Meteor Misses Galaxy Meteor Misses Galaxy

The galaxy was never in danger. For one thing, the Triangulum galaxy (M33), pictured, is much bigger than the tiny grain of rock at the head of the meteor. For another, the galaxy is much farther away -- in this instance 3 million light years as opposed to only about 0.0003 light seconds. Even so, the meteor's path took it angularly below the galaxy. Also the wind high in Earth's atmosphere blew the meteor's glowing evaporative molecule train away from the galaxy, in angular projection. Still, the astrophotographer was quite lucky to capture both a meteor and a galaxy in a single exposure -- which was subsequently added to two other images of M33 to bring up the spiral galaxy's colors. At the end, the meteor was gone in a second, but the galaxy will last billions of years. via NASA https://go.nasa.gov/2vvnm6J

N11: Star Clouds of the LMC N11: Star Clouds of the LMC

Massive stars, abrasive winds, mountains of dust, and energetic light sculpt one of the largest and most picturesque regions of star formation in the Local Group of Galaxies. Known as N11, the region is visible on the upper right of many images of its home galaxy, the Milky Way neighbor known as the Large Magellanic Clouds (LMC). The featured image was taken for scientific purposes by the Hubble Space Telescope and reprocessed for artistry by an amateur to win a Hubble's Hidden Treasures competition. Although the section imaged above is known as NGC 1763, the entire N11 emission nebula is second in LMC size only to the Tarantula Nebula. Compact globules of dark dust housing emerging young stars are also visible around the image. A new study of variable stars in the LMC with Hubble has helped to recalibrate the distance scale of the observable universe, but resulted in a slightly different scale than found using the pervasive cosmic microwave background. via NASA https://go.nasa.gov/2PBumZ8

The Galaxy, the Jet and the Black Hole The Galaxy, the Jet and the Black Hole

Bright elliptical galaxy Messier 87 (M87) is home to the supermassive black hole captured 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 the large galaxy 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 right is approaching and close to our line of sight. Opposite, the shock created by the otherwise unseen receding jet lights up a fainter arc of material. Inset at bottom right, the historic black hole image is shown in context, at the center of giant galaxy and relativistic jets. Completely unresolved in the Spitzer image, the supermassive black hole surrounded by infalling material is the source of the enormous energy driving the relativistic jets from the center of active galaxy M87. via NASA https://go.nasa.gov/2GGntln

Southern Cross to Eta Carinae Southern Cross to Eta Carinae

Tracking along the southern Milky Way this beautiful celestial mosaic was recorded under dark Brazilian skies. Spanning some 20 degrees it actually starts with the dark expanse of the Coalsack nebula at the lower left, tucked under an arm of the Southern Cross. That compact constellation is topped by bright yellowish Gamma Crucis, a cool giant star a mere 88 light-years distant. A line from Gamma Crucis through the blue star at the bottom of the cross, Alpha Crucis, points toward the South Celestial Pole. Follow the Milky Way to the right and your gaze will sweep across IC 2948, popularly known as the Running Chicken nebula, before it reaches Eta Carinae and the Carina Nebula near the right edge of the frame. About 200 light-years across, the Carina Nebula is a star forming region much larger than the more northerly stellar nursery the Orion Nebula. The Carina Nebula lies around 7,500 light-years from Earth along the plane of the Milky Way. via NASA https://go.nasa.gov/2PvFLd5

Mars Methane Mystery Deepens Mars Methane Mystery Deepens

The methane mystery on Mars just got stranger. New results from ESA and Roscosmos' ExoMars Trace Gas Orbiter, has unexpectedly not detected methane in the atmosphere of Mars. This result follows the 2013 detection of methane by NASA's Curiosity rover, a result seemingly confirmed by ESA's orbiting Mars Express the next day. The issue is so interesting because life is a major producer of methane on Earth, leading to intriguing speculation that some sort of life -- possibly microbial life -- is creating methane beneath the surface of Mars. Non-biological sources of methane are also possible. Pictured is a visualization of the first claimed methane plume over Mars as detected from Earth in 2003. The new non-detection of methane by the ExoMars Orbiter could mean that Mars has some unexpected way of destroying methane, or that only some parts of Mars release methane -- and possibly only at certain times. As the mystery has now deepened, humanity's scrutiny of our neighboring planet's atmosphere will deepen as well. via NASA https://go.nasa.gov/2GsivZi

