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By Sharon LaFraniere and Noah Weiland from NYT Science https://ift.tt/Iwr0k4NvE

What will the Moon phase be on your birthday this year? It is hard to predict because the 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 and altitude data taken by NASA's Moon-orbiting Lunar Reconnaissance Orbiter to show all 12 lunations that appear this year, 2022 -- as seen from Earth's northern ( southern ) hemisphere. 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 ...

By William J. Broad from NYT Science https://ift.tt/ZNibTug5j

The Great Carina Nebula is home to strange stars and iconic nebulas. Named for its home constellation , the huge star-forming region is larger and brighter than the Great Orion Nebula but less well known because it is so far south -- and because so much of humanity lives so far north . The featured image shows in great detail the northern-most part of the Carina Nebula . Visible nebulas include the semi-circular filaments surrounding the active star Wolf-Rayet 23 (WR23) on the far left. Just left of center is the Gabriela Mistral Nebula consisting of an emission nebula of glowing gas (IC 2599) surrounding the small open cluster of stars ( NGC 3324 ). Above the image center is the larger star cluster NGC 3293 , while to its right is the relatively faint emission nebula designated Loden 153. The most famous occupant of the Carina Nebula , however, is not shown. Off the image to the lower right is the bright, erratic, and doomed star star known as Eta Carinae -- a star once o...

By Annie Roth from NYT Science https://ift.tt/1aBcOpNPm

How can gas float above the Sun? Twisted magnetic fields arching from the solar surface can trap ionized gas, suspending it in huge looping structures. These majestic plasma arches are seen as prominence s above the solar limb. In 1999, this dramatic and detailed image was recorded by the Extreme ultraviolet Image Telescope (EIT) on board the space-based SOHO observatory in the light emitted by ionized Helium . It shows hot plasma escaping into space as a fiery prominence breaks free from magnetic confinement a hundred thousand kilometers above the Sun. These awesome events bear watching as they can affect communications and power systems over 100 million kilometers away on planet Earth . In late 2020 our Sun passed the solar minimum of its 11-year cycle and is now showing increased surface activity . from NASA https://ift.tt/UOD9hFRjx

Named for the southern constellation toward which most of its galaxies can be found, the Fornax Cluster is one of the closest clusters of galaxies. About 62 million light-years away, it is almost 20 times more distant than our neighboring Andromeda Galaxy , and only about 10 percent farther than the better known and more populated Virgo Galaxy Cluster . Seen across this two degree wide field-of-view, almost every yellowish splotch on the image is an elliptical galaxy in the Fornax cluster . Elliptical galaxies NGC 1399 and NGC 1404 are the dominant, bright cluster members toward the upper left (but not the spiky foreground stars). A standout barred spiral galaxy NGC 1365 is visible on the lower right as a prominent Fornax cluster member. from NASA https://go.nasa.gov/3KR80ip

By Dennis Overbye from NYT Science https://ift.tt/3IKGMIi

The Mare Orientale , Latin for Eastern Sea, is one of the most striking large scale lunar features. The youngest of the large lunar impact basins it's very difficult to see from an earthbound perspective . Still, taken during a period of favorable tilt, or libration of the lunar nearside, the Eastern Sea can be found near top center in this sharp telescopic view, extremely foreshortened along the Moon's western edge . Formed by the impact of an asteroid over 3 billion years ago and nearly 1000 kilometers across, the impact basin's concentric circular features, ripples in the lunar crust, are a little easier to spot in spacecraft images of the Moon, though. So why is the Eastern Sea at the Moon's western edge? The Mare Orientale lunar feature was named before 1961. That's when the convention labeling east and west on lunar maps was reversed. from NASA https://ift.tt/33QOJND

South of the large star-forming region known as the Orion Nebula, lies bright blue reflection nebula NGC 1999 . At the edge of the Orion molecular cloud complex some 1,500 light-years distant, NGC 1999's illumination is provided by the embedded variable star V380 Orionis. The nebula is marked with a dark sideways T-shape at center right in this telescopic vista that spans about two full moons on the sky. Its dark shape was once assumed to be an obscuring dust cloud seen in silhouette. But infrared data suggest the shape is likely a hole blown through the nebula itself by energetic young stars. In fact, this region abounds with energetic young stars producing jets and outflows with luminous shock waves. Cataloged as Herbig-Haro (HH) objects, named for astronomers George Herbig and Guillermo Haro, the shocks have intense reddish hues. HH1 and HH2 are just below and right of NGC 1999. HH222, also known as the Waterfall nebula , looks like a red gash near top right in the frame. T...

