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Astronomy Picture of the Day (General/Chat)

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  • Astronomy Picture of the Day - CG4: The Globule and the Galaxy (I missed posting this yesterday)

    05/22/2024 12:54:57 PM PDT · by MtnClimber · 6 replies
    NASA ^ | 21 May, 2024 | Image Credit: CTIO, NOIRLab, DOE, NSF, AURA; Processing: T. A. Rector (U. Alaska Anchorage/NSF’s NOI
    Explanation: Can a gas cloud eat a galaxy? It's not even close. The "claw" of this odd looking "creature" in the featured photo is a gas cloud known as a cometary globule. This globule, however, has ruptured. Cometary globules are typically characterized by dusty heads and elongated tails. These features cause cometary globules to have visual similarities to comets, but in reality they are very much different. Globules are frequently the birthplaces of stars, and many show very young stars in their heads. The reason for the rupture in the head of this object is not yet known. The galaxy...
  • Astronomy Picture of the Day - Green Aurora over Sweden

    05/22/2024 12:40:21 PM PDT · by MtnClimber · 8 replies
    NASA ^ | 22 May, 2024 | Image Credit & Copyright: Göran Strand
    Explanation: It was bright and green and stretched across the sky. This striking aurora display was captured in 2016 just outside of Östersund, Sweden. Six photographic fields were merged to create the featured panorama spanning almost 180 degrees. Particularly striking aspects of this aurora include its sweeping arc-like shape and its stark definition. Lake Storsjön is seen in the foreground, while several familiar constellations and the star Polaris are visible through the aurora, far in the background. Coincidently, the aurora appears to avoid the Moon visible on the lower left. The aurora appeared a day after a large hole opened...
  • Astronomy Picture of the Day - Aurora Dome Sky

    05/20/2024 12:46:22 PM PDT · by MtnClimber · 11 replies
    NASA ^ | 20 May, 2024 | Image Credit & Copyright: Xuecheng Liu & Yuxuan Liu
    Explanation: It seemed like night, but part of the sky glowed purple. It was the now famous night of May 10, 2024, when people over much of the world reported beautiful aurora-filled skies. The featured image was captured this night during early morning hours from Arlington, Wisconsin, USA. The panorama is a composite of several 6-second exposures covering two thirds of the visible sky, with north in the center, and processed to heighten the colors and remove electrical wires. The photographer (in the foreground) reported that the aurora appeared to flow from a point overhead but illuminated the sky only...
  • Astronomy Picture of the Day - Jupiter Diving

    05/19/2024 1:11:52 PM PDT · by MtnClimber · 5 replies
    NASA ^ | 19 May, 2024 | Animated Video Credit: NASA, JPL-Caltech, SwRI, MSSS, Gerald Eichstadt, Justin Cowart
    Explanation: Take this simulated plunge and dive into the upper atmosphere of Jupiter, the Solar System's ruling gas giant. The awesome animation is based on image data from JunoCam, and the microwave radiometer on board the Jupiter-orbiting Juno spacecraft. Your view will start about 3,000 kilometers above the southern Jovian cloud tops, and you can track your progress on the display at the left. As altitude decreases, temperature increases while you dive deeper at the location of Jupiter's famous Great Red Spot. In fact, Juno data indicates the Great Red Spot, the Solar System's largest storm system, penetrates some 300...
  • Astronomy Picture of the Day - North Celestial Aurora

    05/18/2024 12:48:01 PM PDT · by MtnClimber · 5 replies
    NASA ^ | 18 May, 2024 | Image Credit & Copyright: Chirag Upreti
    Explanation: Graceful star trail arcs reflect planet Earth's daily rotation in this colorful night skyscape. To create the timelapse composite, on May 12 consecutive exposures were recorded with a camera fixed to a tripod on the shores of the Ashokan Reservoir, in the Catskills region of New York, USA. North star Polaris is near the center of the star trail arcs. The broad trail of a waxing crescent Moon is on the left, casting a strong reflection across the reservoir waters. With intense solar activity driving recent geomagnetic storms, the colorful aurora borealis or northern lights, rare to the region,...
  • Astronomy Picture of the Day - Aurora Banks Peninsula

