Sharpless 308: Star Bubble Sharpless 308: Star Bubble

Blown by fast winds from a hot, massive star, this cosmic bubble is huge. Cataloged as Sharpless 2-308 it lies some 5,200 light-years away toward the constellation of the Big Dog (Canis Major) and covers slightly more of the sky than a Full Moon. That corresponds to a diameter of 60 light-years at its estimated distance. The massive star that created the bubble, a Wolf-Rayet star, is the bright one near the center of the nebula. Wolf-Rayet stars have over 20 times the mass of the Sun and are thought to be in a brief, pre-supernova phase of massive star evolution. Fast winds from this Wolf-Rayet star create the bubble-shaped nebula as they sweep up slower moving material from an earlier phase of evolution. The windblown nebula has an age of about 70,000 years. Relatively faint emission captured in the expansive image is dominated by the glow of ionized oxygen atoms mapped to a blue hue. SH2-308 is also known as The Dolphin Nebula. via NASA https://go.nasa.gov/2SfJfnB

Wide Field View of Great American Eclipse Wide Field View of Great American Eclipse

Only in the fleeting darkness of a total solar eclipse is the light of the solar corona easily visible. Normally overwhelmed by the bright solar disk, the expansive corona, the sun's outer atmosphere, is an alluring sight. But the subtle details and extreme ranges in the corona's brightness, although discernible to the eye, are notoriously difficult to photograph. Pictured here, however, using over 120 images and meticulous digital processing, is a detailed wide-angle image of the Sun's corona taken during the Great American Eclipse in 2017 August. Clearly visible are intricate layers and glowing caustics of an ever changing mixture of hot gas and magnetic fields. Hundreds of stars as faint as 11th magnitude are visible behind the Moon and Sun, with Mars appearing in red on the far right. The next total eclipse of the Sun will occur on July 2 and be visible during sunset from a thin swath across Chile and Argentina. via NASA https://go.nasa.gov/2TnnUG4

Ultima Thule from New Horizons Ultima Thule from New Horizons

How do distant asteroids differ from those near the Sun? To help find out, NASA sent the robotic New Horizons spacecraft past the classical Kuiper belt object 2014 MU69, nicknamed Ultima Thule, the farthest asteroid yet visited by a human spacecraft. Zooming past the 30-km long space rock on January 1, the featured image is the highest resolution picture of Ultima Thule's surface beamed back so far. Utima Thuli does look different than imaged asteroids of the inner Solar System, as it shows unusual surface texture, relatively few obvious craters, and nearly spherical lobes. Its shape is hypothesized to have formed from the coalescence of early Solar System rubble in into two objects -- Ultima and Thule -- which then spiraled together and stuck. Research will continue into understanding the origin of different surface regions on Ultima Thule, whether it has a thin atmosphere, how it obtained its red color, and what this new knowledge of the ancient Solar System tells us about the formation of our Earth. via NASA https://go.nasa.gov/2Uk6z0M

The Umbra of Earth The Umbra of Earth

The dark, inner shadow of planet Earth is called the umbra. Shaped like a cone extending into space, it has a circular cross section most easily seen during a lunar eclipse. For example, on January 21 the Full Moon slid across the northern half of Earth's umbral shadow, entertaining moonwatchers around much of the planet. In the total phase of the eclipse, the Moon was completely within the umbra for 63 minutes. Recorded under clear, dark skies from the hills near Chiuduno, Italy this composite eclipse image uses successive pictures from totality (center) and partial phases to trace out a large part of the umbra's curved edge. Reflecting sunlight scattered by the atmosphere into Earth's shadow, the lunar surface appears reddened during totality. But close to the umbra's edge, the limb of the eclipsed Moon shows a distinct blue hue. The blue eclipsed moonlight originates as rays of sunlight pass through layers high in the upper stratosphere, colored by ozone that scatters red light and transmits blue. via NASA https://go.nasa.gov/2B3vkaD

