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New-found planet at Proxima Centauri
Astronomers have discovered a third planet orbiting Proxima Centauri, the star closest to the Sun. Called Proxima Centauri d, the newly spotted world is probably smaller than Earth, and could have oceans of liquid water. “It’s showing that the nearest star probably has a very rich planetary system,” says astronomer Guillem Anglada-Escudé, who led the team that, in 2016, discovered the first planet orbiting the star.
China approves gene-edited crops
Researchers in China have welcomed the government’s approval of gene-edited crops. China’s new rules are more conservative than those in the United States, which does not regulate plants that incorporate small changes similar to those that could occur naturally. But they are more lenient than the European Union’s tough stance: treating all gene-edited crops the same as genetically modified organisms, whose creation involves the insertion of entire genes or DNA sequences from other plant or animal species. “This is very good news for us. It really opens the door for commercialization,” says plant biologist Caixia Gao, who co-authored a recent Nature paper on genome-edited wheat that is resistant to powdery mildew.
The science of fake snow
Artificial snow, like the stuff being enjoyed by Olympic athletes near Beijing, is very different from the real thing. Pure water doesn’t freeze until it reaches nearly –40 ℃, writes atmospheric scientist Peter Veals. Snow needs to form around a core to freeze at 0 ℃, so most fake snow is seeded with specks of protein produced by the bacteria Pseudomonas syringae. The artificial stuff also forms as tiny spheres of ice, rather than slowly growing onto six-sided snowflakes. Some skiers and snowboarders actually prefer the fast, icy fake stuff — although it can make for a hard, painful fall.
How to tame water on sizzling surfaces
A surface that combines the geometric and thermal properties of different materials can stop water droplets from bouncing and skittering on very hot surfaces. This phenomenon — called the Leidenfrost effect — is something that engineers often want to avoid because it makes water-based cooling systems less efficient. The design combines conductive steel pillars, u-shaped channels and an insulating membrane, and works above 1,000 °C.
Features & opinion
Of hearts, heads and blobs
When it comes to mascots for Valentine’s day, people don’t typically think about sea squirts: blobby, headless creatures that spend their lives stuck to the sea floor. But they are vertebrates’ closest living relatives — and they have a developmental connection similar to the one in vertebrates that links the muscles of the heart with those that make it possible to have important vertebrate-y things such as a head and jaws. Scientists are probing these connections in hopes of better understanding the last common ancestors of sea squirts and other tunicates.
Navigating fertility in academia
Two scientists who faced fertility issues at different ages and career stages share how it affected their research and professional lives. “These lessons might do little to relieve the pain of infertility,” they write, “but we hope that they help people going through these struggles to become more resilient, more adaptable and perhaps even a happier academic.”
Female scientists: don’t wait to be perfect
“I have worked in some of the most male-dominated sectors you can work in,” says Pontsho Maruping, who started her career in mining and is now a deputy managing director at the South African Radio Astronomy Observatory. She offers detailed advice for up-and-coming women in African science and engineering. “When offered a chance to lead a new project, I tell young professionals to say ‘yes’,” she writes. “Women tend to want to be perfect first, but it’s the times when I’ve said yes to challenges that have provided the biggest opportunities to grow career-wise.”
Squaring the circle, right before your eyes
Squaring the circle is a mathematical conundrum so iconic that it has become an idiom for achieving the impossible. Now, mathematicians have found the most efficient way to solve the puzzle. They show that you can make a square with the same area as a given circle (or vice-versa) by slicing it into pieces and then rearranging them. And, as neatly demonstrated in an animation in this Quanta article, the pieces can be made simple enough, and large enough, that they are clear to see.