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Why are Tatooine planets rare? Blame general relativity

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By Robert Sanders , UC Berkeley News.  Excerpt: Of the more than 4,500 stars known to have planets, one puzzling statistic stands out. Even though nearly all stars are expected to have planets and most stars form in pairs, planets that orbit both stars in a pair are rare. Of the more than 6,000 extrasolar planets, or exoplanets, confirmed to date — most of them found by NASA’s Kepler Space Telescope and the Transiting Exoplanet Survey Satellite (TESS) — only 14 are observed to orbit binary stars. There should be hundreds. Where are all the planets with two suns, like Tatooine in  Star Wars ? Astrophysicists at the University of California, Berkeley, and the American University of Beirut have now proposed a reason for this dearth of circumbinary exoplanets — and Einstein’s general theory of relativity is to blame. ...If a planet is orbiting the pair of stars, the gravitational tugs from the stars make the planet’s orbit precess, ...similar to the way the axis of a spinning top...
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Earth-size planet spotted with yearlong orbit

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By Elise Cutts , Science.  Excerpt: Astronomers are planning ambitious telescopes to search for signs of life on distant planets. A newly discovered world, announced here last week at the Rocky Worlds conference and  published yesterday  in  The Astrophysical Journal Letters , might just be the perfect target. The planet, called HD 137010 b, is almost exactly Earth-size. At 355 days, its orbit is almost exactly Earth-like, too. And its star is bright and just 146 light-years away–close enough to be observed in detail with future telescopes....  Full article at https://www.science.org/content/article/earth-size-planet-spotted-yearlong-orbit . 
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JWST spots most distant galaxy ever, pushing the limits of the observable universe

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By Jackie Flynn Mogensen , Scientific American.  Excerpt: The galaxy MoM-z14 could offer clues to what the universe looked like in its early infancy. ...On Wednesday astronomers on  announced that a bright galaxy  called MoM-z14 that was found using NASA’s  James Webb Space Telescope  (JWST) is the farthest yet detected, existing just 280 million years after the big bang. ...The galaxy, the light of which has taken more than 13 billion years to reach our telescopes, is  brighter, denser and more chemically rich than astronomers had expected , according to NASA....  Full article at https://www.scientificamerican.com/article/jwst-spots-most-distant-galaxy-ever-pushing-the-limits-of-the-observable/ . 
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Tidal waves of lava may slosh around alien worlds

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By Elise Cutts , Science.  Excerpt: Towering tidal waves of lava could be rolling around hot alien worlds, researchers reported last week, here at the  Rocky Worlds conference  and in a  preprint  posted on arXiv this month. The Sun and Moon drive tides on Earth, but these tidal waves would be tugged up by the intense gravitational forces endured by planets in tight orbits around their stars. For instance, lava tidal waves on the blazing-hot exoplanet 55 Cancri e—a rocky world that orbits its star every 18 hours—could rise several hundred meters high and surge at the speed of a human sprinter, says Mohammad Farhat, a planetary scientist at the University of California (UC), Berkeley who presented the modeling study. ...Scientists often look for alien air by taking the temperatures of planets’ dayside hemispheres. The presence of an atmosphere would spread heat around to the nightside, making the dayside look cooler than expected for a bare rock. But if lava wave...
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This ‘Galaxy That Wasn’t’ Never Bore Any Stars

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By Katrina Miller , The New York Times.  Excerpt: This week, astronomers announced the discovery of a new kind of cosmic object, something that is very nearly a galaxy, save for one crucial, missing ingredient: stars. The almost-galaxy is about 14 million light-years from Earth. It was the ninth cloud found to be associated with a nearby spiral galaxy, leading to its serendipitous name: Cloud-9. The object is starless, consisting of only a haze of hydrogen gas that astronomers believe is swaddled in a much more massive clump of  dark matter,  the invisible substance that permeates the cosmos and shapes its overarching structure. ...Cloud-9 is the first confirmed example of what astronomers call a RELHIC, short for Reionization-Limited H I Cloud and pronounced “relic.” Such objects are rich in gaseous hydrogen but devoid of any stars. They are  failed galaxies  thought to be nearly as old as time itself, primordial fossils that can help astronomers understand the...
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NASA’s Mars Sample Return mission is dead

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By Paul Voosen , Science.  Excerpt: After years on life support, NASA’s plan to collect martian rocks and ferry them back to Earth has died. Yesterday, Congress  released  a  compromise spending bill  for the present financial year that backs the White House’s effort to kill the Mars Sample Return (MSR) program. Although the bill must be passed by both congressional chambers and signed into law, it effectively signals the end of MSR....  Full article at https://www.science.org/content/article/nasa-s-mars-sample-return-mission-dead . 
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Titan might not have an ocean after all

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By Hannah Richter , Science.  Excerpt: In the late 2000s, planetary scientists scoured data gathered by NASA’s Cassini mission, a Saturn orbiter, about the planet’s mysterious icy moon Titan. Their exciting conclusion: The frozen world harbored an ocean sloshing around tens of kilometers beneath a thick ice shell. The ocean, hundreds of kilometers deep itself, might even be a cauldron for the “prebiotic” organic chemistry that led to life on Earth, they proposed. Now, nearly 2 decades later, researchers think they may have gotten the story all wrong. Research  presented today  here at the American Geophysical Union’s annual meeting and  published in  Nature  claims that although Titan may have once harbored a liquid ocean, today it is frozen, except for smaller melted zones deep beneath the surface. If true, the discovery will upend the long-standing assumption that Saturn’s biggest moon is a water world, like other moons in the outer Solar System,  in...
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