Summer to Winter Milky Way

Taken near local midnight, this autumn night’s panorama follows the arch of the Milky Way across the northern horizon from the High Fens, Eifel Nature Park at the border of Belgium and Germany. Shift your gaze across the wetlands from west to east (left to right) and you can watch stars once more prominent in northern summer give way to those that will soon dominate northern winter nights. Setting, wanderer Mars is brightest at the far left, still shinning against almost overwhelming city lights along the southwestern horizon. Bright stars Altair, Deneb, and Vega form the northern sky’s summer triangle, straddling the Milky Way left of center. Part of the winter hexagon Capella and Aldebaran, along with the beautiful Pleiades star cluster shine across the northeastern sky. The line-of-sight along the hikers boardwalk leads almost directly toward the Big Dipper, an all season asterism from these northern latitudes. Follow the Big Dipper’s pointer stars to Polaris and the north celestial pole nearly centered above it. Andromeda, the other large galaxy in the skyscape, is near the top of the frame. [via NASA] https://ift.tt/2NP5Ml4
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Cherenkov Telescope at Sunset

On October 10, a new telescope reflected the light of the setting Sun. With dark horizon above and sunset colors below, its segmented mirror inverts an image of the beautiful evening sky in this snapshot from the Roque del Los Muchachos Observatory on the Canary Island of La Palma. The mirror segments cover a 23 meter diameter and are mounted in the open structure of the Large Scale Telescope 1, inaugurated as the first component of the Cherenkov Telescope Array (CTA). Most ground-based telescopes are hindered by the atmosphere that blurs, scatters, and absorbs light. But cherenkov telescopes are designed to detect very high energy gamma rays and actually require the atmosphere to operate. As the gamma rays impact the upper atmosphere they produce air showers of high-energy particles. A large, fast camera at the common focus images the brief flashes of optical light, called Cherenkov light, created by the air shower particles. The flashes reveal the incoming gamma ray timing, direction, and energy. Ultimately more than 100 Cherenkov telescopes are planned for the CTA at locations in both northern and southern hemispheres on planet Earth. [via NASA] https://ift.tt/2AggvBy

Jupiter in Ultraviolet from Hubble

Jupiter looks a bit different in ultraviolet light. To better interpret Jupiter’s cloud motions and to help NASA’s robotic Juno spacecraft understand the planetary context of the small fields that it sees, the Hubble Space Telescope is being directed to regularly image the entire Jovian giant. The colors of Jupiter being monitored go beyond the normal human visual range to include both ultraviolet and infrared light. Featured from 2017, Jupiter appears different in near ultraviolet light, partly because the amount of sunlight reflected back is distinct, giving differing cloud heights and latitudes discrepant brightnesses. In the near UV, Jupiter’s poles appear relatively dark, as does its Great Red Spot and a smaller (optically) white oval to the right. The String of Pearl storms farther to the right, however, are brightest in near ultraviolet, and so here appear (false-color) pink. Jupiter’s largest moon Ganymede appears on the upper left. Juno continues on its looping 53-day orbits around Jupiter, while Earth-orbiting Hubble is now recovering from the loss of a stabilizing gyroscope. [via NASA] https://ift.tt/2OpUXec

Orion in Red and Blue

When did Orion become so flashy? This colorful rendition of part of the constellation of Orion comes from red light emitted by hydrogen and sulfur (SII), and blue-green light emitted by oxygen (OIII). Hues on the featured image were then digitally reassigned to be indicative of their elemental origins — but also striking to the human eye. The breathtaking composite was painstakingly composed from hundreds of images which took nearly 200 hours to collect. Pictured, Barnard’s Loop, across the image bottom, appears to cradle interstellar constructs including the intricate Orion Nebula seen just right of center. The Flame Nebula can also be quickly located, but it takes a careful eye to identify the slight indentation of the dark Horsehead Nebula. As to Orion’s flashiness — a leading explanation for the origin of Barnard’s Loop is a supernova blast that occurred about two million years ago. [via NASA] https://ift.tt/2OpgeF4

Skygazers on the Beach

Kona, a young boxer, is a dog who loves splashing in the waves along Solana Beach near San Diego, planet Earth. But he paused here, at least briefly, during an early evening romp on October 7. Along with two people friends he gazes skyward in this snapshot, dazzled by the flight of a Falcon 9 rocket. Their seaside view is of the sunlit exhaust plumes from the rocket’s first stage thrusters as it returns to Vandenberg Air Force base, its launch site over 250 miles to the north. [via NASA] https://ift.tt/2EqIJ0C

The Falcon 9 Nebula

Not the Hubble Space Telescope’s latest view of a distant planetary nebula, this illuminated cloud of gas and dust dazzled even casual U.S. west coast skygazers on October 7. Taken about three miles north of Vandenberg Air Force Base, the image follows plumes and exhaust from the first and second stage of a SpaceX Falcon 9 rocket rising through southern California’s early evening skies. In the fading twilight, the reddish smoke drifting in the foreground at the right is from the initial ascent of the rocket. The expanding blue and orange filamentary plumes are from first and second stage separation and the first stage boostback burn, still in sunlight at extreme altitudes. But the bright spot below center is the second stage itself headed almost directly away from the camera, accelerating to orbital velocity and far downrange. Pulsed thrusters form the upside down V-shape at the top as they guide the reusable Falcon 9 first stage back to the landing site. [via NASA] https://ift.tt/2QHTs83