Astro Blog

By Daniel Clery , Science.  Excerpt: Astronomers have discovered more than 6000 planets orbiting other stars—many of them small and rocky like Earth. But despite years of searching, firm evidence that such worlds have stable atmospheres has remained elusive. Now, researchers report in Science that the relatively nearby super-Earth LHS 1140b appears to be leaking helium gas into space , implying it still has a substantial atmosphere billions of years after its birth. ...Many teams are zooming in on LHS 1140b, because of its many charms. Besides being nearby, it could be hiding other gases in its lower atmosphere, such as nitrogen and carbon dioxide—much like Earth. And if those gases provide an element of greenhouse warming, it could possess a liquid water ocean warm enough to swim in....  Full article at https://www.science.org/content/article/astronomers-spot-first-atmosphere-around-potentially-habitable-alien-world .  See also New York Times article, Astronomers Find a...

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 . 

By JONATHAN O’CALLAGHAN , Science.  Excerpt: With surface temperatures hot enough to melt lead, Venus today is a veritable hellhole, despite being similar in size to Earth and orbiting in the habitable zone of the Sun. Yet studies suggest the planet may have once hosted oceans and even conditions suitable for life. Explaining how all that water disappeared has been a problem. A study  published today  in Nature offers a solution, identifying a new water-loss mechanism operating high in Venus’s atmosphere that could have doubled the rate of water loss. Speedier drying could have allowed oceans to exist until later in Venus’s history—implying the planet might have been habitable for longer. ...At 96% carbon dioxide, its atmosphere traps so much heat that surface temperatures reach more than 450°C. Yet spacecraft and telescopes have seen faint hints of water vapor in the atmosphere, and in the late 1970s, NASA’s Pioneer Venus orbiter detected a sign of long-vanishe...

https://skyandtelescope.org/astronomy-news/four-of-uranuss-moons-might-contain-briny-oceans/ By Emily Lakdawala, Sky & Telescope.  Excerpt: A  new paper re-analyzing Voyager observations  suggests that four of Uranus’ five icy satellites also host oceans: Ariel, Umbriel, Titania, and Oberon. (Only small Miranda, intermediate in size between Saturn’s Mimas and Enceladus, appears not to.) The oceans are desperately thin: less than 30 kilometers (20 miles) thick inside Ariel and Umbriel (both of which are about 1,000 kilometers across, similar in size to Saturn’s Tethys and Dione), and less than 50 kilometers thick within Titania and Oberon (which are larger at about 1,500 kilometers, similar to Saturn’s Rhea and Iapetus). If the oceans exist, they would be left over from much larger liquid layers that formed when the moons first formed. ...They’d be extremely briny, hyper-concentrated with whatever dissolved materials helped to lower the temperature at which water would...

https://eos.org/articles/exoplanets-may-support-life-in-the-terminator-zone By lakananda Dasgupta , Eos/AGU.  Excerpt: A new study finds that the intersection between a searing dayside and a freezing nightside could be habitable. The results were presented at  AGU’s Fall Meeting 2022  and were  published recently  in  The Astrophysical Journal . The finding could widen the search for habitable planets in the universe....

https://eos.org/features/marine-science-goes-to-space By Damond Benningfield , Eos/AGU.  Excerpt: Cassini  discoveries added  Enceladus to a growing list of possible ocean worlds in our own solar system—bodies with large amounts of liquid water hidden from view. Some of them could contain more water than all of Earth’s oceans combined. And in addition to Enceladus, planetary scientists have counted at least one other member of the list, Jupiter’s moon  Europa , among the ranks of the “possibly habitable.” “There could be life in our own solar system, and we may already have flown past it,” said  Christopher German , a senior scientist at  Woods Hole Oceanographic Institution and a coleader of  Network for Ocean Worlds  (NOW), a NASA-funded effort to advance research on these intriguing bodies. “Instead of just a sci-fi thing, suddenly we have grounds for wondering if there’s life on these nearby worlds—places we have the technology to reach.” ......

https://www.bbc.com/news/science-environment-49648746 Source:   By Pallab Ghosh, BBC News. Excerpt: Astronomers have for the first time discovered water in the atmosphere of a planet orbiting within the habitable zone of a distant star. The finding makes the world - which is called K2-18b - a plausible candidate in the search for alien life. ...Details were published in the scientific journal Nature Astronomy [ https://www.nature.com/articles/s41550-019-0878-9 ]. ...K2-18b is 111 light-years - about 650 million million miles - from Earth, too far to send a probe. ...The team behind the discovery looked through the planets discovered by the Hubble Space Telescope between 2016 and 2017. The researchers determined some of the chemicals in their atmosphere by studying the changes to the starlight as the planets orbited their suns. The light filtered through the planets' atmospheres was subtly altered by the composition of the atmosphere.Only K2-18b revealed  the molecular sign...

