Starting in a food market in central China, the new strain of coronavirus moved to the nation's major cities, jumped borders to neighboring countries, and has now shown up on the West Coast of the United States.

All in three weeks.

The spread has health officials worried about the world’s biggest annual migration of humans, the millions of people who normally travel across China to celebrate Lunar New Year. The situation has also been complicated by a lack of information from Chinese authorities, the Washington Post reports. World health officials are meeting today to determine whether this is an outbreak, and they need to know whether all these cases popping up are tied to the same city, Wuhan.

To trace the virus’s speedy path, health officials are looking for clues in outbreaks of the past, such as SARS and MERS. One worrying theme: These lethal respiratory diseases all started in wildlife markets. “In Wuhan’s case, the closest match is other SARS-related coronaviruses that are found in bats,” EcoHealth Alliance’s Kevin Olival tells Nat Geo’s Nsikan Akpan. “Cutting back the wildlife trade has a win-win effect of both protecting species that are harvested from the wild and of reducing spillover of new viruses.

Do you get this daily? If not, sign up here or forward to a friend.

Today in a minute

Illegal constellation? The FCC may have violated U.S. law in approving SpaceX’s Starlink constellation of satellites, which astronomers are saying have blocked our observations of the night skies. That’s according to an upcoming paper detailed in Scientific American. The paper authors argue that the FCC should have considered the environmental impact these satellites would have on the natural sky, and that not doing so opens the agency up to a lawsuit.

Greta Thunberg at Davos: The young climate activist’s latest message to the world’s powerful boils down to this: Why should our planet’s emerging generations trust you when you've proven you do not have our interests in mind? "You say children shouldn’t worry," Thunberg told the World Economic Forum on Tuesday. "You say: Just leave this to us. We will fix this, we promise we won’t let you down. And then, nothing. Silence. Or something worse than silence. Empty words and promises."

Revealing a black hole: First came the first photo of a black hole last year, a billion light-years away. Now, charting how x-rays behave near a different, more distant black hole, scientists have created the most detailed map yet of the region around the behemoth’s event horizon, Nat Geo's Nadia Drake reports. “Black holes don’t give off any light themselves, so the only way we can study this is by watching what matter does as it falls onto it,” says the University of Cambridge’s William Alston.

Silver lining: There’s a brighter view of the asteroid collision 66 million years ago that killed three-quarters of the species on Earth. The collision, and a massive marine die-off, tempered subsequent global warming for the next 300,000 years amid epic volcanic eruptions that happened before and after the impact, Tim Vernimmen reports for Nat Geo.

Your Instagram photo of the day

View Images

The glow at night: A glow from the world's largest lava lake mixes with moonlit clouds above the caldera of Mount Nyiragongo, an active stratovolcano in the Democratic Republic of the Congo. Located inside Virunga National Park, Nyiragongo and nearby Nyamuragira are together responsible for 40 percent of Africa’s historical volcanic eruptions. Since 1882, Nyiragongo has erupted at least 34 times. The last eruption, in 2002, destroyed 15 percent of the nearby city of Goma, killed 147 people, and left 120,000 people homeless.

Are you one of our 130 million Instagram followers? (If not, follow us now.)

This week in the night sky

View Images

Moon meets Mercury, Venus: As soon as the sun sets on Saturday, use binoculars to scan the southwestern horizon for a whisker-thin crescent moon very close to Mercury. The faint, star-like planet will be separated from the moon by only two degrees—equal to the width of your two fingers held at arm’s length. The trick to catching this special pairing is to find a spot that has a clear line of sight right down to the horizon—and wait for the sun to completely set before scanning the sky. Then, at dusk on Monday and Tuesday, look for the crescent moon to make an eye-catching pairing with the superbright planet Venus.—Andrew Fazekas

The big takeaway

View Images

Overdue: When pioneering dark-matter expert Vera C. Rubin, shown here in 1965, gained access to the 200-inch Palomar Observatory in California, she found there was no women’s restroom. So she taped an image of a skirt over the “man” on the door of the men’s room, and voila! Problem solved. Now there will be an entire Vera C. Rubin Observatory, the National Science Foundation announced earlier this month. It is being built in Cerro Pachon, in Chile, to try to capture evidence of the dark matter in our universe. Rubin, who died in 2016, would probably have loved the facility, which will be completed in 2022. “It’s heartening and highly appropriate to see Vera Rubin honored in this way,” University of California, Santa Cruz, astronomer Natalie Batalha told the New York Times.

Read: Vera Rubin’s motto: ‘Science progresses best when observations force us to alter our preconceptions.'

Did a friend forward this to you?

Come back tomorrow for Rachael Bale on the latest in animal news. If you’re not a subscriber, sign up here to also get Whitney Johnson on photography, Debra Adams Simmons on history, and George Stone on travel.

The last glimpse

View Images

Strange magic: Photographing at night, Reuben Wu uses distinctive lighting to find new ways to look at nature. Above, with a drone and LED lighting, he captures California’s Crowley Lake, and its reflection. Wu says he’s driven “not just by the urge to create imagery, but by a desire to explore new places as if they were unknown territory.” He sees the night as a blank canvas, and his controlled use of light on landscapes is akin to that of a portrait artist with a human subject.

Read: How this photographer captures landscapes at night

This newsletter has been curated and edited by David Beard, with photo selections by Eslah Attar. Have an idea or a link? We'd love to hear from you at Thanks for reading!