Moon Struck Moon Struck

Craters produced by ancient impacts on the airless Moon have long been a familiar sight. But only since the 1990s have observers began to regularly record and study optical flashes on the lunar surface, likely explosions resulting from impacting meteoroids. Of course, the flashes are difficult to see against a bright, sunlit lunar surface. But during the January 21 total eclipse many imagers serendipitously captured a meteoroid impact flash against the dim red Moon. Found while examining images taken shortly before the total eclipse phase began, the flash is indicated in the inset above, near the Moon's darkened western limb. Estimates based on the flash duration recorded by the Moon Impact Detection and Analysis System (MIDAS) telescopes in southern Spain indicate the impactor's mass was about 10 kilograms and created a crater between seven and ten meters in diameter. via NASA https://go.nasa.gov/2CKI9GQ

Matterhorn, Moon, and Meteor Matterhorn, Moon, and Meteor

Fans of planet Earth probably recognize the Matterhorn in the foreground of this night skyscape. Famed in mountaineering history, the 4,478 meter Alpine mountain stands next to the totally eclipsed Moon. In spite of -22 degree C temperatures, the inspired scene was captured on the morning of January 21 from the mountains near Zermatt, Switzerland. Different exposures record the dim red light reflected by the Moon fully immersed in Earth's shadow. Seen directly above the famous Alpine peak, but about 600 light-years away, are the stars of the Praesepe or Beehive star cluster also known as Messier 44. An added reward to the cold eclipse vigil, a bright and colorful meteor flashed below the temporarily dimmmed Moon, just tracing the Matterhorn's north-eastern climbing route along Hornli ridge. via NASA https://go.nasa.gov/2W7h4Gy

Orion over the Austrian Alps Orion over the Austrian Alps

Do you recognize this constellation? Through the icicles and past the mountains is Orion, one of the most identifiable star groupings on the sky and an icon familiar to humanity for over 30,000 years. Orion has looked pretty much the same during the past 50,000 years and should continue to look the same for many thousands of years into the future. Orion is quite prominent in the sky this time of year, a recurring sign of (modern) winter in Earth's northern hemisphere and summer in the south. Pictured, Orion was captured recently above the Austrian Alps in a composite of seven images taken by the same camera in the same location during the same night. Below and slightly to the right of Orion's three-star belt is the Orion Nebula, while the four bright stars surrounding the belt are, clockwise from the upper left, Betelgeuse, Bellatrix, Rigel, and Saiph. via NASA https://go.nasa.gov/2CFY0qd

Lunar Eclipse over Cologne Cathedral Lunar Eclipse over Cologne Cathedral

Why would a bright full Moon suddenly become dark? Because it entered the shadow of the Earth. That's what happened Sunday night as the Moon underwent a total lunar eclipse. Dubbed by some as a Super (because the Moon was angularly larger than usual, at least slightly) Blood (because the scattering of sunlight through the Earth's atmosphere makes an eclipsed Moon appeared unusually red) Wolf (because January full moons are sometimes called Wolf Moons from the legend that wolves like to howl at the moon) Moon Eclipse, the shadowy spectacle was visible from the half of the Earth then facing the Moon, and was captured in numerous spectacular photographs. Featured, a notable image sequence was captured over the Cologne Cathedral, a UNESCO World Heritage Site, in Cologne, Germany. The lunar eclipse sequence was composed from 68 different exposures captured over three hours during freezing temperatures -- and later digitally combined and edited to remove a cyclist and a pedestrian. The next total lunar eclipse will occur in 2021. via NASA https://go.nasa.gov/2HzN8Q2