Why is the sky near Antares and Rho Ophiuchi so dusty yet colorful? The colors result from a mixture of objects and processes. Fine dust -- illuminated from the front by starlight -- produces blue reflection nebulae . Gaseous clouds whose atoms are excited by ultraviolet starlight produce reddish emission nebulae . Backlit dust clouds block starlight and so appear dark . Antares , a red supergiant and one of the brighter stars in the night sky , lights up the yellow-red clouds on the lower right of the featured image . The Rho Ophiuchi star system lies at the center of the blue reflection nebula on the top left. The distant globular cluster of stars M4 is visible above and to the right of Antares. These star clouds are even more colorful than humans can see, emitting light across the electromagnetic spectrum . from NASA https://ift.tt/3nXUCPI

By Carl Zimmer from NYT Science https://ift.tt/3rLq6K3

Which direction is this comet heading? Judging by the tail, one might imagine that Comet Leonard is traveling towards the bottom right, but a full 3D analysis shows it traveling almost directly away from the camera. With this perspective, the dust tail is trailed towards the camera and can only be seen as a short yellow-white glow near the head of the comet. The bluish ion tail , however, is made up of escaping ions that are forced directly away from the Sun by the solar wind -- but channeled along the Sun's magnetic field lines. The Sun's magnetic field is quite complex, however, and occasionally solar magnetic reconnection will break the ion tail into knots that are pushed away from the Sun. One such knot is visible in the featured one-hour time-lapse video captured in late December from Thailand . Comet Leonard is now fading as it heads out of our Solar System . from NASA https://ift.tt/345Aq7k

By Joey Roulette from NYT Science https://ift.tt/3Ar0iXq

By starlight this eerie visage shines in the dark, a crooked profile evoking its popular name, the Witch Head Nebula . In fact, this entrancing telescopic portrait gives the impression that the witch has fixed her gaze on Orion's bright supergiant star Rigel . More formally known as IC 2118 , the Witch Head Nebula spans about 50 light-year s and is composed of interstellar dust grains reflecting Rigel's starlight. The blue color of the Witch Head Nebula and of the dust surrounding Rigel is caused not only by Rigel 's intense blue starlight but because the dust grains scatter blue light more efficiently than red. The same physical process causes Earth's daytime sky to appear blue , although the scatterers in Earth's atmosphere are molecules of nitrogen and oxygen . Rigel, the Witch Head Nebula , and gas and dust that surrounds them lie about 800 light-years away. from NASA https://ift.tt/3AuvO7c

Seen from ice moon Tethys , rings and shadows would display fantastic views of the Saturnian system. Haven't dropped in on Tethys lately? Then this gorgeous ringscape from the Cassini spacecraft will have to do for now. Caught in sunlight just below and left of picture center in 2005, Tethys itself is about 1,000 kilometers in diameter and orbits not quite five saturn-radii from the center of the gas giant planet. At that distance (around 300,000 kilometers) it is well outside Saturn's main bright rings , but Tethys is still one of five major moons that find themselves within the boundaries of the faint and tenuous outer E ring . Discovered in the 1980s, two very small moons Telesto and Calypso are locked in stable along Tethys' orbit. Telesto precedes and Calypso follows Tethys as the trio circles Saturn . from NASA https://ift.tt/3fMPlpJ

On Monday, January's Full Moon rose as the Sun set. Spotted near the eastern horizon, its warm hues are seen in this photo taken near Cagliari, capital city of the Italian island of Sardinia. Of course the familiar patterns of light and dark across the Moon's nearside are created by bright rugged highlands and dark smooth lunar maria. Traditionally the patterns are seen as pareidolia , giving the visual illusion of a human face like the Man in the Moon , or familiar animal like the Moon rabbit . But for a moment the swarming murmuration , also known as a flock of starlings, frozen in the snapshot's field of view lends another pareidolic element to the scene. Some see the graceful figure of a dancer enchanted by moonlight . from NASA https://ift.tt/3FQqLig

