Eliana Willis

Uranus emits more energy than it gets from the sun, two new studies report — a discovery that contradicts findings from the venerable Voyager spacecraft.

When Voyager 2 sped past Uranus on January 24, 1986, the spacecraft detected no significant excess heat from the planet, making it seemingly unique among the sun’s giant worlds. However, new observations from space- and ground-based telescopes reveal that Uranus does in fact radiate more energy than sunlight provides, two research teams report in work submitted to arXiv.org in late February. More

Jupiter’s moon Io, the most volcanically active body in the solar system, is littered with hundreds of erupting volcanoes. High-resolution images now reveal several dozen lava lakes, researchers report in the February Journal of Geophysical Research: Planets. These lakes are far larger than their analogs on Earth, and their structure sheds light on how magma moves beneath the surface of Io. 

Io’s volcanism — probably present over the moon’s entire 4.6-billion-year existence — was discovered when the Voyager spacecraft flew by in 1979. The volcanic activity is caused by the intense gravitational pulls of Jupiter and nearby moons, which deform Io by tens of meters. “This squeezing is heating the body,” says Alessandro Mura, a planetary scientist at Italy’s National Institute for Astrophysics in Rome. More

BOSTON —Droplets of Venus’ clouds may someday come to Earth. Researchers are testing a device that can gather mist from our planetary neighbor’s atmosphere and deliver it to scientists so they can test the samples for signs of life.

Venus is not an obvious place to look for life. Its globe-spanning cloud decks are made of sulfuric acid, “a feature that was long believed to be sterile for any organic chemistry,” said MIT planetary scientist Iaroslav Iakubivskyi in a Feb. 15 talk at a meeting of the American Association for the Advancement of Science.

But in the last few years, lab experiments by Iakubivskyi and colleagues have suggested that sulfuric acid can support the organic chemistry that gives rise to stable nucleic and amino acids — the building blocks of DNA and proteins. Together, the data suggest that “rather than being a disruptive force, sulfuric acid might actually serve as a potential solvent for life-essential molecules,” he said. “Still, we have to go to Venus to test it.”

A future mission to Venus could include floating a cloud-catching device from a giant balloon in the planet’s sulfuric acid atmosphere, as shown in this illustration.W. Buchanan

Iakubivskyi’s team is working with the private spaceflight company Rocket Lab on a series of Venus probes called the Morning Star Missions. The first, a probe that will fall through Venus’ atmosphere and measure the sizes of sulfuric acid droplets, is slated to launch in 2026. A later mission would use a two-ton rocket to launch samples into Venus’ orbit to be picked up by a spacecraft returning to Earth. If successful, Morning Star would be the first private mission to another planet.

Inspired by fog-catching plants in the Atacama desert, the team built a prototype cloud catcher from four layers of wire mesh. The wires can be charged to ionize atmospheric droplets and attract them to the mesh. More

A giant impact 3.8 billion years ago sent a curtain of rock flying away from a point near the moon’s south pole. When that curtain fell, its rocks plunged up to 3.5 kilometers into the lunar surface with energies 130 times greater than the global inventory of nuclear weapons, new calculations show.

And that’s how a hailstorm of boulders carved out two gargantuan canyons on the moon in less than 10 minutes.

“They landed in a staccato fashion, bang-bang-bang-bang-bang,” says planetary geologist David Kring of the Lunar and Planetary Institute in Houston, who reports the finding February 4 in Nature Communications. More

Pluto and Charon’s meet-cute may have started with a kiss. New computer simulations of the dwarf planet and its largest moon suggest that the pair got together in a “kiss-and-capture” collision, where the two bodies briefly joined up before settling into their current positions.

“It’s a U-Haul situation,” says planetary scientist Adeene Denton of the Southwest Research Institute in Boulder, Colo., who reports the results January 6 in Nature Geoscience. “They kiss and they say, ‘Yeah, this is it. I want to build a system together with you.’ And then they do.” More

WASHINGTON D.C. — The Perseverance Rover on Mars may have stumbled upon the oldest rocks humans have ever seen and, possibly, evidence of a new setting that ancient Martian organisms could have inhabited, if they ever existed.

“This is really one of the most exciting things that this mission is going to do, is to be looking at rocks that were formed so early in the history of the solar system,” said Caltech geochemist Kenneth Farley during a December 12 news briefing at a meeting of the American Geophysical Union. “Almost the dawn of the solar system.” More