    05/17/2024 11:25:03 AM PDT · by MtnClimber · 8 replies
    Nasa ^ | 17 May, 2024 | Image Credit & Copyright: Kavan Chay
    Explanation: This well-composed composite panoramic view looks due south from Banks Peninsula near Christchurch on New Zealand's South Island. The base of a tower-like rocky sea stack is awash in the foreground, with stars of the Southern Cross at the top of the frame and planet Earth's south celestial pole near center. Still, captured on May 11, vibrant aurora australis dominate the starry southern sea and skyscape. The shimmering southern lights were part of extensive auroral displays that entertained skywatchers in northern and southern hemispheres around planet Earth, caused by intense geomagnetic storms. The extreme spaceweather was triggered by the...
  • Astronomy Picture of the Day - Aurora Georgia

    05/16/2024 11:38:39 AM PDT · by MtnClimber · 8 replies
    NASA ^ | 16 May, 2024 | Image Credit & Copyright: Wright Dobbs
    Explanation: A familiar sight from Georgia, USA, the Moon sets near the western horizon in this rural night skyscape. Captured on May 10 before local midnight, the image overexposes the Moon's bright waxing crescent at left in the frame. A long irrigation rig stretches across farmland about 15 miles north of the city of Bainbridge. Shimmering curtains of aurora shine across the starry sky, definitely an unfamiliar sight for southern Georgia nights. Last weekend, extreme geomagnetic storms triggered by the recent intense activity from solar active region AR 3664 brought epic displays of aurora, usually seen closer to the poles,...
  • Astronomy Picture of the Day - AR 3664 at the Sun's Edge

    05/15/2024 2:14:37 PM PDT · by MtnClimber · 9 replies
    NASA ^ | 15 May, 2024 | Image Credit & Copyright: Sebastian Voltmer
    Explanation: What did the monster active region that created the recent auroras look like when at the Sun's edge? There, AR 3664 better showed its 3D structure. Pictured, a large multi-pronged solar prominence was captured extending from chaotic sunspot region AR 3664 out into space, just one example of the particle clouds ejected from this violent solar region. The Earth could easily fit under this long-extended prominence. The featured image was captured two days ago from this constantly changing region. Yesterday, the strongest solar flare in years was expelled (not shown), a blast classified in the upper X-class. Ultraviolet light...
  • Astronomy Picture of the Day - The 37 Cluster

    05/14/2024 12:55:16 PM PDT · by MtnClimber · 10 replies
    NASA ^ | 14 May, 2024 | Image Credit & Copyright: Sergio Eguivar
    Explanation: For the mostly harmless denizens of planet Earth, the brighter stars of open cluster NGC 2169 seem to form a cosmic 37. Did you expect 42? From our perspective, the improbable numerical asterism appears solely by chance. It lies at an estimated distance of 3,300 light-years toward the constellation Orion. As far as galactic or open star clusters go, NGC 2169 is a small one, spanning about 7 light-years. Formed at the same time from the same cloud of dust and gas, the stars of NGC 2169 are only about 11 million years old. Such clusters are expected to...
  • Astronomy Picture of the Day - Red Aurora over Poland

    05/12/2024 11:56:28 AM PDT · by MtnClimber · 13 replies
    NASA ^ | 12 May, 2024 | Image Credit & Copyright: Mariusz Durlej
    Explanation: Northern lights don't usually reach this far south. Magnetic chaos in the Sun's huge Active Region 3664, however, produced a surface explosion that sent a burst of electrons, protons, and more massive, charged nuclei into the Solar System. A few days later, that coronal mass ejection (CME) impacted the Earth and triggered auroras that are being reported unusually far from our planet's north and south poles. The free sky show might not be over -- the sunspot rich AR3664 has ejected even more CMEs that might also impact the Earth tonight or tomorrow. That active region is now near...
  • Astronomy Picture of the Day - AR 3664: Giant Sunspot Group

