Tom's Astronomy Blog 18 Jul 2017, 04:32 UTC We are just two months from the end of the Cassini mission! NASA – Enceladus’ intriguing south-polar jets are viewed from afar, backlit by sunlight while the moon itself glows softly in reflected Saturn-shine. Observations of the jets taken from various viewing geometries provide different insights into these remarkable features. Cassini has gathered a wealth of information in the hopes of unraveling the mysteries of the subsurface ocean that lurks beneath the moon’s icy crust. This view looks toward the Saturn-facing hemisphere of Enceladus (313 miles or 504 kilometers across). North is up. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on April 13, 2017. The view was acquired at a distance of approximately 502,000 miles (808,000 kilometers) from Enceladus and at a sun-Enceladus-spacecraft, or phase, angle of 176 degrees. Image scale is 3 miles (5 kilometers) per pixel. Image Credit: NASA/JPL-Caltech/Space Science Institute
Clean Room Tour with NASA’s Next Gen Tracking Data Relay Satellite TDRS-M, Closeout Incident Under Review – Photos17 Jul 2017, 20:14 UTC The last of NASA’s next generation Tracking and Data Relay Satellites (TRDS) designed to relay critical science data and research observations gathered by the International Space Station (ISS), Hubble and dozens of Earth-orbiting Earth science missions is undergoing final prelaunch clean room preparations on the Florida Space Coast while targeting an early August launch – even as the agency reviews the scheduling impact of a weekend closeout incident that damaged a key component. Liftoff of NASA’s $400 million TDRS-M science relay comsat atop a United Launch Alliance (ULA) Atlas V rocket currently scheduled for August 3 may be in doubt following a July 14 work related incident causing damage to the satellite’s Omni S-band antenna while inside the Astrotech Space Operations facility in Titusville, Florida.
io9 Space 17 Jul 2017, 19:00 UTC Pluto’s moon Charon is the best sidekick a dwarf planet could hope for: unwavering in its loyalty, content to be a minor character in somebody else’s narrative. But two years after the New Horizons flyby, the largest of Pluto’s five moons is finally getting some well-deserved time in the spotlight. New research suggests that Charon’s storied history includes tectonic activity, cryovolcanism, and perhaps, a globe-spanning ocean.
Centauri Dreams 17 Jul 2017, 17:14 UTC The Laser SETI campaign we looked at on Friday is one aspect of a search for intelligent life in the universe that is being addressed in many ways. In addition to optical methods, we look of course at radio wavelengths, and as we begin to characterize the atmospheres of rocky exoplanets, we’ll also look for signs of atmospheric modification that could indicate industrial activity. But we have to be careful. Because SETI looks for evidence of alien technology, it is a search for civilizations about whose possible activities we know absolutely nothing.
Starts With A Bang! 17 Jul 2017, 14:32 UTC If you’ve never seen a total solar eclipse before, you’ve likely heard about many of the features to look for, like the sky darkening during the day, the Sun disappearing, and the solar corona and, occasionally, stars becoming visible during the day. But if you take an enhanced view, either with binoculars, a telescope, or photography, so much more becomes apparent.
astrobites 17 Jul 2017, 13:45 UTC Title: Testing the white dwarf mass-radius relationship with eclipsing binaries Authors: S. G. Parsons, B. T. Gänsicke, T. R. Marsh et al. First Author’s Institution: Department of Physics and Astronomy, University of Sheffield, UK Status: Accepted to MNRAS [open access] Look outside your window. Can you see the Sun? If it’s night-time, just pick a random star instead. Our Sun one day will become a white dwarf star, and the chance that the random star you’ve picked will follow the same path is over 95%. White dwarfs are by far the most common final evolutionary state for a star. The famous supernovas actually only occur when a star is massive enough to burn elements heavier than helium in its core, and that is usually not the case. What happens instead is that the star can only produce elements up to carbon and oxygen, and then nuclear reactions in the core cease to occur. With no release of energy to counteract the gravitational force, the carbon-oxygen core will contract more and more until it becomes degenerate. This degenerate core is essentially the white dwarf, which becomes visible when the outer layers of the star are ejected on its final breadth of ...
Across the Universe 17 Jul 2017, 00:53 UTC Jupiter’s Great Red Spot (Enhanced Color): This enhanced-color image of Jupiter’s Great Red Spot was created by citizen scientist Gerald Eichstädt using data from the JunoCam imager on NASA’s Juno spacecraft. Original enclosures: ACROSS THE UNIVERSE