Confirmed Muon Wobble Remains Unexplained

How fast do elementary particles wobble? A surprising answer to this seemingly inconsequential question came out of Brookhaven National Laboratory in New York, USA in 2001, and indicated that the Standard Model of Particle Physics, adopted widely in physics, is incomplete. Specifically, the muon, a particle with similarities to a heavy electron, has had its relatively large wobble under scrutiny in a series of experiments known as g-2 (gee-minus-two). The Brookhaven result galvanized other experimental groups around the world to confirm it, and pressured theorists to better understand it. Reporting in last week, the most sensitive muon wobble experiment yet, conducted at Fermi National Accelerator Laboratory (Fermilab) in Illinois and pictured here, agreed with the Brookhaven result. The unexpected wobble rate may indicate that an ever-present sea of virtual particles includes types not currently known. Alternatively, it may indicate that flaws exist in difficult theoretical prediction calculations. Future runs at Fermilab’s g-2 experiment will further increase precision and, possibly, the statistical difference between the universe we measure and the universe we understand. via NASA https://ift.tt/2OH3k6u

Alnitak and the Flame Nebula

What lights up the Flame Nebula? Fifteen hundred light years away towards the constellation of Orion lies a nebula which, from its glow and dark dust lanes, appears, on the left, like a billowing fire. But fire, the rapid acquisition of oxygen, is not what makes this Flame glow. Rather the bright star Alnitak, the easternmost star in the Belt of Orion visible on the far left, shines energetic light into the Flame that knocks electrons away from the great clouds of hydrogen gas that reside there. Much of the glow results when the electrons and ionized hydrogen recombine. The featured picture of the Flame Nebula (NGC 2024) was taken across three visible color bands with detail added by a long duration exposure taken in light emitted only by hydrogen. The Flame Nebula is part of the Orion Molecular Cloud Complex, a star-forming region that includes the famous Horsehead Nebula. via NASA https://ift.tt/3uOFGoh

When Black Holes Collide

What happens when two black holes collide? This extreme scenario occurs in the centers of many merging galaxies and multiple star systems. The featured video shows a computer animation of the final stages of such a merger, while highlighting the gravitational lensing effects that would appear on a background starfield. The black regions indicate the event horizons of the dynamic duo, while a surrounding ring of shifting background stars indicates the position of their combined Einstein ring. All background stars not only have images visible outside of this Einstein ring, but also have one or more companion images visible on the inside. Eventually the two black holes coalesce. The end stages of such a merger is now known to produce a strong blast of gravitational radiation, providing a new way to see our universe. via NASA https://ift.tt/3fZiWgS

Zodiacal Night

An intense band of zodiacal light is captured in this serene mountain and night skyscape from April 7. The panoramic view was recorded after three hours of hiking from a vantage looking west after sunset across the Pyrenees in southern France. At 2838 meters altitude, Mont Valier is the tallest peak near center. In the sky above, the familiar stars of Orion and the northern winter Milky Way are approaching the rugged western horizon. At the shoulder of Orion, Betelgeuse is one of three bright yellowish celestial beacons. It forms a triangle with fellow red giant star Aldebaran located below Betelgeuse and to the right, and the red planet Mars. Mars shines just under the band of the Milky Way, still immersed in the bright zodiacal light. via NASA https://ift.tt/2RpeSMT

Messier 106

Close to the Great Bear (Ursa Major) and surrounded by the stars of the Hunting Dogs (Canes Venatici), this celestial wonder was discovered in 1781 by the metric French astronomer Pierre Mechain. Later, it was added to the catalog of his friend and colleague Charles Messier as M106. Modern deep telescopic views reveal it to be an island universe – a spiral galaxy around 30 thousand light-years across located only about 21 million light-years beyond the stars of the Milky Way. Along with a bright central core, this stunning galaxy portrait, a composite of image data from amateur and professional telescopes, highlights youthful blue star clusters and reddish stellar nurseries tracing the galaxy’s spiral arms. It also shows off remarkable reddish jets of glowing hydrogen gas. In addition to small companion galaxy NGC 4248 at bottom right, background galaxies can be found scattered throughout the frame. M106, also known as NGC 4258, is a nearby example of the Seyfert class of active galaxies, seen across the spectrum from radio to X-rays. Active galaxies are powered by matter falling into a massive central black hole. via NASA https://ift.tt/3d3UrNM