The Leo Trio The Leo Trio

This group is popular in the northern spring. Famous as the Leo Triplet, the three magnificent galaxies gather in one field of view. Crowd pleasers when imaged with even modest telescopes, they can be introduced individually as NGC 3628 (left), M66 (bottom right), and M65 (top). All three are large spiral galaxies but they tend to look dissimilar because their galactic disks are tilted at different angles to our line of sight. NGC 3628, also known as the Hamburger Galaxy, is temptingly seen edge-on, with obscuring dust lanes cutting across its puffy galactic plane. The disks of M66 and M65 are both inclined enough to show off their spiral structure. Gravitational interactions between galaxies in the group have left telltale signs, including the tidal tails and warped, inflated disk of NGC 3628 and the drawn out spiral arms of M66. This gorgeous view of the region spans almost two degrees (four full moons) on the sky. The field covers about a million light-years at the trio's estimated distance of 30 million light-years. Of course the spiky foreground stars lie within our own Milky Way. via NASA https://go.nasa.gov/2IsWf4W

Messier 81 Messier 81

One of the brightest galaxies in planet Earth's sky is similar in size to our Milky Way Galaxy: big, beautiful Messier 81. Also known as NGC 3031 or Bode's galaxy for its 18th century discoverer, this grand spiral can be found toward the northern constellation of Ursa Major, the Great Bear. The detailed telescopic view reveals M81's bright yellow nucleus, blue spiral arms, pink starforming regions, and sweeping cosmic dust lanes. Some dust lanes actually run through the galactic disk (left of center), contrary to other prominent spiral features though. The errant dust lanes may be the lingering result of a close encounter between M81 and its smaller companion galaxy, M82. Scrutiny of variable stars in M81 has yielded one of the best determined distances for an external galaxy -- 11.8 million light-years. via NASA https://go.nasa.gov/2Gtu5V9

In the Vicinity of the Cone Nebula In the Vicinity of the Cone Nebula

Strange shapes and textures can be found in neighborhood of the Cone Nebula. The unusual shapes originate from fine interstellar dust reacting in complex ways with the energetic light and hot gas being expelled by the young stars. The brightest star on the right of the featured picture is S Mon, while the region just below it has been nicknamed the Fox Fur Nebula for its color and structure. The blue glow directly surrounding S Mon results from reflection, where neighboring dust reflects light from the bright star. The red glow that encompasses the whole region results not only from dust reflection but also emission from hydrogen gas ionized by starlight. S Mon is part of a young open cluster of stars named NGC 2264, located about 2500 light years away toward the constellation of the Unicorn (Monoceros). Even though it points right at S Mon, details of the origin of the mysterious geometric Cone Nebula, visible on the far left, remain a mystery. via NASA https://go.nasa.gov/2KKH0Gq

Simulation: Two Black Holes Merge Simulation: Two Black Holes Merge

Sit back and watch two black holes merge. Inspired by the first direct detection of gravitational waves in 2015, this simulation video 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 outside the Einstein rings even after the black holes have merged. Dubbed GW150914, the gravitational waves detected by LIGO are consistent with the merger of 36 and 31 solar mass black holes at a distance of 1.3 billion light-years. The final, single black hole has 63 times the mass of the Sun, with the remaining 3 solar masses converted into energy in gravitational waves. Since then the LIGO and VIRGO gravitational wave observatories have reported several more detections of merging massive systems, while last week the Event Horizon Telescope reported the first horizon-scale image of a black hole. via NASA https://go.nasa.gov/2ZcnBkH