InSight Lander Takes Selfie on Mars InSight Lander Takes Selfie on Mars

This is what NASA's Insight lander looks like on Mars. With its solar panels, InSight is about the size of a small bus. Insight successfully landed on Mars in November with a main objective to detect seismic activity. The featured selfie is a compilation of several images taken of different parts of the InSight lander, by the lander's arm, at different times. SEIS, the orange-domed seismometer seen near the image center last month, has now been placed on the Martian surface. With this selfie, Mars InSight continues a long tradition of robotic spacecraft on Mars taking and returning images of themselves, including Viking, Sojourner, Pathfinder, Spirit, Opportunity, Phoenix, and Curiosity. Data taken by Mars Insight is expected to give humanity unprecedented data involving the interior of Mars, a region thought to harbor formation clues not only about Mars, but Earth. via NASA https://go.nasa.gov/2VZDKbI

Total Lunar Eclipse at Moonset Total Lunar Eclipse at Moonset

The Moon slid through Earth's shadow on January 31, 2018 in a total lunar eclipse. In this time-lapse sequence of that eclipse from Portal, Arizona, USA, the partial eclipse starts with the Moon high in the western sky. The eclipse total phase lasted about 76 minutes, but totality ended after the dark, reddened Moon set below the horizon. The upcoming total lunar eclipse, on the night of January 20/21, will be better placed for skygazers across the Americas, though. There, all 62 minutes of the total phase, when the Moon is completely immersed in Earth's dark umbral shadow, will take place with the Moon above the horizon. Watch it if you can. The next total lunar eclipse visible from anywhere on planet Earth won't take place until May 26, 2021, and then the total eclipse will last a mere 15 minutes. via NASA https://go.nasa.gov/2CuHpW7

Cabin Under the Stars Cabin Under the Stars

Gocka's, a family nickname for the mountain cabin, and a wooden sled from a generation past stand quietly under the stars. The single exposure image was taken on January 6 from Tanndalen Sweden to evoke a simple visual experience of the dark mountain skies. A pale band of starlight along the Milky Way sweeps through the scene. At the foot of Orion the Hunter, bright star Rigel shines just above the old kicksled's handrail. Capella, alpha star of Auriga the celestial charioteer, is the brightest star at the top of the frame. In fact, the familiar stars of the winter hexagon and the Pleiades star cluster can all be found in this beautiful skyscape from a northern winter night. via NASA https://go.nasa.gov/2FEG02h

IC 342: The Hidden Galaxy IC 342: The Hidden Galaxy

Similar in size to large, bright spiral galaxies in our neighborhood, IC 342 is a mere 10 million light-years distant in the long-necked, northern constellation Camelopardalis. A sprawling island universe, IC 342 would otherwise be a prominent galaxy in our night sky, but it is hidden from clear view and only glimpsed through the veil of stars, gas and dust clouds along the plane of our own Milky Way galaxy. Even though IC 342's light is dimmed and reddened by intervening cosmic clouds, this sharp telescopic image traces the galaxy's own obscuring dust, young star clusters, and glowing pink star forming regions along spiral arms that wind far from the galaxy's core. IC 342 may have undergone a recent burst of star formation activity and is close enough to have gravitationally influenced the evolution of the local group of galaxies and the Milky Way. via NASA https://go.nasa.gov/2MeQaIj

The Heart and Soul Nebulas The Heart and Soul Nebulas

Is the heart and soul of our Galaxy located in Cassiopeia? Possibly not, but that is where two bright emission nebulas nicknamed Heart and Soul can be found. The Heart Nebula, officially dubbed IC 1805 and visible in the featured image on the bottom right, has a shape reminiscent of a classical heart symbol. The Soul Nebula is officially designated IC 1871 and is visible on the upper left. Both nebulas shine brightly in the red light of energized hydrogen. Also shown in this three-color montage is light emitted from sulfur, shown in yellow, and oxygen, shown in blue. Several young open clusters of stars are visible near the nebula centers. Light takes about 6,000 years to reach us from these nebulas, which together span roughly 300 light years. Studies of stars and clusters like those found in the Heart and Soul Nebulas have focused on how massive stars form and how they affect their environment. via NASA https://go.nasa.gov/2H9XMwQ