    05/11/2024 1:03:20 PM PDT · by MtnClimber · 12 replies
    NASA ^ | 11 May, 2024 | Image Credit & Copyright: Franco Fantasia & Guiseppe Conzo (Gruppo Astrofili Palidoro)
    Explanation: Right now, one of the largest sunspot groups in recent history is crossing the Sun. Active Region 3664 is not only big -- it's violent, throwing off clouds of particles into the Solar System. Some of these CMEs are already impacting the Earth, and others might follow. At the extreme, these solar storms could cause some Earth-orbiting satellites to malfunction, the Earth's atmosphere to slightly distort, and electrical power grids to surge. When impacting Earth's upper atmosphere, these particles can produce beautiful auroras, with some auroras already being reported unusually far south. Pictured here, AR3664 and its dark sunspots...
  • Astronomy Picture of the Day - Simulation: Two Black Holes Merge

    05/10/2024 12:03:39 PM PDT · by MtnClimber · 7 replies
    NASA ^ | 10 May, 2024 | Simulation Credit: Simulating eXtreme Spacetimes Project
    Explanation: Relax and watch two black holes merge. Inspired by the first direct detection of gravitational waves in 2015, this simulation plays in slow motion but would take about one third of a second if run in real time. Set on a cosmic stage, the black holes are posed in front of stars, gas, and dust. Their extreme gravity lenses the light from behind them into Einstein rings as they spiral closer and finally merge into one. The otherwise invisible gravitational waves generated as the massive objects rapidly coalesce cause the visible image to ripple and slosh both inside and...
  • Astronomy Picture of the Day - The Galaxy, the Jet, and a Famous Black Hole

    05/09/2024 12:11:39 PM PDT · by MtnClimber · 8 replies
    NASA ^ | 9 May, 2024 | Image Credit: NASA, JPL-Caltech, Event Horizon Telescope Collaboration
    Explanation: Bright elliptical galaxy Messier 87 (M87) is home to the supermassive black hole captured in 2017 by planet Earth's Event Horizon Telescope in the first ever image of a black hole. Giant of the Virgo galaxy cluster about 55 million light-years away, M87 is rendered in blue hues in this infrared image from the Spitzer Space telescope. Though M87 appears mostly featureless and cloud-like, the Spitzer image does record details of relativistic jets blasting from the galaxy's central region. Shown in the inset at top right, the jets themselves span thousands of light-years. The brighter jet seen on the...
  • Astronomy Picture of the Day - Visualization: A Black Hole Accretion Disk

    05/08/2024 12:45:52 PM PDT · by MtnClimber · 7 replies
    NASA ^ | 8 May, 2024 | Visualization Credit: NASA’s Goddard Space Flight Center, Jeremy Schnittman
    Explanation: What would it look like to circle a black hole? If the black hole was surrounded by a swirling disk of glowing and accreting gas, then the great gravity of the black hole would deflect light emitted by the disk to make it look very unusual. The featured animated video gives a visualization. The video starts with you, the observer, looking toward the black hole from just above the plane of the accretion disk. Surrounding the central black hole is a thin circular image of the orbiting disk that marks the position of the photon sphere -- inside of...
  • Astronomy Picture of the Day - Black Hole Accreting with Jet (illustration)

    05/07/2024 12:22:44 PM PDT · by MtnClimber · 28 replies
    NASA ^ | 7 May, 2024 | Illustration Credit: NASA, Swift, Aurore Simonnet (Sonoma State U.)
    Explanation: What happens when a black hole devours a star? Many details remain unknown, but observations are providing new clues. In 2014, a powerful explosion was recorded by the ground-based robotic telescopes of the All Sky Automated Survey for SuperNovae (Project ASAS-SN), with followed-up observations by instruments including NASA's Earth-orbiting Swift satellite. Computer modeling of these emissions fit a star being ripped apart by a distant supermassive black hole. The results of such a collision are portrayed in the featured artistic illustration. The black hole itself is a depicted as a tiny black dot in the center. As matter falls...
  • Astronomy Picture of the Day - A Total Solar Eclipse from Sliver to Ring

