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Sep 30, 2018

The Lonely Neutron Star in Supernova E0102 72.3 The Lonely Neutron Star in Supernova E0102 72.3


Why is this neutron star off-center? Recently a lone neutron star has been found within the debris left over from an old supernova explosion. The "lonely neutron star" in question is the blue dot at the center of the red nebula near the bottom left of E0102-72.3. In the featured image composite, blue represents X-ray light captured by NASA's Chandra Observatory, while red and green represent optical light captured by ESO's Very Large Telescope in Chile and NASA's Hubble Space Telescope in orbit. The displaced position of this neutron star is unexpected since the dense star is thought to be the core of the star that exploded in the supernova and created the outer nebula. It could be that the neutron star in E0102 was pushed away from the nebula's center by the supernova itself, but then it seems odd that the smaller red ring remains centered on the neutron star. Alternatively, the outer nebula could have been expelled during a different scenario -- perhaps even involving another star. Future observations of the nebulas and neutron star appear likely to resolve the situation. via NASA https://ift.tt/2DDSt7b

Sep 29, 2018

55 Nights with Saturn 55 Nights with Saturn


For 55 consecutive nights Mediterranean skies were at least partly clear this summer, from the 1st of July to the 24th of August 2018. An exposure from each night was incorporated in this composited telephoto and telescopic image to follow bright planet Saturn as it wandered through the generous evening skies. Through August, the outer planet's seasonal apparent retrograde motion slowed and drifted to the right, framed by a starry background. That brought it near the line-of-sight to the central Milky Way, and the beautiful Lagoon (M8) and Trifid (20) nebulae. Of course Saturn's largest moon Titan was also along for the ride. Swinging around the gas giant in a 16 day long orbit, Titan's resulting wave-like motion is easier to spot when the almost-too-bright Saturn is digitally edited from the scene. via NASA https://ift.tt/2P1qe3H

Sep 27, 2018

M33: Triangulum Galaxy M33: Triangulum Galaxy


The small, northern constellation Triangulum harbors this magnificent face-on spiral galaxy, M33. Its popular names include the Pinwheel Galaxy or just the Triangulum Galaxy. M33 is over 50,000 light-years in diameter, third largest in the Local Group of galaxies after the Andromeda Galaxy (M31), and our own Milky Way. About 3 million light-years from the Milky Way, M33 is itself thought to be a satellite of the Andromeda Galaxy and astronomers in these two galaxies would likely have spectacular views of each other's grand spiral star systems. As for the view from planet Earth, this sharp image shows off M33's blue star clusters and pinkish star forming regions along the galaxy's loosely wound spiral arms. In fact, the cavernous NGC 604 is the brightest star forming region, seen here at about the 7 o'clock position from the galaxy center. Like M31, M33's population of well-measured variable stars have helped make this nearby spiral a cosmic yardstick for establishing the distance scale of the Universe. via NASA https://ift.tt/2QdpBUN

Sep 26, 2018

The Suns Spectrum with its Missing Colors The Suns Spectrum with its Missing Colors


It is still not known why the Sun's light is missing some colors. Here are all the visible colors of the Sun, produced by passing the Sun's light through a prism-like device. The spectrum was created at the McMath-Pierce Solar Observatory and shows, first off, that although our white-appearing Sun emits light of nearly every color, it does indeed appear brightest in yellow-green light. The dark patches in the above spectrum arise from gas at or above the Sun's surface absorbing sunlight emitted below. Since different types of gas absorb different colors of light, it is possible to determine what gasses compose the Sun. Helium, for example, was first discovered in 1870 on a solar spectrum and only later found here on Earth. Today, the majority of spectral absorption lines have been identified - but not all. via NASA https://ift.tt/2OQxUWg

Sep 25, 2018

Highlights of the North Autumn Sky Highlights of the North Autumn Sky


What can you see in the night sky this season? The featured graphic gives a few highlights for Earth's northern hemisphere. Viewed as a clock face centered at the bottom, early (northern) autumn sky events fan out toward the left, while late autumn events are projected toward the right. Objects relatively close to Earth are illustrated, in general, as nearer to the cartoon figure with the telescope at the bottom center -- although almost everything pictured can be seen without a telescope. As happens during any season, constellations appear the same year to year, and, as usual, the Leonids meteor shower will peak in mid-November. Also as usual, the International Space Station (ISS) can be seen, at times, as a bright spot drifting across the sky after sunset. Planets visible after sunset this autumn include Jupiter and Mars, and during late autumn, Saturn. via NASA https://ift.tt/2QUpFK9

