Health & Science

A planet in the ‘Goldilocks zone’

Scientists say they’ve identified the first planet outside our solar system that could support life more or less as we know it. Gliese 581d orbits a red-dwarf star 20 light-years away, which is “very close to Earth, relatively speaking,” researcher Robin Wordsworth tells BBCNews.com. Using new 3-D computer modeling, Wordsworth and colleagues at the Pierre Simon Laplace Institute in Paris say they’ve established that Gliese 581d is orbiting in the “Goldilocks zone” of its star, where temperatures are just right for water to exist as oceans, clouds, and rain. They say their research reverses previous findings that the orb was too cold for that, but they acknowledge that it would “still be a pretty strange place to visit.” Its dense carbon-dioxide atmosphere probably allows only murky red light to reach the surface. The planet is seven times the mass of Earth and exerts twice the gravity; one side always faces its sun, while the other is permanently dark and frozen. Wordsworth says the relative accessibility of the planet is “particularly exciting.” Even though it would take a current-day spaceship 300,000 years to get there, “with future generations of telescopes, we’ll be able to search for life on Gliese 581d directly,” he says.

Winning by a whisker

The Week

Escape your echo chamber. Get the facts behind the news, plus analysis from multiple perspectives.

SUBSCRIBE & SAVE

Sign up for The Week's Free Newsletters

From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.

From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.

Sign up

Harbor seals can hunt successfully in some of the world’s murkiest waters because they use their whiskers to judge the size and shape of potential prey, a new study suggests. Wolf Hanke and his colleagues at the University of Rostock in Germany put blindfolds and noise-canceling headphones on a trained seal named Henry to test the sensitivity of his whiskers. They found that he could tell the difference between two paddles­—one of which was only 1.4 inches larger than the other­—just by sensing their wakes as they were swept through his tank. Henry could also distinguish among various paddle shapes and movements. Scientists knew that seals used their whiskers to track prey, but they were surprised to discover what precise information the whiskers glean from the movement of water. “If the seal can avoid tracking fish that are too small or too big,” Hanke tells The New York Times, “this saves energy”—something seals can’t afford to waste in their harsh, cold environment.

A new form of life?

Strange microscopic organisms found in a British pond may force a fundamental rethink of how we classify living things. Close study of the organisms, called cryptomycota or “hidden fungi,” has led a team of British scientists to believe that they may not be fungi at all, but instead constitute their own unique kingdom alongside plants and animals. Unlike most fungi, cryptomycota have no rigid cell walls to hold themselves together. Although specimens have been found everywhere from ocean sediment to farmland, scientists are still puzzling over how their bodies are structured, what they eat, and how they reproduce. “It is possible there are many different forms of this organism with a range of characteristics we don’t even know about yet,” researcher Meredith Jones of the University of Exeter tells LiveScience.com. She suggests that “they probably play an important role in a range of environmental processes.” DNA analysis shows that cryptomycota are older than any fungus yet uncovered and may be “the missing link,” Jones says, “between fungi and the rest of the kingdom of life.”

Billions of lonely planets

Planets without suns, long considered a rarity, might actually be twice as numerous as stars in the Milky Way. Takahiro Sumi, of Osaka University in Japan, and his colleagues have found evidence that the galaxy contains hundreds of billions of free-floating, Jupiter-size planets, which have previously gone undetected because astronomers were searching only for planets that closely orbit stars. “This is an amazing result,” Yale astronomer Debra Fischer told Nature.com. The astronomers discerned the size and position of the unbound planets by microlensing, or studying how their gravity caused minute but measurable distortions in the light from distant stars as the planets passed before them. It isn’t yet clear whether the planets, known as gas giants, are entirely unmoored from stars or just in extremely distant orbits. But current theories predict that if such relatively large bodies have managed to escape from stellar orbit, it is likely that many more Earth-size planets are wandering the heavens undetected, too. “They might be littering the galaxy,” Fischer says.