https://www.nytimes.com/2019/07/29/science/nasa-tess-exoplanets-astronomy.html See also Newly discovered exoplanet trio could unravel the mysteries of super-Earth formation in Science Magazine . [ https://www.sciencemag.org/news/2019/07/newly-discovered-exoplanet-trio-could-unravel-mysteries-super-earth-formation ] Source:   By Dennis Overbye, New York Times. Excerpt: NASA’s new planet-hunting spacecraft, the Transiting Exoplanet Survey Satellite, is now halfway through its first tour of the nearby universe. It has been looking for worlds that might be fit for you, me or some other form of life, and as usual, nature has been generous in its rewards. Since its launch in April 2018, TESS has already discovered 21 new planets and 850 more potential worlds that have yet to be confirmed, all residing within a few dozen light years of the sun and our own solar system, according to George Ricker, an M.I.T. researcher who heads the TESS project. So far, he said, TESS “has far exceeded...

Source:   By JoAnna Wendel, Earth & Space Science News (AGU) Excerpt:  Scientists find evidence that a 50-meter-deep pit on the Moon's surface could be a skylight opening to an intact lava tube tens of kilometers long. Lunar colonization isn’t mere science fiction anymore. Billionaires plan to send tourists on once-in-a-lifetime trips, and politicians say that they hope to colonize the Moon in the next few decades. There may even be ways for human colonists to harvest water from ice that may be permanently shadowed in certain caves. But where could a human colony actually live? The Moon has no atmosphere or magnetic field to shield it from solar radiation and micrometeorites that constantly rain onto its surface. That’s no environment for our squishy, earthling bodies. Scientists studying the Moon’s surface may have found the answer: shelter humans in lunar lava tubes. The Moon is covered in huge swaths of ancient basaltic lava flows. Earth’s volcanoes can also erupt s...

Source:  By Shannon Hall, Earth & Space News (EOS; AGU) Excerpt: ...A new hypothesis might reconcile two opposing theories that have tried to explain Mars's mysterious history... suggests that lush periods just long enough to form water-created surface features, such as canyons, punctuated much longer, planet-wide frozen spells. ...In the 1970s, images of Mars taken by the Mariner and Viking spacecraft revealed enormous channels and valley networks—both of which are reminiscent of catastrophic floods and river drainage systems on Earth. The fluvial features were the first sign that 3.8 billion years ago, the planet was once a lush oasis, awash with oceans, lakes, and rivers. ...a 40-year-long debate that has divided planetary astronomers into two camps: those that think Mars must have once contained a thicker and warmer atmosphere—which made the Red Planet hospitable to liquid water and potentially the evolution of life—and those that think Mars was mostly cold save for sho...

Source:   By Shannon Hall, Scientific American Excerpt: Venus is—without a doubt—Earth’s toxic sibling. Although both worlds are similar in size and density, our planetary neighbor has temperatures so high they can melt lead, winds that whip around it some 60 times faster than the planet itself rotates and an atmosphere that slams down with more than 90 times the pressure found on Earth’s atmosphere. But there have been a few tantalizing hints that billions of years ago Venus might have been more akin to Earth’s twin. ...But a few billion years ago a slightly fainter sun might have allowed for a relatively cool Venus, one where liquid water could have pooled in vast oceans that were friendly to life. A new study recently accepted in Geophysical Research Letters suggests that not only was Venus habitable in the distant past, it could have remained habitable for billions of years. Michael Way from NASA’s Goddard Institute for Space Studies and his colleagues applied the fir...

Source:   NASA RELEASE 16-076 Excerpt: Using NASA’s Hubble Space Telescope, astronomers have conducted the first search for atmospheres around temperate, Earth-sized planets beyond our solar system and found indications that increase the chances of habitability on two exoplanets. ...the exoplanets TRAPPIST-1b and TRAPPIST-1c, approximately 40 light-years away, are unlikely to have puffy, hydrogen-dominated atmospheres usually found on gaseous worlds. ...The planets orbit a red dwarf star at least 500 million years old, in the constellation of Aquarius. They were discovered in late 2015 through a series of observations by the TRAnsiting Planets and PlanetesImals Small Telescope (TRAPPIST), a Belgian robotic telescope located at ESA’s (European Space Agency’s) La Silla Observatory in Chile. TRAPPIST-1b completes a circuit around its red dwarf star in 1.5 days and TRAPPIST-1c in 2.4 days. The planets are between 20 and 100 times closer to their star than the Earth is to the sun. B...

