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When giant stars eat giant planets, their starlight may shine a bit less brightly. That dimming could affect how astronomers measure distances across the universe — and possibly even put past measurements in doubt. “You would think the planet would be a small perturbation to the star,” says astrophysicist Licia Verde. “It turns out that […] More
Saturn’s auroras may heat its atmosphere like an electric toaster. Measurements from NASA’s Cassini spacecraft’s final orbits show that Saturn’s upper atmosphere is hottest where its auroras shine, a finding that could help solve a long-standing mystery about the outer planets. Saturn’s upper atmosphere is much hotter than scientists first expected based on the planet’s […] More
A suspected subsurface ocean on Pluto might be old and deep. New analyses of images from NASA’s New Horizons spacecraft suggest that the dwarf planet has had an underground ocean since shortly after Pluto formed 4.5 billion years ago, and that the ocean may surround and interact with the rocky core. If so, oceans could […] More
Creeping tendrils of slime seem to mirror the structure of the universe’s enormous filaments. That superficial similarity, in an organism called a slime mold, helped scientists map out the cosmic web, the vast threads of matter that connect galaxies. Made up of gas and the unidentified substance called dark matter, the cosmic web began forming […] More
The asteroid Ryugu is light and fluffy. Images taken by Japan’s Hayabusa2 spacecraft suggest the whole asteroid is highly porous, scientists report in Nature on March 16. “It is something like freeze-dry coffee,” says planetary scientist Tatsuaki Okada of the Japanese Aerospace Exploration Agency. If early protoplanets had similar structures, that could mean planets formed […] More
A joint European and Russian mission to Mars is being postponed from July until sometime in 2022, as the coronavirus pandemic is preventing scientists from resolving a few technical difficulties, the European Space Agency said March 12. “We cannot fly in 2020,” ESA director general Jan Wörner says. “This is a disappointment for me personally, […] More
On one distant world, “heavy metal” could be a weather forecast. Telescope observations indicate that an exoplanet nearly 400 light-years away has iron rain. The planet, dubbed WASP 76b, is an extreme kind of exoplanet known as an ultrahot gas giant (SN: 7/30/19). These worlds “are complete oddballs,” says astronomer David Ehrenreich of the University […] More
Some puzzling planets called superpuffs could be Saturns in disguise. These exoplanets appear very large given their masses, suggesting that they have densities like cotton candy. Astronomers have struggled to explain how these planets could have turned out so fluffy (SN: 11/30/15). “People had been thinking of complicated ways to explain these mysterious planets,” such […] More