Rigil Kentaurus and Sandqvist 169 Rigil Kentaurus and Sandqvist 169

Rigil Kentaurus is the bright star near the top of this broad southern skyscape. Of course it's probably better known as Alpha Centauri, nearest star system to the Sun. Below it sprawls a dark nebula complex. The obscuring interstellar dust clouds include Sandqvist catalog clouds 169 and 172 in silhouette against the rich starfields along the southern Milky Way. Rigil Kent is a mere 4.37 light-years away, but the dusty dark nebulae lie at the edge of the starforming Circinus-West molecular cloud about 2,500 light-years distant. The wide-field of view spans over 12 degrees (24 full moons) across southern skies. via NASA https://go.nasa.gov/2DcAcei

A Cosmic Rose: The Rosette Nebula in Monoceros A Cosmic Rose: The Rosette Nebula in Monoceros

The Rosette Nebula, NGC 2237, is not the only cosmic cloud of gas and dust to evoke the imagery of flowers, but it is the most famous. At the edge of a large molecular cloud in Monoceros some 5,000 light years away, the petals of this cosmic rose are actually a stellar nursery. The lovely, symmetric shape is sculpted by the winds and radiation from its central cluster of hot young, O-type stars. Stars in the energetic cluster, cataloged as NGC 2244, are only a few million years young, while the central cavity in the Rosette Nebula, is about 50 light-years in diameter. The nebula can be seen with a small telescope toward the constellation of Monoceros, the Unicorn. This natural appearing telescopic portrait of the Rosette Nebula was made using broadband and narrowband filters, because sometimes roses aren't red. via NASA https://go.nasa.gov/2IdX5SR

First Horizon Scale Image of a Black Hole First Horizon Scale Image of a Black Hole

What does a black hole look like? To find out, radio telescopes from around the Earth coordinated observations of black holes with the largest known event horizons on the sky. Alone, black holes are just black, but these monster attractors are known to be surrounded by glowing gas. The first image was released yesterday and resolved the area around the black hole at the center of galaxy M87 on a scale below that expected for its event horizon. Pictured, the dark central region is not the event horizon, but rather the black hole's shadow -- the central region of emitting gas darkened by the central black hole's gravity. The size and shape of the shadow is determined by bright gas near the event horizon, by strong gravitational lensing deflections, and by the black hole's spin. In resolving this black hole's shadow, the Event Horizon Telescope (ETH) bolstered evidence that Einstein's gravity works even in extreme regions, and gave clear evidence that M87 has a central spinning black hole of about 6 billion solar masses. The EHT is not done -- future observations will be geared toward even higher resolution, better tracking of variability, and exploring the immediate vicinity of the black hole in the center of our Milky Way Galaxy. via NASA https://go.nasa.gov/2P61LuD

Martian Moon Phobos Crosses the Sun Martian Moon Phobos Crosses the Sun

What's that passing in front of the Sun? It looks like a moon, but it can't be Earth's Moon, because it isn't round. It's the Martian moon Phobos. The featured video was taken from the surface of Mars late last month by the Curiosity rover. Phobos, at 11.5 kilometers across, is 150 times smaller than Luna (our moon) in diameter, but also 50 times closer to its parent planet. In fact, Phobos is so close to Mars that it is expected to break up and crash into Mars within the next 50 million years. In the near term, the low orbit of Phobos results in more rapid solar eclipses than seen from Earth. The featured video has been sped up -- the actual transit took about 35 seconds. A similar video was taken of Mars' smaller and most distant moon Diemos transiting the Sun. The videographer -- the robotic rover Curiosity -- continues to explore Gale crater, most recently an area with stunning vistas and unusual rocks dubbed Glen Torridon. via NASA https://go.nasa.gov/2UJ3Odj

Moon Occults Saturn Moon Occults Saturn

Sometimes Saturn disappears. It doesn't really go away, though, it just disappears from view when our Moon moves in front. Such a Saturnian eclipse was visible along a small swath of Earth -- from Brazil to Sri Lanka -- near the end of last month. The featured color image is a digital fusion of the clearest images captured by successive videos of the event taken in red, green, and blue, and taken separately for Saturn and the comparative bright Moon. The exposures were taken from South Africa just before occultation -- and also just before sunrise. When Saturn re-appeared on the other side of the Moon almost two hours later, the Sun had risen. This year, eclipses of Saturn by the Moon occur almost monthly, but, unfortunately, are visible only to those with the right location and with clear and dark skies. via NASA https://go.nasa.gov/2KkdqaA