Meteor and Milky Way over the Alps Meteor and Milky Way over the Alps

Now this was a view with a thrill. From Mount Tschirgant in the Alps, you can see not only nearby towns and distant Tyrolean peaks, but also, weather permitting, stars, nebulas, and the band of the Milky Way Galaxy. What made the arduous climb worthwhile this night, though, was another peak -- the peak of the 2018 Perseids Meteor Shower. As hoped, dispersing clouds allowed a picturesque sky-gazing session that included many faint meteors, all while a carefully positioned camera took a series of exposures. Suddenly, a thrilling meteor -- bright and colorful -- slashed down right next the nearly vertical band of the Milky Way. As luck would have it, the camera caught it too. Therefore, a new image in the series was quickly taken with one of the sky-gazers posing on the nearby peak. Later, all of the images were digitally combined. via NASA https://go.nasa.gov/2FuPQ6U

Tychos Supernova Remnant in Xray Tychos Supernova Remnant in Xray

What star created this huge puffball? What's pictured is the hot expanding nebula of Tycho's supernova remnant, the result of a stellar explosion first recorded over 400 years ago by the famous astronomer Tycho Brahe. The featured image is a composite of three X-ray colors taken by the orbiting Chandra X-ray Observatory. The expanding gas cloud is extremely hot, while slightly different expansion speeds have given the cloud a puffy appearance. Although the star that created SN 1572, is likely completely gone, a star dubbed Tycho G, too dim to be discerned here, is thought to be a companion. Finding progenitor remnants of Tycho's supernova is particularly important because the supernova is of Type Ia, an important rung in the distance ladder that calibrates the scale of the visible universe. The peak brightness of Type Ia supernovas is thought to be well understood, making them quite valuable in exploring the relationship between faintness and farness in the distant universe. via NASA https://go.nasa.gov/2CjCcjW

Milky Way Falls Milky Way Falls

It can be the driest place on planet Earth, but water still flows in Chile's Atacama desert, high in the mountains. After discovering this small creek with running water, the photographer returned to the site to watch the Milky Way rise in the dark southern skies, calculating the moment when Milky Way and precious flowing water would meet. In the panoramic night skyscape, stars and nebulae immersed in the glow along the Milky Way itself also shared that moment with the Milky Way's satellite galaxies the Large and Small Magellanic clouds above the horizon at the right. Bright star Beta Centauri is poised at the very top of the waterfall. Above it lies the dark expanse of the Coalsack nebula and the stars of the Southern Cross. via NASA https://go.nasa.gov/2FqT1fW

Partial Eclipse over Beijing Partial Eclipse over Beijing

On January 6 the New Moon rose in silhouette with the Sun seen from northeastern Asia. Near maximum, the dramatic partial solar eclipse is captured in this telephoto view through hazy skies. In the foreground, the hill top Wanchun pavilion overlooking central Beijing's popular Forbidden City hosts eclipse-watching early morning risers. This was the first of five, three solar and two lunar, eclipses for 2019. Next up is a total lunar eclipse during this month's Full Perigee Moon. At night on January 21, that celestial shadow play will be visible from the hemisphere of planet Earth that includes the Americas, Europe, and western Africa. via NASA https://go.nasa.gov/2RpJjS7

Vela Supernova Remnant Mosaic Vela Supernova Remnant Mosaic

The plane of our Milky Way Galaxy runs through this complex and beautiful skyscape. Seen toward colorful stars near the northwestern edge of the constellation Vela (the Sails), the 16 degree wide, 200 frame mosaic is centered on the glowing filaments of the Vela Supernova Remnant, the expanding debris cloud from the death explosion of a massive star. Light from the supernova explosion that created the Vela remnant reached Earth about 11,000 years ago. In addition to the shocked filaments of glowing gas, the cosmic catastrophe also left behind an incredibly dense, rotating stellar core, the Vela Pulsar. Some 800 light-years distant, the Vela remnant is likely embedded in a larger and older supernova remnant, the Gum Nebula. Objects identified in this broad mosaic include emission and reflection nebulae, star clusters, and the remarkable Pencil Nebula. via NASA https://go.nasa.gov/2FnWdJm