Sep 24, 2018

Rover 1A Hops on Asteroid Ryugu Rover 1A Hops on Asteroid Ryugu


Two small robots have begun hopping around the surface of asteroid Ryugu. The rovers, each the size of a small frying pan, move around the low gravity of kilometer-sized 162173 Ryugu by hopping, staying aloft for about 15 minutes and typically landing again several meters away. On Saturday, Rover 1A returned an early picture of its new home world, on the left, during one of its first hops. On Friday, lander MINERVA-II-1 detached from its mothership Hayabusa2, dropped Rovers 1A and 1B, and then landed on Ryugu. Studying Ryugu could tell humanity not only about Ryugu's surface and interior, but about what materials were available in the early Solar System for the development of life. Two more hopping rovers are planned for release, and Hayabusa2 itself is scheduled to collect a surface sample from Ryugu and return it to Earth for detailed analysis before 2021. via NASA https://ift.tt/2NybBIq

Sep 23, 2018

Equinox: Analemma over the Callanish Stones Equinox: Analemma over the Callanish Stones


Does the Sun return to the same spot on the sky every day at the same time? No. A more visual answer to that question is an analemma, a composite image taken from the same spot at the same time over the course of a year. The featured analemma was composed from images taken every few days at 4 pm near the village of Callanish in the Outer Hebrides in Scotland, UK. In the foreground are the Callanish Stones, a stone circle built around 2700 BC during humanity's Bronze Age. It is not known if the placement of the Callanish Stones has or had astronomical significance. The ultimate causes for the figure-8 shape of this an all analemmas are the tilt of the Earth axis and the ellipticity of the Earth's orbit around the Sun. At the solstices, the Sun will appear at the top or bottom of an analemma. Equinoxes, however, correspond to analemma middle points -- not the intersection point. Today at 1:54 am (UT) is the equinox ("equal night"), when day and night are equal over all of planet Earth. Many cultures celebrate a change of season at an equinox. via NASA https://ift.tt/2xwcFCm

Sep 21, 2018

Irregular Galaxy NGC 55 Irregular Galaxy NGC 55


Irregular galaxy NGC 55 is thought to be similar to the Large Magellanic Cloud (LMC). But while the LMC is about 180,000 light-years away and is a well known satellite of our own Milky Way Galaxy, NGC 55 is more like 6 million light-years distant and is a member of the Sculptor Galaxy Group. Classified as an irregular galaxy, in deep exposures the LMC itself resembles a barred disk galaxy. Spanning about 50,000 light-years, NGC 55 is seen nearly edge-on though, presenting a flattened, narrow profile in contrast with our face-on view of the LMC. Just as large star forming regions create emission nebulae in the LMC, NGC 55 is also seen to be producing new stars. This highly detailed galaxy portrait highlights a bright core crossed with dust clouds, telltale pinkish star forming regions, and young blue star clusters in NGC 55. via NASA https://ift.tt/2ptuZYh

Sep 20, 2018

Stars and Dust in Corona Australis Stars and Dust in Corona Australis


Cosmic dust clouds and young, energetic stars inhabit this telescopic vista, less than 500 light-years away toward the northern boundary of Corona Australis, the Southern Crown. The dust clouds effectively block light from more distant background stars in the Milky Way. But the striking complex of reflection nebulae cataloged as NGC 6726, 6727, and IC 4812 produce a characteristic color as blue light from the region's young, hot stars is reflected by the cosmic dust. The dust also obscures from view stars still in the process of formation. At top right, smaller yellowish nebula NGC 6729 bends around young variable star R Coronae Australis. Near it, glowing arcs and loops shocked by outflows from embedded newborn stars are identified as Herbig-Haro objects. On the sky this field of view spans about 1 degree. That corresponds to almost 9 light-years at the estimated distance of the nearby star forming region. via NASA https://ift.tt/2OAWKsX

Sep 19, 2018

Cocoon Nebula Deep Field Cocoon Nebula Deep Field


Inside the Cocoon Nebula is a newly developing cluster of stars. The cosmic Cocoon on the upper right also punctuates a long trail of obscuring interstellar dust clouds to its left. Cataloged as IC 5146, the beautiful nebula is nearly 15 light-years wide, located some 3,300 light years away toward the northern constellation of the Swan (Cygnus). Like other star forming regions, it stands out in red, glowing, hydrogen gas excited by young, hot stars and blue, dust-reflected starlight at the edge of a nearly invisible molecular cloud. In fact, the bright star near the center of this nebula is likely only a few hundred thousand years old, powering the nebular glow as it slowly clears out a cavity in the molecular cloud's star forming dust and gas. This exceptionally deep color view of the Cocoon Nebula traces tantalizing features within and surrounding the dusty stellar nursery. via NASA https://ift.tt/2QJTGfs