By Annie Roth from NYT Science https://ift.tt/3IqaQJ8

Laser guide stars and adaptive optics sharpened this stunning ground-based image of stellar jets from the Gemini South Observatory , Chilean Andes, planet Earth. These twin outflows of MHO 2147 are from a young star in formation . It lies toward the central Milky Way and the boundary of the constellations Sagittarius and Ophiuchus at an estimated distance of some 10,000 light-years. At center, the star itself is obscured by a dense region of cold dust. But the infrared image still traces the sinuous jets across a frame that would span about 5 light-years at the system's estimated distance. Driven outward by the young rotating star, the apparent wandering direction of the jets is likely due to precession. Part of a multiple star system, the young star's rotational axis would slowly precess or wobble like a top under the gravitation influence of its nearby companions. from NASA https://ift.tt/3tIP8fl

Hot, young stars and cosmic pillars of gas and dust seem to crowd into NGC 7822. At the edge of a giant molecular cloud toward the northern constellation Cepheus, the glowing star forming region lies about 3,000 light-years away. Within the nebula, bright edges and dark shapes stand out in this colorful telescopic skyscape . The image includes data from narrowband filters, mapping emission from atomic oxygen, hydrogen, and sulfur into blue, green, and red hues. The emission line and color combination has become well-known as the Hubble palette . The atomic emission is powered by energetic radiation from the central hot stars. Their powerful winds and radiation sculpt and erode the denser pillar shapes and clear out a characteristic cavity light-years across the center of the natal cloud. Stars could still be forming inside the pillars by gravitational collapse but as the pillars are eroded away, any forming stars will ultimately be cutoff from their reservoir of star stuff . This...

The most distant object easily visible to the unaided eye is M31 , the great Andromeda Galaxy . Even at some two and a half million light-year s distant, this immense spiral galaxy -- spanning over 200,000 light years -- is visible, although as a faint, nebulous cloud in the constellation Andromeda . In contrast, a bright yellow nucleus, dark winding dust lanes , and expansive spiral arms dotted with blue star cluster s and red nebulae , are recorded in this stunning telescopic image which combines data from orbiting Hubble with ground-based images from Subaru and Mayall . In only about 5 billion years, the Andromeda galaxy may be even easier to see -- as it will likely span the entire night sky -- just before it merges with our Milky Way Galaxy . from NASA https://ift.tt/3fCygPf

This is a sky filled with glowing icons. On the far left is the familiar constellation of Orion , divided by its iconic three-aligned belt stars and featuring the famous Orion Nebula , both partly encircled by Barnard's Loop . Just left of center in the featured image is the brightest star in the night: Sirius . Arching across the image center is the central band of our Milky Way Galaxy . On the far right, near the top, are the two brightest satellite galaxies of the Milky Way: the Large Magellanic Cloud (LMC), and the Small Magellanic Cloud (SMC). Also on the far right -- just above the cloudy horizon -- is the constellation of Crux , complete with the four stars that make the iconic Southern Cross . The featured image is a composite of 18 consecutive exposures taken by the same camera and from the same location in eastern Australia during the last days of last year. In the foreground, picturesque basalt columns of the Bombo Quarry part to reveal the vast Pacific Ocean . ...

Sometimes the dark dust of interstellar space has an angular elegance. Such is the case toward the far-south constellation of Chamaeleon . Normally too faint to see , dark dust is best known for blocking visible light from stars and galaxies behind it. In this four-hour exposure , however, the dust is seen mostly in light of its own, with its strong red and near- infrared colors giving creating a brown hue. Contrastingly blue, the bright star Beta Chamaeleontis is visible just to the right of center, with the dust that surrounds it preferentially reflecting blue light from its primarily blue-white color. All of the pictured stars and dust occur in our own Milky Way Galaxy with -- but one notable exception : the white spot just below Beta Chamaeleontis is the galaxy IC 3104 which lies far in the distance. Interstellar dust is mostly created in the cool atmospheres of giant stars and dispersed into space by stellar light, stellar winds , and stellar explosions such as supernovas...