Quadrantids Quadrantids

Named for a forgotten constellation, the Quadrantid Meteor Shower is an annual event for planet Earth's northern hemisphere skygazers It usually peaks briefly in the cold, early morning hours of January 4. The shower's radiant on the sky lies within the old, astronomically obsolete constellation Quadrans Muralis. That position is situated near the boundaries of the modern constellations Hercules, Bootes, and Draco. About 30 Quadrantid meteors can be counted in this skyscape composed of digital frames recorded in dark and moonless skies between 2:30am and local dawn. The shower's radiant is rising just to the right of the Canary Island of Tenerife's Teide volcano, and just below the familiar stars of the Big Dipper on the northern sky. A likely source of the dust stream that produces Quadrantid meteors was identified in 2003 as an asteroid. Look carefully and you can also spot a small, telltale greenish coma above the volcanic peak and near the top of the frame. That's the 2018 Christmas visitor to planet Earth's skies, Comet Wirtanen. via NASA https://go.nasa.gov/2GZP2sX

HESS Telescopes Explore the High Energy Sky HESS Telescopes Explore the High Energy Sky

They may look like modern mechanical dinosaurs but they are enormous swiveling eyes that watch the sky. The High Energy Stereoscopic System (H.E.S.S.) Observatory is composed of four 12-meter reflecting-mirror telescopes surrounding a larger telescope housing a 28-meter mirror. They are designed to detect strange flickers of blue light -- Cherenkov radiation --emitted when charged particles move slightly faster than the speed of light in air. This light is emitted when a gamma ray from a distant source strikes a molecule in Earth's atmosphere and starts a charged-particle shower. H.E.S.S. is sensitive to some of the highest energy photons (TeV) crossing the universe. Operating since 2003 in Namibia, H.E.S.S. has searched for dark matter and has discovered over 50 sources emitting high energy radiation including supernova remnants and the centers of galaxies that contain supermassive black holes. Pictured last September, H.E.S.S. telescopes swivel and stare in time-lapse sequences shot in front of our Milky Way Galaxy and the Magellanic Clouds -- as the occasional Earth-orbiting satellite zips by. via NASA https://go.nasa.gov/2LUVtg1

Stars, Meteors, and a Comet in Taurus Stars, Meteors, and a Comet in Taurus

This was an unusual night to look in the direction of the Bull. The constellation Taurus is always well known for hosting two bright star clusters -- the Pleaides, visible on the right, and the comparatively diffuse Hyades, visible on the left. This night last month, however, was atypically the peak of the Geminid meteor shower, and so several meteors were caught shooting through the constellation with parallel trails. More unusually still, Comet Wirtanen was drifting through the constellation, here appearing near the image bottom surrounded by a greenish coma. The comet was near its brightest as it sped past the Earth. The orange star on the upper left is Aldebaran, considered to be the eye of the Bull. Aldebaran is the brightest star in Taurus and the 15th brightest star in the sky. The featured image is a combination of nearly 800 exposures taken from the Spanish village Albanyà. via NASA https://go.nasa.gov/2CVpFEL

A Laser Strike at the Galactic Center A Laser Strike at the Galactic Center

Why are these people shooting a powerful laser into the center of our Galaxy? Fortunately, this is not meant to be the first step in a Galactic war. Rather, astronomers at the Very Large Telescope (VLT) site in Chile are trying to measure the distortions of Earth's ever changing atmosphere. Constant imaging of high-altitude atoms excited by the laser -- which appear like an artificial star -- allow astronomers to instantly measure atmospheric blurring. This information is fed back to a VLT telescope mirror which is then slightly deformed to minimize this blurring. In this case, a VLT was observing our Galaxy's center, and so Earth's atmospheric blurring in that direction was needed. As for inter-galaxy warfare, when viewed from our Galaxy's center, no casualties are expected. In fact, the light from this powerful laser would combine with light from our Sun to together appear only as bright as a faint and distant star. via NASA https://go.nasa.gov/2R8zp7e