Sep 18, 2018

Salt Pepper and Ice Salt Pepper and Ice


There's a "camera" comet now moving across the sky. Just a bit too dim to see with the unaided eye, Comet 21P / Giacobini-Zinner has developed a long tail that makes it a good sight for binoculars and sensitive cameras. The movement of the Comet 21P on the sky was captured last week in the featured time-lapse video compressing 90 minutes into about 2.5 seconds. What might seem odd is that the 21P's tail is not following the comet's movement. This is because comet tails always point away from the Sun, and the comet was not moving toward the Sun during the period photographed. Visible far in the background on the upper left is the Salt & Pepper star cluster, M37, while the bright red star V440 Auriga is visible just about the frame's center. This 2-km ball of dust-shedding ice passed its nearest to the Sun and Earth only last week and is now fading as it crosses into southern skies. Comet 21P should remain visible, however, and photogenic to stabilized cameras, for another month or so. via NASA https://ift.tt/2xljwOS

Sep 17, 2018

Cosmic Collision Forges Galactic Ring Cosmic Collision Forges Galactic Ring


How could a galaxy become shaped like a ring? The rim of the blue galaxy pictured on the right is an immense ring-like structure 150,000 light years in diameter composed of newly formed, extremely bright, massive stars. That galaxy, AM 0644-741, is known as a ring galaxy and was caused by an immense galaxy collision. When galaxies collide, they pass through each other -- their individual stars rarely come into contact. The ring-like shape is the result of the gravitational disruption caused by an entire small intruder galaxy passing through a large one. When this happens, interstellar gas and dust become condensed, causing a wave of star formation to move out from the impact point like a ripple across the surface of a pond. The likely intruder galaxy is on the left of this combined image from Hubble (visible) and Chandra (X-ray) space telescopes. X-ray light is shown in pink and depicts places where energetic black holes or neutron stars, likely formed shortly after the galaxy collision, reside. via NASA https://ift.tt/2MFwI60

Sep 15, 2018

Mont Blanc, Meteor, and Milky Way Mont Blanc, Meteor, and Milky Way


Snowy Mont Blanc is near the center of this atmospheric night skyscape. But high, thin clouds fogged the skies at the photographer's location, looking south toward Europe's highest peak from the southern Swiss Alps. Still, the 13 second exposure finds the faint star fields and dark rifts of the Milky Way above the famous white mountain. Bloated by the mist, bright planet Saturn and Antares (right), alpha star of Scorpius, shine through the clouds to flank the galaxy's central bulge. The high-altitude scene is from the rewarding night of August 12/13, so it also includes the green trail of a Perseid meteor shooting along the galactic plane. via NASA https://ift.tt/2xegZGt

Sep 14, 2018

Ice Halos at Yellowknife Ice Halos at Yellowknife


You've probably seen a circle around the Sun before. More common than rainbows, ice halos, like a 22 degree circular halo for example, can be easy to spot, especially if you can shade your eyes from direct sunlight. Still it's rare to see such a diverse range of ice halos, including sundogs, tangent, infralateral, and Parry arcs, all found in this snapshot from planet Earth. The picture was quickly taken in the late morning of September 4 from Yellowknife, Northwest Territories, Canada. The beautiful patterns are generated as sunlight (or moonlight) is reflected and refracted in six-sided water ice crystals in Earth's atmosphere. Of course, atmospheric ice halos in the skies of other worlds are likely to be different. via NASA https://ift.tt/2MumLIF

Sep 13, 2018

Comet, Clusters, and Nebulae Comet, Clusters, and Nebulae


Bright enough for binocular viewing Comet 21P / Giacobini-Zinner stands out, even in this deep telephoto mosaic of the star cluster and nebula rich constellation Auriga the Charioteer. On the night of September 9 its greenish coma and diffuse tail contrast with the colorful stars and reddish emission nebulae in the almost 10 degree field of view along the Milky Way. The comet was near its perihelion and closest approach to Earth, about 200 light-seconds away. Riding across the distant background just above the comet's tail are well-known Auriga star clusters M38 (left of center) and M36 (toward the right) about 4,000 light-years away. At the top left, emission region IC 405 is only 1,500 light-years distant, more dramatically known as the Flaming Star Nebula. To its right lies IC 410, 12,000 light-years away and famous for its star-forming cosmic tadpoles. A child of our Solar System Giacobini-Zinner is a periodic comet orbiting the Sun once every 6.5 years, and the parent body of October's Draconids meteor shower. via NASA https://ift.tt/2x93nLD