What type of cloud is that? This retreating cumulonimbus cloud , more commonly called a thundercloud, is somewhat unusual as it contains the unusual bumpiness of a mammatus cloud on the near end, while simultaneously producing falling rain on the far end. Taken in mid-2013 in southern Alberta , Canada , the cloud is moving to the east, into the distance, as the sun sets in the west, behind the camera. In the featured image , graphic sunset colors cross the sky to give the already photogenic cloud striking orange and pink hues. A darkening blue sky covers the background. Further in the distance, a rising , waxing , gibbous moon is visible on the far right. from NASA https://ift.tt/3FtRQrn

Looping through the Jovian system in the late 1990s, the Galileo spacecraft recorded stunning views of Europa and uncovered evidence that the moon's icy surface likely hides a deep, global ocean. Galileo's Europa image data has been remastered here , with improved calibrations to produce a color image approximating what the human eye might see. Europa's long curving fractures hint at the subsurface liquid water . The tidal flexing the large moon experiences in its elliptical orbit around Jupiter supplies the energy to keep the ocean liquid. But more tantalizing is the possibility that even in the absence of sunlight that process could also supply the energy to support life, making Europa one of the best places to look for life beyond Earth. What kind of life could thrive in a deep, dark, subsurface ocean? Consider planet Earth's own extreme shrimp . from NASA https://ift.tt/3rjpuey

An island universe of billions of stars, NGC 1566 lies about 60 million light-years away in the southern constellation Dorado . Popularly known as the Spanish Dancer galaxy, it's seen face-on from our Milky Way perspective . A gorgeous grand design spiral, this galaxy's two graceful spiral arms span over 100,000 light-years, traced by bright blue star clusters , pinkish starforming regions, and swirling cosmic dust lanes. NGC 1566's flaring center makes the spiral one of the closest and brightest Seyfert galaxies . It likely houses a central supermassive black hole wreaking havoc on surrounding stars, gas, and dust . In this sharp southern galaxy portrait, the spiky stars lie well within the Milky Way. from NASA https://ift.tt/3zXR5FN

By Sabrina Imbler from NYT Science https://ift.tt/33wiySQ

It's easy to get lost following the intricate, looping, twisting filaments in this detailed image of supernova remnant Simeis 147. Also cataloged as Sharpless 2-240 it goes by the popular nickname, the Spaghetti Nebula. Seen toward the boundary of the constellations Taurus and Auriga, it covers nearly 3 degrees or 6 full moons on the sky. That's about 150 light-years at the stellar debris cloud's estimated distance of 3,000 light-years. This composite includes image data taken through narrow-band filters where reddish emission from ionized hydrogen atoms and doubly ionized oxygen atoms in faint blue-green hues trace the shocked, glowing gas . The supernova remnant has an estimated age of about 40,000 years, meaning light from the massive stellar explosion first reached Earth 40,000 years ago. But the expanding remnant is not the only aftermath. The cosmic catastrophe also left behind a spinning neutron star or pulsar, all that remains of the original star's core. ...

What does Comet Leonard look like up close? Although we can't go there, imaging the comet's coma and inner tails through a small telescope gives us a good idea. As the name implies, the ion tail is made of ionized gas -- gas energized by ultraviolet light from the Sun and pushed outward by the solar wind . The solar wind is quite structured and sculpted by the Sun's complex and ever changing magnetic field . The effect of the variable solar wind combined with different gas jets venting from the comet's nucleus accounts for the tail's complex structure. Following the wind, structure in Comet Leonard's tail can be seen to move outward from the Sun even alter its wavy appearance over time. The blue color of the ion tail is dominated by recombining carbon monoxide molecules, while the green color of the coma surrounding the head of the comet is created mostly by a slight amount of recombining diatomic carbon molecules. Diatomic carbon is destroyed by sunligh...

