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Showing posts with the label December 21

APOD: Sun Halo at Sixty three Degrees North

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Happy Solstice! Today is the December solstice, marking an astronomical beginning of summer in the southern hemisphere and winter in the north. On its yearly trek through planet Earth's skies, at this solstice the Sun reaches its southern most declination, 23.5 degrees south, at 21:48 UTC. About 4 days ago the Sun was near this seasonal southern limit and so only just above the horizon at local noon over Ostersund in central Sweden. This view looking over the far northern lakeside city finds the midday Sun with a beautiful solar ice halo. Naturally occurring atmospheric ice crystals can produce the tantalizing halo displays, refracting and reflecting the sunlight through their hexagonal geometry. Still, with the Sun low and near the horizon in the clear sky, likely sources of the ice crystals producing this intense halo are snow cannons. Operating at a local ski area, the snowmaking machines create a visible plume at the top of the nearby island Froson toward the right side of the...
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APOD: Solstice Sun and Milky Way

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Welcome to December's solstice, first day of winter in the north and summer for the southern hemisphere. Astronomical markers of the seasons, solstice and equinox dates are based on the Sun's place in its annual journey along the ecliptic, through planet Earth's sky. At this solstice, the Sun reaches its maximum southern declination of -23.5 degrees today at 15:59 UTC, while its right ascension coordinate on the celestial sphere is 18 hours. That puts the Sun in the constellation Sagittarius in a direction near the center of our Milky Way galaxy. In fact, if you could see today's Solstice Sun against faint background stars and nebulae (that's really hard to do, especially in the daytime ...) your view might look something like this composited panorama. To make it, images of our fair galaxy were taken under dark Namibian night skies, then stitched together in a panoramic view. From a snapshot made on 2015 December 21, the Sun was digitally overlayed as a brilliant s...
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Space News: ESA awards €10.45 million to two UK launch startups

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by Andrew Parsonson VALLETTA, Malta — The European Space Agency awarded UK-based launch startups Orbex and Skyrora a combined €10.45 million ($12.35 million) to support development of competing microlaunchers. The two support contracts announced March 24 were awarded under Boost!, an ESA program that aims to foster new commercial space transportation services. The agency adopted Boost! during Space19+, an ESA ministerial-level council meeting held in November 2019, and announced an open call for proposals last April. Each of the two new Boost! contracts outlines specific outcomes the funding will assist the companies in achieving. Orbital Launch Express (Orbex) is developing its two-stage Prime microlauncher which is powered by 3D-printed rocket engines and is designed to carry payloads of up 150 kilograms to low Earth orbit. The vehicle is expected to make its debut in 2022. The €7.45 million in co-funding Orbex and its partners received is the largest Boost! award to date. The...
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APOD:

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Most photographs don't adequately portray the magnificence of the Sun's corona. Seeing the corona first-hand during a total solar eclipse is unparalleled. The human eye can adapt to see coronal features and extent that average cameras usually cannot. Welcome, however, to the digital age. The featured image digitally combined short and long exposures taken in Exmouth, Australia that were processed to highlight faint and extended features in the corona during the total solar eclipse that occurred in April of 2023. Clearly visible are intricate layers and glowing caustics of an ever changing mixture of hot gas and magnetic fields in the Sun's corona. Looping prominences appear bright pink just past the Sun's edge. Images taken seconds before and after the total eclipse show glimpses of the background Sun known as Baily's Beads and diamond ring effect. The next total solar eclipse will cross North America in April of 2024. via NASA https://ift.tt/ibLzpTC
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APOD: Spiral Galaxy NGC 2841

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A mere 46 million light-years distant, spiral galaxy NGC 2841 can be found in planet Earth's night sky toward the northern constellation of Ursa Major. This sharp image centered on the gorgeous island universe also captures spiky foreground Milky Way stars and more distant background galaxies within the same telescopic field of view. It shows off the bright nucleus of NGC 2841, along with its inclined galactic disk, and faint outer regions. Dust lanes, small star-forming regions, and young star clusters are embedded in the galaxy's patchy, tightly wound spiral arms. In contrast, many other spirals exhibit broader, sweeping arms with large star-forming regions. NGC 2841 has a diameter of over 150,000 light-years, making it even larger than our own Milky Way. X-ray images suggest that extreme outflows from giant stars and stellar explosions create plumes of hot gas extending into a halo around NGC 2841. via NASA https://ift.tt/HDshMQ9
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