Sep 12, 2018

Lunations Lunations


Our Moon's appearance changes nightly. As the Moon orbits the Earth, the half illuminated by the Sun first becomes increasingly visible, then decreasingly visible. The featured video animates images taken by NASA's Moon-orbiting Lunar Reconnaissance Orbiter to show all 12 lunations that appear this year, 2018. A single lunation describes one full cycle of our Moon, including all of its phases. A full lunation takes about 29.5 days, just under a month (moon-th). As each lunation progresses, sunlight reflects from the Moon at different angles, and so illuminates different features differently. During all of this, of course, the Moon always keeps the same face toward the Earth. What is less apparent night-to-night is that the Moon's apparent size changes slightly, and that a slight wobble called a libration occurs as the Moon progresses along its elliptical orbit. via NASA https://ift.tt/2x1jU52

Sep 11, 2018

Milky Way over Trolls Tongue Milky Way over Trolls Tongue


You have to take a long hike to see the Troll's Tongue -- ten hours over rocky terrain. And in this case, it took three trips to capture the landform below a clear night sky. Trolltunga itself is a picturesque rock protrusion extending about 700 meters over mountainous cliffs near Lake Ringedalsvatnet in Norway. The overhang is made of billion-year-old Precambrian bedrock that was carved out by glaciers during an ice-age about 10,000 years ago. The featured picture is a composite of two exposures, a 15-second image of the foreground Earth followed 40 minutes later by an 87-second exposure of the background sky. Thousands of discernable stars dot the backdrop starscape in addition to billions of unresolved stars in the nearly vertical band of our Milky Way Galaxy. via NASA https://ift.tt/2x4r0or

Sep 10, 2018

Curiosity Vista from Vera Rubin Ridge Curiosity Vista from Vera Rubin Ridge


If you could stand on Mars -- what might you see? If you were NASA's Curiosity rover, just last month you would have seen the view from Vera Rubin Ridge, an intriguing rock-strewn perch on the side of Mount Sharp. In the featured 360-degree panorama, you can spin around and take in the vista from all directions, in many browsers, just by pointing or tilting. In this virtual reality view, many instruments on the rover are labelled, including antennas, the robotic arm, and the radioisotope thermoelectric generator (RTG). Dark sand and light rock cover the ground nearby in a mixture called lakebed mudstone. Towering Mount Sharp is only barely visible in the distance due to airborne dust from a planet-wide storm just winding down. Among its many discoveries, Curiosity has found that the raw ingredients for life are present on Mars. Next on Mars will be NASA's Insight, on target to land in late November, which is scheduled to deploy a seismometer to better study the interior of the red planet. via NASA https://ift.tt/2oVTpcY

Sep 9, 2018

M1: The Crab Nebula from Hubble M1: The Crab Nebula from Hubble


This is the mess that is left when a star explodes. The Crab Nebula, the result of a supernova seen in 1054 AD, is filled with mysterious filaments. The filaments are not only tremendously complex, but appear to have less mass than expelled in the original supernova and a higher speed than expected from a free explosion. The featured image, taken by the Hubble Space Telescope, is presented in three colors chosen for scientific interest. The Crab Nebula spans about 10 light-years. In the nebula's very center lies a pulsar: a neutron star as massive as the Sun but with only the size of a small town. The Crab Pulsar rotates about 30 times each second. via NASA https://ift.tt/2NXDR35

Sep 7, 2018

Saturn s North Polar Hexagon Saturn s North Polar Hexagon


In full view, the amazing six-sided jet stream known as Saturn's north polar hexagon is shown in this colorful Cassini image. Extending to 70 degrees north latitude, the false-color video frame is map-projected, based on infrared, visible, and ultraviolet image data recorded by the Saturn-orbiting spacecraft in late 2012. First found in the outbound Voyager flyby images from the 1980s, the bizarre, long-lived feature tied to the planet's rotation is about 30,000 kilometers across. At its center lies the ringed gas giant's hurricane-like north polar storm. A new long term study of Cassini data has found a remarkable higher-altitude vortex, exactly matching the outlines of the north polar hexagon, that formed as summer approached the planet's northern hemisphere. It appears to reach hundreds of kilometers above these deeper cloud tops, into Saturn's stratosphere. via NASA https://ift.tt/2Q6nP8y