A Scorpius Sky Spectacular A Scorpius Sky Spectacular

If Scorpius looked this good to the unaided eye, humans might remember it better. Scorpius more typically appears as a few bright stars in a well-known but rarely pointed out zodiacal constellation. To get a spectacular image like this, though, one needs a good camera, color filters, and a digital image processor. To bring out detail, the featured image not only involved long duration exposures taken in several colors, but one exposure in a very specific red color emitted by hydrogen. The resulting image shows many breathtaking features. Vertically across the image left is part of the plane of our Milky Way Galaxy. Visible there are vast clouds of bright stars and long filaments of dark dust. Jutting out diagonally from the Milky Way in the image center are dark dust bands known as the Dark River. This river connects to several bright stars on the right that are part of Scorpius' head and claws, and include the bright star Antares. Above and right of Antares is an even brighter planet: Jupiter. Numerous red emission nebulas and blue reflection nebulas are visible throughout the image. Scorpius appears prominently in southern skies after sunset during the middle of the year. via NASA https://go.nasa.gov/2UojZ0v

ISS from Wallasey ISS from Wallasey

After sunset on March 28, the International Space Station climbed above the western horizon, as seen from Wallasey, England at the mouth of the River Mersey. Still glinting in the sunlight some 400 kilometers above planet Earth, the fast moving ISS was followed by hand with a small backyard telescope and high frame rate digital camera. A total of 2500 frames were recorded during the 7 minute long visible ISS passage and 100 of them captured images of the space station. These are the four best frames showing remarkable details of the ISS in low Earth orbit. Near the peak of its track, about 60 degrees above the horizon, the ISS was brighter than the brightest star in the sky and as close as 468 kilometers to the Wallasey backyard. via NASA https://go.nasa.gov/2G3PHaz

Messier 2 Messier 2

After the Crab Nebula, M1, this giant star cluster is the second entry in 18th century astronomer Charles Messier's famous list of things with are not comets. M2 is one of the largest globular star clusters now known to roam the halo of our Milky Way galaxy. Though Messier originally described it a nebula without stars, this stunning Hubble image resolves stars across the central 40 light-years of M2. Its population of stars numbers close to 150,000, concentrated within a total diameter of around 175 light-years. About 55,000 light-years distant toward the constellation Aquarius, this ancient denizen of the Milky Way, also known as NGC 7089, is 13 billion years old. via NASA https://ift.tt/2UfjcPi

Wisps Surrounding the Horsehead Nebula Wisps Surrounding the Horsehead Nebula

The famous Horsehead Nebula in Orion is not alone. A deep exposure shows that the dark familiar shaped indentation, visible just below center, is part of a vast complex of absorbing dust and glowing gas. To bring out details of the Horsehead's pasture, an amateur astronomer used a backyard telescope in Austria to accumulate and artistically combine 7.5 hours of images in the light of Hydrogen (red), Oxygen (green), and Sulfur (blue). The resulting spectacular picture details an intricate tapestry of gaseous wisps and dust-laden filaments that were created and sculpted over eons by stellar winds and ancient supernovas. The Flame Nebula is visible just to the left of the Horsehead, while the bright star on the upper left is Alnilam, the central star in Orion's Belt. The Horsehead Nebula lies 1,500 light years distant towards the constellation of Orion. via NASA https://ift.tt/2FTCErX

Astronaut Kicks Lunar Field Goal Astronaut Kicks Lunar Field Goal

Score three points for NASA. With time running out late in Apollo 15's mission to the Moon in 1971, Astronaut David Scott prepared to split the uprights and bring about yet another dramatic end-of-the-mission victory for NASA. Scott used a special lunar football designed for the rugged games held on the Moon. R1-D1, a predecessor to R2-D2, cheered from the sideline. Happy April Fools' Day from the folks at APOD. In reality, Astronaut Scott placed a drill that measured how temperature changed with lunar depth. The foreground device actually detected high-energy particles that escaped from the Sun. via NASA https://ift.tt/2U9c8Ut