Astro Blog

Source:   By Dennis Overbye, The New York Times Excerpt: A prime planet listing has just appeared on the cosmic real estate market, possibly the most promising place yet to search for signs of life beyond the solar system, the astronomers who discovered it say. It is a rocky orb about one and a half times the size of Earth, about 40 light years from here. It circles a dwarf star known as LHS 1140 every 25 days, an orbit that puts it in the “Goldilocks” zone where temperatures are conducive to liquid water and perhaps life as we know it. It is close enough that astronomers are hopeful that with the next generation of big telescopes, they will be able to probe its atmosphere for signs of water or other evidence of suitability for life. “This planet is really close to us: If we shrank the Milky Way to the size of the United States, LHS 1140 and the sun would fit inside Central Park,” David Charbonneau, of the Harvard-Smithsonian Center for Astrophysics, said in an email. His colle...

Source:   By Paul Voosen, Science 2017-04-13. . . For GSS A Changing Cosmos chapter 7. Excerpt: In 2005, NASA’s Cassini spacecraft spied jets of water ice and vapor erupting into space from fissures on Enceladus, evidence of a salty ocean beneath the saturnian moon’s placid icy surface. Now, it turns out that the jets contain hydrogen gas, a sign of ongoing reactions on the floor of that alien sea. Because such chemistry provides energy for microbial life on Earth, the discovery makes Enceladus the top candidate for hosting life elsewhere in the solar system—besting even Jupiter’s Europa, another icy moon with an ocean. “We didn’t see microbes,” says Hunter Waite, a planetary scientist at the Southwest Research Institute in San Antonio, Texas, and the lead author of a study published this week in Science. “But we saw their food.”... http://www.sciencemag.org/news/2017/04/food-microbes-abundant-enceladus

Source:   By Jet Propulsion Laboratory News Excerpt:  A relatively large near-Earth asteroid discovered nearly three years ago will fly safely past Earth on April 19 at a distance of about 1.1 million miles (1.8 million kilometers), or about 4.6 times the distance from Earth to the moon. Although there is no possibility for the asteroid to collide with our planet, this will be a very close approach for an asteroid of this size. The asteroid, known as 2014 JO25, was discovered in May 2014 by astronomers at the Catalina Sky Survey near Tucson, Arizona -- a project of NASA's NEO Observations Program in collaboration with the University of Arizona. (An NEO is a near-Earth object). Contemporary measurements by NASA's NEOWISE mission indicate that the asteroid is roughly 2,000 feet (650 meters) in size, and that its surface is about twice as reflective as that of the moon. ...Small asteroids pass within this distance of Earth several times each week, but this upcoming close appr...

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 JoAnna Wendel, Earth & Space Science News, EoS (AGU) Excerpt: It’s a flying saucer! No, a celestial empanada! Or space ravioli? Nope—the weird raw images dropped by NASA’s Jet Propulsion Laboratory this week feature Saturn’s tiny moon Pan and its equatorial fringe in unprecedented detail. The Cassini spacecraft, which has been orbiting Saturn since 2004, will crash into Saturn later this year. But its final descent brings the spacecraft closer than ever before to Saturn’s rings and offers scientists a wealth of new research opportunities.This is because the spacecraft has entered its “ring grazing orbits,” Carolyn Porco, leader of the imaging science team for Cassini and current visiting scholar at the University of California in Berkeley, told Eos. ...This close orbit allows the spacecraft to take close-up pictures of moons like Pan, which orbits Saturn at a distance of 134,000 kilometers. The new images of the 35-kilometer-wide moon feature a res...

Source:   NASA RELEASE 17-015 Excerpt:  NASA announced the discovery of the most Earth-sized planets found in the habitable zone of a single star, called TRAPPIST-1. This system of seven rocky worlds–all of them with the potential for water on their surface–is an exciting discovery in the search for life on other worlds. There is the possibility that future study of this unique planetary system could reveal conditions suitable for life....   See also NASA full press conference on discovery of 7 Earth-like exoplanets  (37 min), TRAPPIST-1e Travel Poster , NY Times article - 7 Earth-Size Planets Orbit Dwarf Star, NASA and European Astronomers Say (includes video clip), JPL video - NASA & TRAPPIST-1: A Treasure Trove of Planets Found . https://www.nasa.gov/press-release/nasa-telescope-reveals-largest-batch-of-earth-size-habitable-zone-planets-around

Source:   By CBC News, Thomson Reuters Excerpt: A NASA spacecraft has detected carbon-based materials, similar to what may have been the building blocks for life on Earth, on the Texas-sized dwarf planet Ceres that orbits between Mars and Jupiter in the main asteroid belt, scientists said on Thursday. The finding puts Ceres, a rock-and-ice world about 950 kilometres in diameter, on a growing list of places in the solar system of interest to scientists looking for life beyond Earth. The list includes Mars and several ocean-bearing moons of Jupiter and Saturn. The discovery, published in the journal Science, was made by a team of researchers using NASA's Dawn spacecraft, which has been orbiting Ceres for nearly two years. "I think these organic molecules are a long way from microbial life," Dawn lead scientist Christopher Russell of the University of California Los Angeles (UCLA) wrote in an email to Reuters. "However, this discovery tells us that we n...