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      Scientists find a long-sought electric field in Earth’s atmosphere

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      For the first time, scientists have measured a long-sought global electric field in the Earth’s atmosphere. This field, called the ambipolar electric field, was predicted to exist decades ago but never detected, until now.

      “That’s the big whoop,” says atmospheric scientist Glyn Collinson of NASA’s Goddard Space Flight Center in Greenbelt, Md. “It’s a whole frickin’ new planetary energy field that’s never been measured before!”

      The field is weak, only 0.55 volts — about as strong as a watch battery, Collinson says. But that’s strong enough to control the shape and evolution of the upper atmosphere, features that could have implications for the suitability of our planet for life. More

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      The Webb telescope’s peek into a stellar nursery finds baby planets too

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      A distant stellar nursery holds a clutch of newborn Jupiter-sized worlds, the tiniest of which is surrounded by a dusty disk that might someday give rise to moons. The detailed discovery, made thanks to the unparalleled sensitivity of the James Webb Space Telescope, could provide new insights into star and planetary formation, researchers report in a study in press at The Astronomical Journal.

      Stars arise from enormous clouds of gas and dust when pockets of material collapse under the influence of gravity. The same process can also create smaller nonstellar objects, such as giant planets and brown dwarfs, which lack the internal pressure to fuse hydrogen into helium in their bellies (SN: 7/24/17).

      In the young star cluster NGC1333, located about 1,000 light-years from Earth in the constellation Perseus, a team of astronomers found hundreds of newly formed starlike objects, including six infant worlds with masses between five and 15 times that of Jupiter. The dusty disk around the smallest world is exactly like the kind that circle baby stars and give rise to planetary systems. This dusty disk might one day turn into a pack of orbiting moons, says Adam Langeveld, an astrophysicist at Johns Hopkins University.

      During a recent survey, the James Webb Space Telescope spotted six newborn Jupiter-size worlds, three of which are circled in this annotated composite image of NGC1333. The findings provide insight into the formation of both stars and planets in such regions.ESA, Webb, NASA & CSA, A. Scholz, K. Muzic, A. Langeveld, R. Jayawardhana

      With nothing smaller spotted, it’s possible that he and his colleagues have found the lightest such object that can form with a disk, at least in this particular cluster. And given the parallels between how stars and planets can form, “we’re really probing the limit of the star formation process,” he says.

      Future work will use JWST to look at the chemical composition of the newborn worlds and the surrounding material, potentially helping to explain what kinds of objects can form under what circumstances in this environment. More

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      The historic ‘Wow!’ signal may finally have a source. Sorry, it’s not aliens

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      One of the most compelling potential signs of extraterrestrial communication might have an astrophysical explanation.

      Called the “Wow!” signal, the bright burst of radio waves has defied our understanding since its discovery in the 1970s. Now, scientists using archived data from the Arecibo Observatory in Puerto Rico suggest a new possible source for the signal: a cosmic hydrogen cloud that emitted light like a laser.

      “I think we have probably the best explanation so far,” says astrobiologist Abel Méndez of the University of Puerto Rico at Arecibo. Méndez, together with astrophysicist Kevin Ortiz Ceballos of the Harvard and Smithsonian Center for Astrophysics in Cambridge, Mass., and Jorge Zuluaga of the University of Antioquia, Colombia, submitted this idea to arXiv.org on August 16. More

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      The nearest midsized black hole might instead be a horde of lightweights

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      Contrary to a previous report, there’s no evidence of an intermediate-mass black hole in Omega Centauri, the Milky Way’s most massive and luminous globular star cluster, a new study finds. Instead, a hive of much smaller black holes diving into and out of the tightly packed star cluster’s center can explain the movement and distribution of its many ancient stars.

      “What we found in our analysis is that the data favor an extended component [of stellar-mass black holes] as opposed to an intermediate-mass black hole,” says Andrés Bañares-Hernández, an astronomer at the Instituto de Astrofísica de Canarias in La Laguna, Spain. Some 10,000 to 20,000 stellar-mass black holes — adding up to between 200,000 and 300,000 times the mass of the sun — that are spread around the center of the star cluster can explain the observations, he says. More

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      A distant quasar may be zapping all galaxies around itself

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      One of the farthest known quasars seems to have shut down the creation of new stars in all the galaxies within its vicinity.

      A quasar is a powerful source of light, created by torrid gas orbiting a gargantuan black hole at the center of a galaxy. The intense radiation from one quasar, named VIK J2348-3054, has probably stopped star formation at least 16 million light-years away from itself, astronomer Trystan Lambert and colleagues report in a paper to appear in Astronomy and Astrophysics. More

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      Some meteors leave trails lasting up to an hour. Now we may know why

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      To leave a lasting trail, meteors need to aim low. A new survey of shooting stars shows that meteors that blaze through 90 kilometers up in the sky leave a persistent afterglow, unlike those that burn up at greater heights.

      Meteors are normally blink-and-you’ll-miss-it events. A particle of space dust leaves a fiery trail of light as it zips through the atmosphere, and then it’s gone. But sometimes, a meteor leaves a lingering afterglow. Astronomers have noted these persistent trains for more than a century, but questions remained about their origins. More

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      NASA’s Perseverance rover finds its first possible hint of ancient life on Mars

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      NASA’s Perseverance rover has bagged its first hint of ancient microbes on Mars.

      “We’re not able to say that this is a sign of life,” says Perseverance deputy project scientist Katie Stack Morgan of NASA’s Jet Propulsion Lab in Pasadena, Calif.  “But this is the most compelling sample we’ve found yet.”

      The rover drilled up the sample on July 21 from a reddish rock, dubbed Cheyava Falls after a feature at the Grand Canyon. It is the first piece of Mars that Perseverance has examined that contains organic molecules, the building blocks of life, project scientist Ken Farley of Caltech reported July 25 at the 10th International Conference on Mars in Pasadena. More

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      The North Star is much heavier than previously thought

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      The star marking true north is a good deal heavier than we thought.

      The North Star is 5.1 times as massive as the sun, astronomers report in work submitted July 12 to arXiv.org. That value, calculated from the motion of a much fainter star that orbits the luminary, is nearly 50 percent heavier than a recent estimate of 3.45 solar masses.

      Mass profoundly affects stellar life: The more mass a star has, the faster it burns its fuel and the sooner it dies. The earlier mass estimate had suggested that the North Star, also known as Polaris, is roughly 100 million years old (SN/12/2/16). The new estimate means the star formed more recently than this, but no one has yet calculated a revised age. More