Sep 6, 2018

Along the Western Veil Along the Western Veil


Delicate in appearance, these filaments of shocked, glowing gas, are draped across planet Earth's sky toward the constellation of Cygnus. They form the western part of the Veil Nebula. The Veil Nebula itself is a large supernova remnant, an expanding cloud born of the death explosion of a massive star. Light from the original supernova explosion likely reached Earth over 5,000 years ago. Blasted out in the cataclysmic event, the interstellar shock wave plows through space sweeping up and exciting interstellar material. The glowing filaments are really more like long ripples in a sheet seen almost edge on, remarkably well separated into atomic hydrogen (red) and oxygen (blue-green) gas. Also known as the Cygnus Loop, the Veil Nebula now spans nearly 3 degrees or about 6 times the diameter of the full Moon. While that translates to over 70 light-years at its estimated distance of 1,500 light-years, this telescopic two panel mosaic image of the western portion spans about half that distance. Brighter parts of the western Veil are recognized as separate nebulae, including The Witch's Broom (NGC 6960) along the top of this view and Pickering's Triangle (NGC 6979) below and left. via NASA https://ift.tt/2NlbeQf

Sep 5, 2018

NGC 3682: Sideways Spiral Galaxy NGC 3682: Sideways Spiral Galaxy


What do spiral galaxies look like sideways? Featured is a sharp telescopic view of a magnificent edge-on spiral galaxy NGC 3628, a puffy galactic disk divided by dark dust lanes. Of course, this deep galactic portrait puts some astronomers in mind of its popular moniker, The Hamburger Galaxy. The tantalizing island universe is about 100,000 light-years across and 35 million light-years away in the northern springtime constellation Leo. NGC 3628 shares its neighborhood in the local Universe with two other large spirals M65 and M66 in a grouping otherwise known as the Leo Triplet. Gravitational interactions with its cosmic neighbors are likely responsible for the extended flare and warp of this spiral's disk. via NASA https://ift.tt/2wHNYmi

Sep 3, 2018

Aurora around Saturns North Pole Aurora around Saturns North Pole


Are Saturn's auroras like Earth's? To help answer this question, the Hubble Space Telescope and the Cassini spacecraft monitored Saturn's North Pole simultaneously during Cassini's final orbits around the gas giant in September 2017. During this time, Saturn's tilt caused its North Pole to be clearly visible from Earth. The featured image is a composite of ultraviolet images of aurora and optical images of Saturn's clouds and rings, all taken recently by Hubble. Like on Earth, Saturn's northern auroras can make total or partial rings around the pole. Unlike on Earth, however, Saturn's auroras are frequently spirals -- and more likely to peak in brightness just before midnight and dawn. In contrast to Jupiter's auroras, Saturn's auroras appear better related to connecting Saturn's internal magnetic field to the nearby, variable, solar wind. Saturn's southern auroras were similarly imaged back in 2004 when the planet's South Pole was clearly visible to Earth. via NASA https://ift.tt/2NIcNox

Sep 2, 2018

A Powerful Solar Flare A Powerful Solar Flare


It was one of the most powerful solar flares in recorded history. Occurring in 2003 and seen across the electromagnetic spectrum, the Sun briefly became over 100 times brighter in X-rays than normal. The day after this tremendous X 17 solar flare -- and subsequent Coronal Mass Ejection (CME) -- energetic particles emitted from the explosions struck the Earth, creating auroras and affecting satellites. The spacecraft that took these frames -- SOHO -- was put in a turtle-like safe mode to avoid further damage from this and subsequent solar particle storms. The featured time-lapse movie condenses into 10 seconds events that occurred over 4 hours. The CME, visible around the central sun-shade, appears about three-quarters of the way through the video, while frames toward the very end are progressively noisier as protons from the explosions strike SOHO's LASCO detector. One this day in 1859, the effects of an even more powerful solar storm caused telegraphs on Earth to spark in what is known as the Carrington Event. Powerful solar storms such as these may create beautiful aurora-filled skies, but they also pose a real danger as they can damage satellites and even power grids across the Earth. via NASA https://ift.tt/2NEaX8a

Sep 1, 2018


On August 23, 2018 the identification and distribution of aerosols in the Earth's atmosphere is shown in this dramatic, planet-wide visualization. Produced in real time, the Goddard Earth Observing System Forward Processing (GEOS FP) model relies on a combination of Earth-observing satellite and ground-based data to calculate the presence of types of aerosols, tiny solid particles and liquid droplets, as they circulate above the entire planet. This August 23rd model shows black carbon particles in red from combustion processes, like smoke from the fires in the United States and Canada, spreading across large stretches of North America and Africa. Sea salt aerosols are in blue, swirling above threatening typhoons near South Korea and Japan, and the hurricane looming near Hawaii. Dust shown in purple hues is blowing over African and Asian deserts. The location of cities and towns can be found from the concentrations of lights based on satellite image data of the Earth at night. via NASA https://ift.tt/2orIqHS