Search the Community
Showing results for tags 'astronomy'.
Found 4 results
-
The Cassini spacecraft has begun returning its best-ever views of the northern extremes of Saturn’s icy ocean-bearing moon. NASA’s Cassini spacecraft has begun returning its best-ever views of the northern extremes of Saturn’s icy ocean-bearing moon Enceladus. The spacecraft obtained the images during its October 14 flyby, passing 1,142 miles (1,839 kilometers) above the moon’s surface. Mission controllers say the spacecraft will continue transmitting images and other data from the encounter for the next several days. Scientists expected the north polar region of Enceladus to be heavily cratered, based on low-resolution images from the Voyager mission, but the new high-resolution Cassini images show a landscape of stark contrasts. “The northern regions are crisscrossed by a spidery network of gossamer-thin cracks that slice through the craters,” said Paul Helfenstein from Cornell University in Ithaca, New York. “These thin cracks are ubiquitous on Enceladus, and now we see that they extend across the northern terrains as well.” Cassini’s next encounter with Enceladus is planned for October 28, when the spacecraft will come within 30 miles (49km) of the moon’s south polar region. During the encounter, Cassini will make its deepest-ever dive through the moon’s plume of icy spray, sampling the chemistry of the extraterrestrial ocean beneath the ice. Mission scientists are hopeful data from that flyby will provide evidence of how much hydrothermal activity is occurring in the moon’s ocean, along with more detailed insights about the ocean’s chemistry, both of which relate to the potential habitability of Enceladus. Cassini’s final close Enceladus flyby will take place on December 19 when the spacecraft will measure the amount of heat coming from the moon’s interior. The flyby will be at an altitude of 3,106 miles (4,999km). Source http://www.astronomy.com/
-
In a just-held briefing, NASA says that Pluto's "heart" will be named for the dwarf planet's original discoverer, a dark spot on moon Charon is called "Mordor," and Pluto is a relative newborn. This shot shows just one tiny sector of Pluto's surface in amazing detail. And there's much more to come. Tuesday, the New Horizons spacecraft thrilled us with the first high-quality shot the world had ever seen of Pluto. We were promised that there would soon be another image of even greater quality, and that's what NASA just delivered at a press conference at the Johns Hopkins Applied Physics Lab. The image above shows an incredibly zoomed-in shot of the bottom portion of Pluto. According to NASA's science mission chief, John Grunsfeld, at this resolution it would be possible to see the JHAPL were it on the planet's surface. While there are no buildings on Pluto, thanks to the new image, the researchers were able to see that the planet does have icy mountains stretching as high as 11,000 feet. Perhaps even more significantly, because of the lack of impact craters in this area of the planet, the team is surmising that Pluto is relatively young -- probably less than 100 million years old. In addition to the new shot of Pluto, NASA also released this image of its moon Charon. The dark spot at the top of Pluto's moon Charon is being called "Mordor." Mission Operations Manager Alice Bowman said that the shot "blew our socks off." She then went on to explain some of the features in the image. She said the dark spot at the top of the moon -- which the team is informally calling "Mordor," after the black volcanic plane in the "Lord of the Rings" tales -- is likely a thin veneer. In the southwest area, Bowman said, a series of troughs and cliffs are visible that extend for 600 miles across the moon, and at approximately the two o'clock spot on Charon's edge, a canyon plunging four to six miles deep is also visible. "There is so much science in this image alone," Bowman said, promising that an image that will have five times the resolution is coming soon. A slightly smaller bit of news is that the following image was also released, of Pluto's moon Hydra. It might not look like much to you or me, but it's pretty good considering New Horizons was 400,000 miles away when it was taken. Though it's not as captivating as the other shots being returned by New Horizons, it was enough for NASA researchers to pinpoint the moon's size, which they'd thought could have been anywhere between 20 to 100 miles across. Turns out that it's 28 x 19 miles, so "Hydra is not a planet," as Hal Weaver, New Horizons project scientist, joked. Source http://www.cnet.com/
-
Using a superpowerful telescope at the La Silla Observatory in Chile -- part of the European Southern Observatory (ESO) -- a team of international astronomers has just identified a planet with a "very similar mass to Jupiter" orbiting a sunlike star called HIP 11915. What's more, the Jupiter-like planet is almost exactly the same distance from its star as Jupiter itself is from ours. And HIP 11915 is also about the same age as our sun. This could all mean that the team has discovered what could be "a complete Solar System 2.0," to quote Jorge Melendez, of the Universidade de São Paulo, Brazil, who was the leader of the team and co-author of a paper in Astronomy and Astrophysics (PDF) that details the findings. Finding a Jupiter-like planet so far from its central sun is unusual, as such gas giants are usually found much closer in. In a theory released earlier this year (and reported by Space.com), a team of astronomers postulated that the planet Jupiter was a critical component in the formation of our solar system. They say that Jupiter might have acted as a sort of wrecking ball that first swung in toward the sun, helping form the inner rocky planets from the debris it left in its wake, and then swung back out as it was pulled by Saturn's gravity. Therefore, identifying another solar system with the same basic setup between a sun and a Jupiterish planet could be a good sign. In fact, according to an ESO statement about the research, HIP 11915 "is one of the most promising candidates so far to host a planetary system similar to our own." It's also located 186 light years away from Earth, so if it does wind up having life like ours, it'll be quite a jaunt to go see our interstellar cousins. In making their discovery, the astronomers used the planet-hunting tool known as HARPS (High Accuracy Radial velocity Planet Searcher) on the ESO 3.6-meter telescope at La Silla. They determined the planet's existence by observing the wobble it creates on its host star as it revolves around it. The ESO says that more observations will be conducted to "confirm and constrain" the discovery. Source http://www.cnet.com/ -
There's reason to believe that other planets might be better for supporting life as we know it, and they might not even be that far off, cosmically speaking. It's popular to talk about how wonderful, beautiful and rare a treasure our planet is; I certainly say such things all the time, and many satellite, Instagram and Pinterest photos testify to this truism. But let's be real for a minute, my fellow humans and A.I. beings -- we don't really have firsthand experience with an adequate sample size of habitable planets to say this for sure. In fact, a pair of scientists have been looking into the possibility that there might be a distant planet (or a couple of them or maybe 3 billion) out there more suitable to supporting life as we know it. They even describe what such a "superhabitable" planet might look like -- a super-Earth with a mass double or triple that of our planet, orbiting in the habitable zone around a K-type dwarf star several billion years older than our sun. The basic explanation for why such a planet would make a "better Earth" is that it might have a long-lasting magnetic field, which protects the planet from the abundant radiation of space and stars, and plate tectonics activity, which keeps some of the key life-supporting elements in balance. Also, a planet with double or triple the mass of Earth would mean more surface gravity, likely forming more shallow lakes and oceans, more archipelago-like land masses and fewer deserts. More shallow waters might mean more biodiversity, as they typically do here on our planet. Source http://www.cnet.com/