Yutu 2 on the Farside Yutu 2 on the Farside

On January 3, the Chinese Chang'e-4 spacecraft made the first successful landing on the Moon's farside. Taken by a camera on board the lander, this image is from the landing site inside Von Karman crater. It shows the desksized, six-wheeled Yutu 2 (Jade Rabbit 2) rover as it rolled down lander ramps and across the surface near local sunrise and the start of the two week long lunar day. Ripe for exploration, Von Karman crater itself is 186 kilometers in diameter. It lies within the Moon's old and deep South Pole-Aitken impact basin with some of the most ancient and least understood lunar terrains. To bridge communications from the normally hidden hemisphere of the Moon, China launched a relay satellite, Queqiao, in May of 2018 in to an orbit beyond the lunar farside. via NASA https://go.nasa.gov/2QlqLgA

Ultima Thule is the most distant world explored by a spacecraft from Earth. In the dim light 6.5 billion kilometers from the Sun, the New Horizons spacecraft captured these two frames 38 minutes apart as it sped toward the Kuiper belt world on January 1 at 51,000 kilometers per hour. A contact binary, the two lobes of Ultima Thule rotate together once every 15 hours or so. Shown as a blinking gif, the rotation between the frames produces a tantalizing 3D perspective of the most primitive world ever seen. Dubbed separately by the science team Ultima and Thule, the larger lobe Ultima, is about 19 kilometers in diameter. Smaller Thule is 14 kilometers across. via NASA https://go.nasa.gov/2R6JMIF

Ultima and Thule Ultima and Thule

On January 1 New Horizons encountered the Kuiper Belt object nicknamed Ultima Thule. Some 6.5 billion kilometers from the Sun, Ultima Thule is the most distant world ever explored by a spacecraft from Earth. This historic image, the highest resolution image released so far, was made at a range of about 28,000 kilometers only 30 minutes before the New Horizons closest approach. Likely the result of a gentle collision shortly after the birth of the Solar System, Ultima Thule is revealed to be a contact binary, two connected sphere-like shapes held in contact by mutual gravity. Dubbed separately by the science team Ultima and Thule, the larger lobe Ultima is about 19 kilometers in diameter. Smaller Thule is 14 kilometers across. via NASA https://go.nasa.gov/2TjLMdk

The Orion Nebula in Infrared from WISE The Orion Nebula in Infrared from WISE

The Great Nebula in Orion is an intriguing place. Visible to the unaided eye, it appears as a small fuzzy patch in the constellation of Orion. But this image, an illusory-color four-panel mosaic taken in different bands of infrared light with the Earth orbiting WISE observatory, shows the Orion Nebula to be a bustling neighborhood of recently formed stars, hot gas, and dark dust. The power behind much of the Orion Nebula (M42) is the stars of the Trapezium star cluster, seen near the center of the featured image. The orange glow surrounding the bright stars pictured here is their own starlight reflected by intricate dust filaments that cover much of the region. The current Orion Nebula cloud complex, which includes the Horsehead Nebula, will slowly disperse over the next 100,000 years. via NASA https://go.nasa.gov/2QdYuII

The Sombrero Galaxy in Infrared The Sombrero Galaxy in Infrared

This floating ring is the size of a galaxy. In fact, it is a galaxy -- or at least part of one: the photogenic Sombrero Galaxy, one of the largest galaxies in the nearby Virgo Cluster of Galaxies. The dark band of dust that obscures the mid-section of the Sombrero Galaxy in optical light actually glows brightly in infrared light. The featured image, digitally sharpened, shows the infrared glow, recently recorded by the orbiting Spitzer Space Telescope, superposed in false-color on an existing image taken by NASA's Hubble Space Telescope in optical light. The Sombrero Galaxy, also known as M104, spans about 50,000 light years across and lies 28 million light years away. M104 can be seen with a small telescope in the direction of the constellation Virgo. via NASA https://go.nasa.gov/2SpV5Zm