You may have seen Orion's belt before -- but not like this. The three bright stars across this image are, from left to right, Mintaka , Alnilam , and Alnitak : the iconic belt stars of Orion . The rest of the stars in the frame have been digitally removed to highlight the surrounding clouds of glowing gas and dark dust. Some of these clouds have intriguing shapes, including the Horsehead and Flame Nebula s, both near Alnitak on the lower right. This deep image , taken last month from the Marathon Skypark and Observatory in Marathon , Texas , USA , spans about 5 degrees, required about 20 hours of exposure, and was processed to reveal the gas and dust that we would really see if we were much closer. The famous Orion Nebula is off to the upper right of this colorful field. The entire region lies only about 1,500 light-years distant and so is one of the closest and best studied star formation nurseries known. from NASA https://ift.tt/33bcpvw

Why does Comet Leonard's tail wag? The featured time-lapse video shows the ion tail of Comet C/2021 A1 (Leonard) as it changed over ten days early last month. The video was taken by NASA's Solar Terrestrial Relations Observatory -Ahead (STEREO-A) spacecraft that co-orbits the Sun at roughly the same distance as the Earth. Each image in this 29-degree field was subtracted from following image to create frames that highlight differences. The video clearly shows Comet Leonard's long ion tail extending, wagging , and otherwise being blown around by the solar wind -- a stream of fast-moving ion s that stream out from the Sun . Since the video was taken, Comet Leonard continued plunging toward the Sun, reached its closest approach to the Sun between the orbits of Mercury and Venus, survived this closest approach without breaking apart , and is now fading as heads out of our Solar System . from NASA https://ift.tt/3f8ESoc

What will become of Jupiter's Great Red Spot? Gas giant Jupiter is the solar system's largest world with about 320 times the mass of planet Earth . Jupiter is home to one of the largest and longest lasting storm systems known, the Great Red Spot (GRS), visible to the left. The GRS is so large it could swallow Earth, although it has been shrinking. Comparison with historical notes indicate that the storm spans only about one third of the exposed surface area it had 150 years ago. NASA's Outer Planets Atmospheres Legacy (OPAL) program has been monitoring the storm more recently using the Hubble Space Telescope . The featured Hubble OPAL image shows Jupiter as it appeared in 2016, processed in a way that makes red hues appear quite vibrant. Modern GRS data indicate that the storm continues to constrict its surface area, but is also becoming slightly taller , vertically. No one knows the future of the GRS , including the possibility that if the shrinking trend continue...

By Joey Roulette and Dennis Overbye from NYT Science https://ift.tt/3q4d9eC

Named for a forgotten constellation , the Quadrantid Meteor Shower puts on an annual show for planet Earth's northern hemisphere skygazers. The shower's radiant on the sky lies within the old, astronomically obsolete constellation Quadrans Muralis . That location is not far from the Big Dipper, at the boundaries of the modern constellations Bootes and Draco. In fact north star Polaris is just below center in this frame and the Big Dipper asterism (known to some as the Plough ) is above it, with the meteor shower radiant to the right. Pointing back toward the radiant, Quadrantid meteors streak through the night in the panoramic skyscape, a composite of images taken in the hours around the shower's peak on January 4, 2022. Arrayed in the foreground are radio telescopes of the Chinese Spectral Radioheliograph , Mingantu Observing Station, Inner Mongolia, China. A likely source of the dust stream that produces Quadrantid meteors was identified in 2003 as an asteroid . from ...

A male Adelie penguin performed this Ecstatic Vocalization in silhouette during the December 4 solar eclipse , the final eclipse of 2021. Of course his Ecstatic Vocalization is a special display that male penguins use to claim their territory and advertise their condition . This penguin's territory, at Cape Crozier Antarctica, is located in one of the largest Adelie penguin colonies. The colony has been studied by researchers for over 25 years . From there, last December's eclipse was about 80 percent total when seen at its maximum phase as the Moon's shadow crossed planet Earth's southernmost continent . from NASA https://ift.tt/3q4wRH2

That's not a young crescent Moon posing behind cathedral towers after sunset. It's Venus in a crescent phase. About 40 million kilometers away and about 2 percent illuminated by sunlight, it was captured with camera and telephoto lens in this series of exposures as it set in western skies on January 1 from Veszprem, Hungary. The bright celestial beacon was languishing in the evening twilight, its days as the Evening Star coming to a close as 2022 began. But it was also growing larger in apparent size and becoming an ever thinner crescent in telescopic views . Heading toward a (non-judgemental) inferior conjunction , the inner planet will be positioned between Earth and Sun on January 9 and generally lost from view in the solar glare. A crescent Venus will soon reappear though. Rising in the east by mid-month just before the Sun as the brilliant Morning Star . from NASA https://ift.tt/3EYOMDm

