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SOFIA Observations of Ceres Show You Can’t Judge an Asteroid by Its Cover(ing)

Animated sequence of images from NASA's Dawn spacecraft showing northern terrain on the sunlit side of Ceres. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Animated sequence of Ceres from NASA’s Dawn spacecraft. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

The dwarf planet Ceres, at 587 miles wide the largest object in the main asteroid belt between Mars and Jupiter, has a different surface composition than previously thought—and it took NASA and DLR’s Boeing 747-based SOFIA observatory to make the distinction. By observing Ceres in mid-infrared, only possible from high altitudes above infrared-absorbing water vapor, SOFIA found that Ceres is covered in silicates—pyroxenes—that likely came from impacts, the result of infalling material from elsewhere in the asteroid belt…the “dust” of asteroid collisions.

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Cassini Has Just Taken the Best Picture of Daphnis Yet!

Image of Daphnis captured by Cassini on Jan. 18, 2017. (NASA/JPL-Caltech/SSI)

Image of Daphnis captured by Cassini on Jan. 16, 2017. (NASA/JPL-Caltech/SSI)

Hello, Daphnis! On January 16, 2017, the Cassini spacecraft captured the best photo yet of Daphnis, a 5-mile-wide shepherd moon that orbits Saturn inside the Keeler Gap at the outermost edge of the A ring (and also just so happens to be my personal favorite moon of Saturn!) The raw image arrived on Earth today, and it’s just beautiful.

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This is Jupiter Seen from Mars

Jupiter and its four largest moons imaged by the HiRISE camera in orbit around Mars on Jan. 11, 2007. (NASA/JPL/University of Arizona)

Jupiter and its four largest moons imaged by the HiRISE camera in orbit around Mars on Jan. 11, 2007. (NASA/JPL/University of Arizona)

The HiRISE camera aboard NASA’s Mars Reconnaissance Orbiter (MRO) is specifically designed to take super high-resolution images of the surface of Mars but it also does a pretty darn good job capturing pictures of other objects too—like Jupiter and its Galilean moons, several hundred million miles away! The image above was captured in expanded color (that is, it includes wavelengths in infrared) by HiRISE on January 11, 2007, and shows the giant planet from Mars orbit.

Mars and Jupiter were at opposition at the time, only about 345 million miles apart.

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Could This Asteroid Hit Earth? Astronomers Go “Back in Time” to Find the Answer

Potentially hazardous asteroid 2016 WJ1 was discovered in Oct. 2016—but also in July 2003. Credit: Canada-France-Hawaii Telescope

Astronomers are always watching the skies for observations of near-Earth asteroids—”space rocks” that have orbits close to Earth’s and, in the case of potentially hazardous asteroids (aka PHAs), those whose orbits could actually cross Earth’s and are larger than 150 meters (500 ft) across. When a new one of these is discovered—no small feat considering that many are very dark, move quickly, and could really be anywhere in the sky—it’s a scramble to determine the object’s orbital parameters and figure out just how close it can get to us and when. Such was the case on Oct. 19, 2016, when the asteroid 2016 WJ1 was identified with the Catalina Sky Survey. This object, estimated to be anywhere from 110 to 340 meters across—easily within the potentially hazardous range—was initially calculated to pose a threat in 2065 with a possible impact risk, albeit a very small one. Eventually though, scientists were able to refine the risk chance with more observations of 2016 WJ1…observations that had actually occurred over 13 years earlier.

Read the full story from ESA here: Asteroid sleuths go back to the future

Asteroid 16 Psyche Could Truly Be a Psychedelic Little World—AND Worth Quadrillions

Artist’s rendering of the metal asteroid 16 Psyche. (Credit: Arizona State University)

NASA recently announced the go-ahead for a new Discovery-level mission that would send a spacecraft to explore 16 Psyche, a 130-mile-wide asteroid in the Solar System’s main belt between Mars and Jupiter. 16 Psyche is a relatively small world but is made almost entirely of metals—some of them what we’d consider precious on Earth, like nickel, gold, and platinum—and not only would that make it a fantastic-looking place with mountainous ridges of nickel and valleys filled with green olivine and yellow sulfur deposits, but also incredibly valuable…some estimates place 16 Psyche as “worth” up to $10,000 quadrillion.

Yes that’s quadrillion, as in one thousand trillion. (And times ten thousand!)

Read the rest of this story by Irene Klotz on Seeker here: Step Aside Iron Man, NASA’s Going to Explore a Strange Iron World

Light and Dark: the Two Faces of Dione

Global map of Dione’s surface. NASA/JPL-Caltech/SSI/LPI

Saturn’s moon Dione (pronounced DEE-oh-nee) is a heavily-cratered, 700-mile-wide world of ice and rock, its surface slashed by signature “wispy lines” that mark the bright faces of sheer ice cliffs. But Dione has some strange colorations too, evident here in a global map created in 2014 from Cassini images. Its leading half—the side that faces “forward” as it moves around Saturn in its tidally-locked orbit—is pale and bright, while its trailing hemisphere is stained a brownish color, the result of surface interaction with  charged particles in Saturn’s magnetic field.

Read more from ESA here: Space in Images – Global colour mosaic of Dione and see more pictures and news about Dione here.

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