Source:   By Glen Roberts Jr., Berkeley Lab News Center. Excerpt: WFIRST will explore mysteries of dark energy, hunt for distant planets, retrace universe's history during 6-year mission. ...The Wide Field Infrared Survey Telescope (WFIRST) will launch into its six-year mission from Cape Canaveral, Fla., in the mid-2020s. ...The telescope will be NASA’s next major astrophysics observatory following the launch of the James Webb Space Telescope in 2018. ...WFIRST is a 2.4-meter telescope with a primary mirror the same size as that of the Hubble Space Telescope. It has a field of view that is 100 times larger than Hubble’s infrared instrument and will measure light from an estimated billion galaxies. WFIRST is a 2.4-meter telescope with a primary mirror the same size as that of the Hubble Space Telescope. It has a field of view that is 100 times larger than Hubble’s infrared instrument and will measure light from an estimated billion galaxies.... http://newscenter.lbl.gov/2016/0...

Source:   NASA    Press release 13-073 Excerpt: An analysis of a rock sample collected by NASA's Curiosity rover shows ancient Mars could have supported living microbes. Scientists identified sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon -- some of the key chemical ingredients for life -- in the powder Curiosity drilled out of a sedimentary rock near an ancient stream bed in Gale Crater on the Red Planet last month. "A fundamental question for this mission is whether Mars could have supported a habitable environment," said Michael Meyer, lead scientist for NASA's Mars Exploration Program at the agency's headquarters in Washington. "From what we know now, the answer is yes." http://www.nasa.gov/home/hqnews/2013/mar/HQ_13-073_Curiosity_Rock_Analysis.html

Source:   Dan Vergano, USA TODAY Excerpt: …some solace comes from the Kepler space telescope team's estimate that just in our Milky Way galaxy alone, some 500 million planets likely orbit inside their star's habitable zone. "We have many candidates in that region," said Kepler principal scientist William Borucki of NASA's Ames Research Center in Moffett Field, Calif., at a briefing unveiling Kepler-22b to his colleagues earlier this month. At his briefing, Borucki showed a chart depicting more than 50 possible habitable zone planets, … www.usatoday.com/tech/science/columnist/vergano/story/2011-12-18/kepler-habitable-planets/52031444/1

Source:   John Spencer, Physics Today Excerpt: [page 38] ....Has life developed in the warm, wet conditions that we suspect exist within Enceladus? A positive answer would have profound implications for the ubiquity of life throughout the cosmos and its ability to develop independently of solar or stellar energy input. Even if the answer is negative, an understanding of how close Enceladus has come to being able to support life would tell us much about the potential development of habitable environments elsewhere in the solar system and beyond. physicstoday.org/resource/1/phtoad/v64/i11/p38_s1

Source:   Tim Folger, Discover Magazine Excerpt:  The Kepler space telescope, NASA’s first mission dedicated to the search for planets beyond our solar system, has produced a gusher of strange new worlds. If astronomers are right, many of them will prove to be habitable. …Kepler-10 b …announced … this past January, was the smallest world yet found beyond our solar system. …Kepler-10 b was merely a preview. A month after the January announcement, NASA released its first full data set from the Kepler mission, and the results left astronomers straining for superlatives. ...“We’re learning about a diversity of worlds in our universe that we had no clue about beforehand,” Marcy says. “Rocky planets, yeah, we thought there might be some of those. By the way, we’re finding some rocky planets that are even denser than Earth. But we’re also finding these mini-Neptunes, a class of planet for which we have no examples in our solar system. They’re like small Neptunes but with huge ...

Source:   Fox News Online Excerpt: If ET phones, we're listening again — thanks to you.  Astronomers at the cash-strapped SETI Institute are poised to resume the quest for extraterrestrial life, after raising more than $200,000 to restart a key array of telescopes…. www.foxnews.com/scitech/2011/08/08/with-new-funding-quest-for-alien-life-is-back-on/

Source:   Kirsty Lang, BBC News  Excerpt: …A red dwarf star 20 light-years away is again providing hints that it hosts the first definitively habitable planet outside our Solar System. The planet Gliese 581d is at the colder outer edge of the "Goldilocks zone" in which liquid water can be sustained. Now a study in Astrophysical Journal Letters suggests its atmosphere may keep things warm enough for water. www.bbc.co.uk/news/science-environment-13423085

Source:   UPI Excerpt: Berkeley, Calif. — U.S. astronomers [at the University of California] searching for alien life say they'll aim radio telescopes at some likely candidates among 1,235 planets discovered by a NASA space telescope…. once they acquire 24 hours of data on a total of 86 Earth-like planets among those found by the Kepler space telescope, they'll initiate a coarse analysis and then, in about two months, ask an estimated 1 million SETI@home users to conduct a more detailed analysis on their home computers, a [UC] Berkeley release reported last week…."We've picked out the planets with nice temperatures -- between zero and 100 degrees Celsius (32 degrees to 212 degrees F.) -- because they are a lot more likely to harbor life," said physicist Dan Werthimer, Chief Scientists for SETI@HOME. See also article in  Popular Science  and NPR's and  All Things Considered www.upi.com/Science_News/2011/05/16/SETI-search-to-look-at-likely-worlds/UPI-9...