Does the Sun always rise in the same direction? No. As the months change, the direction toward the rising Sun changes, too. The featured image shows the direction of sunrise every month during 2021 as seen from the city of Edmonton , Alberta , Canada . The camera in the image is always facing due east, with north toward the left and south toward the right. As shown in an accompanying video , the top image was taken in 2020 December, while the bottom image was captured in 2021 December, making 13 images in total. Although the Sun always rises in the east in general, it rises furthest to the south of east on the December solstice , and furthest north of east on the June solstice . In many countries, the December Solstice is considered an official change in season: for example the first day of winter in the North . Solar heating and stored energy in the Earth's surface and atmosphere are near their lowest during winter, making the winter season the coldest of the year. from N...

What's happened to that moon of Saturn? Nothing -- Saturn's moon Rhea is just partly hidden behind Saturn's rings. In 2010, the robotic Cassini spacecraft then orbiting Saturn took this narrow-angle view looking across the Solar System 's most famous rings . Rings visible in the foreground include the thin F ring on the outside and the much wider A and B rings just interior to it. Although it seems to be hovering over the rings , Saturn's moon Janus is actually far behind them. Janus is one of Saturn's smaller moons and measures only about 180 kilometers across. Farther out from the camera is the heavily cratered Rhea , a much larger moon measuring 1,500 kilometers across. The top of Rhea is visible only through gaps in the rings. 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 . from NASA https://ift.tt/3eLbOD4

By Jonathan O’Callaghan from NYT Science https://ift.tt/3eFBv82

Sometimes falling ice crystals make the atmosphere into a giant lens causing arcs and halos to appear around the Sun or Moon. One Saturday night in 2012 was just such a time near Madrid , Spain , where a winter sky displayed not only a bright Moon but four rare lunar halos. The brightest object, near the top of the featured image , is the Moon. Light from the Moon refracts through tumbling hexagonal ice crystals into a somewhat rare 22-degree halo seen surrounding the Moon. Elongating the 22-degree arc horizontally is a more rare circumscribed halo caused by column ice crystals . Even more rare, some moonlight refracts through more distant tumbling ice crystals to form a (third) rainbow-like arc 46 degrees from the Moon and appearing here just above a picturesque winter landscape. Furthermore, part of a whole 46-degree circular halo is also visible, so that an extremely rare -- especially for the Moon -- quadruple halo was captured. Far in the background is a famous winter sky...

Every Full Moon of 2021 shines in this year-spanning astrophoto project, a composite portrait of the familiar lunar nearside at each brightest lunar phase . Arranged by moonth , the year progresses in stripes beginning at the top. Taken with the same camera and lens the stripes are from Full Moon images all combined at the same pixel scale. The stripes still looked mismatched, but they show that the Full Moon's angular size changes throughout the year depending on its distance from Kolkata, India, planet Earth. The calendar month , a full moon name, distance in kilometers, and angular size is indicated for each stripe. Angular size is given in minutes of arc corresponding to 1/60th of a degree. The largest Full Moon is near a perigee or closest approach in May. The smallest is near an apogee , the most distant Full Moon in December. Of course the full moons of May and November also slid into Earth's shadow during 2021's two lunar eclipses. from NASA https://ift.tt/3FW...

This timelapse gif tracks the James Webb Space Telescope as it streaks across the stars of Orion on its journey to a destination beyond the Moon. Recorded on December 28, 12 consecutive exposures each 10 minutes long were aligned and combined with a subsequent color image of the background stars to create the animation. About 2.5 days after its December 25 launch, JWST cruised past the altitude of the Moon's orbit as it climbed up the gravity ridge from Earth to reach a halo orbit around L2, an Earth-Sun Lagrange point . Lagrange points are convenient locations in space where the combined gravitational attraction of one massive body (Earth) orbiting another massive body (Sun) is in balance with the centripetal force needed to move along with them . So much smaller masses, like spacecraft, will tend to stay there. One of 5 Lagrange points, L2 is about 1.5 million kilometers from Earth directly along the Earth-Sun line. JWST will arrive at L2 on January 23, 29 days after launch. W...