3D Ingenuity

The multicolor, stereo imaging Mastcam-Z on the Perseverance rover zoomed in to captured this 3D close-up (get out your red/blue glasses) of the Mars Ingenuity helicopter on mission sol 45, April 5. That’s only a few sols before the technology demonstrating Ingenuity will attempt to fly in the thin martian atmosphere, making the first powered flight on another planet. The historic test flight is planned for no earlier than Sunday, April 11. Casting its shadow on the martian surface, Ingenuity is standing alone on four landing legs next to the rover’s wheel tracks. The experimental helicopter’s solar panel, charging batteries that keep it warm through the cold martian nights and power its flight, sits above its two 1.2 meter (4 foot) long counter-rotating blades. via NASA https://ift.tt/3cYdwRu

Threads of NGC 1947

Found in far southern skies, deep within the boundaries of the constellation Dorado, NGC 1947 is some 40 million light-years away. In silhouette against starlight, obscuring lanes of cosmic dust thread across the peculiar galaxy’s bright central regions. Unlike the rotation of stars, gas, and dust tracing the arms of spiral galaxies, the motions of dust and gas don’t follow the motions of stars in NGC 1947 though. Their more complicated disconnected motion suggest this galaxy’s visible threads of dust and gas may have come from a donor galaxy, accreted by NGC 1947 during the last 3 billion years or so of the peculiar galaxy’s evolution. With spiky foreground Milky Way stars and even more distant background galaxies scattered through the frame, this sharp Hubble image spans about 25,000 light-years near the center of NGC 1947. via NASA https://ift.tt/3mn75KU

Mars and the Pleiades Beyond Vinegar Hill

Is this just a lonely tree on an empty hill? To start, perhaps, but look beyond. There, a busy universe may wait to be discovered. First, physically, to the left of the tree, is the planet Mars. The red planet, which is the new home to NASA’s Perseverance rover, remains visible this month at sunset above the western horizon. To the tree’s right is the Pleiades, a bright cluster of stars dominated by several bright blue stars. The featured picture is a composite of several separate foreground and background images taken within a few hours of each other, early last month, from the same location on Vinegar Hill in Milford, Nova Scotia, Canada. At that time, Mars was passing slowly, night after night, nearly in front of the distant Seven Sisters star cluster. The next time Mars will pass angularly as close to the Pleiades as it did in March will be in 2038. via NASA https://ift.tt/3cRMawk

Veil Nebula: Wisps of an Exploded Star

Wisps like this are all that remain visible of a Milky Way star. About 7,000 years ago that star exploded in a supernova leaving the Veil Nebula. At the time, the expanding cloud was likely as bright as a crescent Moon, remaining visible for weeks to people living at the dawn of recorded history. Today, the resulting supernova remnant, also known as the Cygnus Loop, has faded and is now visible only through a small telescope directed toward the constellation of the Swan (Cygnus). The remaining Veil Nebula is physically huge, however, and even though it lies about 1,400 light-years distant, it covers over five times the size of the full Moon. The featured picture is a Hubble Space Telescope mosaic of six images together covering a span of only about two light years, a small part of the expansive supernova remnant. In images of the complete Veil Nebula, even studious readers might not be able to identify the featured filaments. via NASA https://ift.tt/39Jot7n

In, Through, and Beyond Saturn’s Rings

Four moons are visible on the featured image — can you find them all? First — and farthest in the background — is Titan, the largest moon of Saturn and one of the larger moons in the Solar System. The dark feature across the top of this perpetually cloudy world is the north polar hood. The next most obvious moon is bright Dione, visible in the foreground, complete with craters and long ice cliffs. Jutting in from the left are several of Saturn’s expansive rings, including Saturn’s A ring featuring the dark Encke Gap. On the far right, just outside the rings, is Pandora, a moon only 80-kilometers across that helps shepherd Saturn’s F ring. The fourth moon? If you look closely inside Saturn’s rings, in the Encke Gap, you will find a speck that is actually Pan. Although one of Saturn’s smallest moons at 35-kilometers across, Pan is massive enough to help keep the Encke gap relatively free of ring particles. After more than a decade of exploration and discovery, the Cassini spacecraft ran low on fuel in 2017 and was directed to enter Saturn’s atmosphere, where it surely melted. via NASA https://ift.tt/39HnCEd