    05/06/2024 1:48:39 PM PDT · by MtnClimber · 4 replies
    NASA ^ | 6 May, 2024 | Video Credit & Copyright: Reinhold Wittich; Music: Sunrise from Also sprach Zarathusra (R. Strauss)
    Explanation: This is how the Sun disappeared from the daytime sky last month. The featured time-lapse video was created from stills taken from Mountain View, Arkansas, USA on 2024 April 8. First, a small sliver of a normally spotted Sun went strangely dark. Within a few minutes, much of the background Sun was hidden behind the advancing foreground Moon. Within an hour, the only rays from the Sun passing the Moon appeared like a diamond ring. During totality, most of the surrounding sky went dark, making the bright pink prominences around the Sun's edge stand out, and making the amazing...
  • Astronomy Picture of the Day - A Black Hole Disrupts a Passing Star

    05/05/2024 1:02:38 PM PDT · by MtnClimber · 15 replies
    NASA ^ | 5 May, 2024 | Illustration Credit: NASA, JPL-Caltech
    Explanation: What happens to a star that goes near a black hole? If the star directly impacts a massive black hole, then the star falls in completely -- and everything vanishes. More likely, though, the star goes close enough to have the black hole's gravity pull away its outer layers, or disrupt, the star. Then, most of the star's gas does not fall into the black hole. These stellar tidal disruption events can be as bright as a supernova, and an increasing amount of them are being discovered by automated sky surveys. In the featured artist's illustration, a star has...
  • Astronomy Picture of the Day - 3 ATs

    05/04/2024 4:16:29 PM PDT · by MtnClimber · 7 replies
    NASA ^ | 4 May, 2024 | Image Credit & Copyright: Yuri Beletsky (Carnegie Las Campanas Observatory, TWAN)
    Explanation: Despite their resemblance to R2D2, these three are not the droids you're looking for. Instead, the enclosures house 1.8 meter Auxiliary Telescopes (ATs) at Paranal Observatory in the Atacama Desert region of Chile. The ATs are designed to be used for interferometry, a technique for achieving extremely high resolution observations, in concert with the observatory's 8 meter Very Large Telescope units. A total of four ATs are operational, each fitted with a transporter that moves the telescope along a track allowing different arrays with the large unit telescopes. To work as an interferometer, the light from each telescope is...
  • Astronomy Picture of the Day - Temperatures on Exoplanet WASP-43b

    05/03/2024 2:09:59 PM PDT · by MtnClimber · 9 replies
    NASA ^ | 3 May, 2024 | Illustration Credit: NASA, ESA, CSA, Ralf Crawford (STScI) Science: Taylor Bell (BAERI), Joanna Bars
    Explanation: A mere 280 light-years from Earth, tidally locked, Jupiter-sized exoplanet WASP-43b orbits its parent star once every 0.8 Earth days. That puts it about 2 million kilometers (less than 1/25th the orbital distance of Mercury) from a small, cool sun. Still, on a dayside always facing its parent star, temperatures approach a torrid 2,500 degrees F as measured at infrared wavelengths by the MIRI instrument on board the James Webb Space Telescope. In this illustration of the hot exoplanet's orbit, Webb measurements also show nightside temperatures remain above 1,000 degrees F. That suggests that strong equatorial winds circulate the...
  • Astronomy Picture of the Day - M100: A Grand Design Spiral Galaxy

    05/02/2024 1:27:10 PM PDT · by MtnClimber · 18 replies
    NASA ^ | 2 May, 2024 | Image Credit & Copyright: Drew Evans
    Explanation: Majestic on a truly cosmic scale, M100 is appropriately known as a grand design spiral galaxy. The large galaxy of over 100 billion stars has well-defined spiral arms, similar to our own Milky Way. One of the brightest members of the Virgo Cluster of galaxies, M100, also known as NGC 4321 is 56 million light-years distant toward the well-groomed constellation Coma Berenices. In this telescopic image, the face-on grand design spiral shares a nearly 1 degree wide field-of-view with slightly less conspicuous edge-on spiral NGC 4312 (at upper right). The 21 hour long equivalent exposure from a dark sky...