NASA's Jet Propulsion Laboratory News and Features 21 Nov 2017, 18:36 UTC In a fitting farewell to the planet that had been its home for over 13 years, the Cassini spacecraft took one last, lingering look at Saturn and its splendid rings during the final leg of its journey and snapped a series of images that has been assembled into a new mosaic.
NASA's Goddard Space Flight Center 21 Nov 2017, 17:00 UTC When comet 45P zipped past Earth early in 2017, researchers observing from NASA’s Infrared Telescope Facility, or IRTF, in Hawai’i gave the long-time trekker a thorough astronomical checkup. The results help fill in crucial details about ices in Jupiter-family comets and reveal that quirky 45P doesn’t quite match any comet studied so far.
NAOJ Top News 21 Nov 2017, 04:00 UTC Using the Subaru Telescope atop Maunakea, researchers have identified 11 dwarf galaxies and two star-containing halos in the outer region of a large spiral galaxy 25 million light-years away from Earth. The findings, published in The Astrophysical Journal, provide new insight into how these 'tidal stellar streams' form around galaxies.
NASA's Jet Propulsion Laboratory News and Features 20 Nov 2017, 16:15 UTC Dark features on Mars previously considered evidence for subsurface flowing of water are interpreted by new research as granular flows, where grains of sand and dust slip downhill to make dark streaks, rather than the ground being darkened by seeping water. Continuing examination of these still-perplexing seasonal dark streaks with a powerful camera on NASA's Mars Reconnaissance Orbiter (MRO) shows they exist only on slopes steep enough for dry grains to descend the way they do on faces of active dunes.
ESO Top News 20 Nov 2017, 16:00 UTC For the first time ever astronomers have studied an asteroid that has entered the Solar System from interstellar space. Observations from ESO’s Very Large Telescope in Chile and other observatories around the world show that this unique object was traveling through space for millions of years before its chance encounter with our star system. It appears to be a dark, reddish, highly-elongated rocky or high-metal-content object. The new results appear in the journal Nature on 20 November 2017.
NASA's Goddard Space Flight Center 20 Nov 2017, 14:04 UTC The historic chamber’s massive door opening brings to a close about 100 days of testing for Webb, a significant milestone in the telescope’s journey to the launch pad. The cryogenic vacuum test began when the chamber was sealed shut on July 10, 2017. Scientists and engineers at Johnson put Webb’s optical telescope and integrated science instrument module (OTIS) through a series of tests designed to ensure the telescope functioned as expected in an extremely cold, airless environment akin to that of space.
Stellar Astrophysics Centre at the University of Aarhus 20 Nov 2017, 08:52 UTC In a recent paper published online on arXiv and due to be published in its final version in Monthly Notices of the Royal Astronomical Society, a group of researchers with Vincent van Eylen as lead author, and most co-authors connected to SAC, tell the story of the "Radius Valley" amongst rocky exoplanets and with new and more precise measurements explain why we may have to lower the number of prospective earthlike rocky planets. The paper, titeled "An asteroseismic view of the radius valley: stripped cores, not born rocky" can be found here in the arXive version. ScienceNews has an exellent overview of the results, and a somewhat shorter resume appears here from the University of Leiden, where Vincent now resides. A resume in Danish can be found in the news column from the Department of Physics and Astronomy, Aarhus University (IFA).
ESA Top News 20 Nov 2017, 08:30 UTC ESA’s Integral space observatory has been orbiting Earth for 15 years, observing the ever-changing, powerful and violent cosmos in gamma rays, X-rays and visible light. Studying stars exploding as supernovas, monster black holes and, more recently, even gamma-rays that were associated with gravitational waves, Integral continues to broaden our understanding of the high-energy Universe.