Comet Leonard , brightest comet of 2021, is at the lower left of these two panels captured on December 29 in dark Atacama desert skies. Heading for its perihelion on January 3 Comet Leonard's visible tail has grown. Stacked exposures with a wide angle lens (also displayed in a reversed B/W scheme for contrast), trace the complicated ion tail for an amazing 60 degrees, with bright Jupiter shining near the horizon at lower right. Material vaporizing from Comet Leonard's nucleus , a mass of dust, rock, and ices about 1 kilometer across, has produced the long tail of ionized gas fluorescing in the sunlight. Likely flares on the comet's nucleus and buffeting by magnetic fields and the solar wind in recent weeks have resulted in the tail's irregular pinched and twisted appearance . Still days from its closest approach to the Sun, Comet Leonard's activity should continue. The comet is south of the Solar System's ecliptic plane as it sweeps through the southern con...

What and where are these large ovals? They are rotating storm clouds on Jupiter imaged last month by NASA's Juno spacecraft . In general, higher clouds are lighter in color, and the lightest clouds visible are the relatively small clouds that dot the lower oval. At 50 kilometers across, however, even these light clouds are not small. They are so high up that they cast shadows on the swirling oval below. The featured image has been processed to enhance color and contrast. Large oval s are usually regions of high pressure that span over 1000 kilometers and can last for years. The largest oval on Jupiter is the Great Red Spot (not pictured), which has lasted for at least hundreds of years. Studying cloud dynamics on Jupiter with Juno images enables a better understanding of dangerous typhoons and hurricanes on Earth. from NASA https://ift.tt/3ezhb8d

What's happened to the Sun? Sometimes it looks like the Sun is being viewed through a giant lens . In the featured video, however, there are actually millions of tiny lenses: ice crystals . Water may freeze in the atmosphere into small, flat, six-sided, ice crystals. As these crystals flutter to the ground, much time is spent with their faces flat and parallel to the ground. An observer may find themselves in the same plane as many of the falling ice crystals near sunrise or sunset. During this alignment, each crystal can act like a miniature lens, refracting sunlight into our view and creating phenomena like parhelia , the technical term for sundogs . The featured video was taken in late 2017 on the side of a ski hill at the Vemdalen Ski Resort in central Sweden . Visible in the center is the most direct image of the Sun , while two bright sundogs glow prominently from both the left and the right. Also visible is the bright 22 degree halo -- as well as the rarer and muc...

By Carl Zimmer from NYT Science https://ift.tt/3qv0Cjh

Which one of these two streaks is a comet? Although they both have comet-like features, the lower streak is the only real comet. This lower streak shows the coma and tail of Comet Leonard , a city-sized block of rocky ice that is passing through the inner Solar System as it continues its looping orbit around the Sun. Comet Leonard has recently passed its closest to both the Earth and Venus and will round the Sun next week. The comet, still visible to the unaided eye, has developed a long and changing tail in recent weeks. In contrast, the upper streak is the launch plume of the Ariane V rocket that lifted the James Webb Space Telescope (JWST) off the Earth two days ago. The featured single-exposure image was taken from Thailand , and the foreground spire is atop a pagoda in Doi Inthanon National Park . JWST , NASA's largest and most powerful space telescope so far, will orbit the Sun near the Earth-Sun L2 point and is scheduled to start science observations in the summe...

There's a big new telescope in space. This one, the James Webb Space Telescope (JWST), not only has a mirror over five times larger than Hubble 's in area, but can see better in infrared light. The featured picture shows JWST high above the Earth just after being released by the upper stage of an Ariane V rocket, launched yesterday from French Guiana . Over the next month, JWST will move out near the Sun-Earth L2 point where it will co-orbit the Sun with the Earth. During this time and for the next five months, JWST will unravel its segmented mirror and an array of sophisticated scientific instruments -- and test them. If all goes well, JWST will start examining galaxies across the universe and planets orbiting stars across our Milky Way Galaxy in the summer of 2022. from NASA https://ift.tt/3qsVlZC

By Dennis Overbye and Joey Roulette from NYT Science https://ift.tt/3qsfvTy

The tail of a comet streams across this three degree wide telescopic field of view captured under dark Namibian skies on December 21. In outburst only a few days ago and just reaching naked eye visibility Comet Leonard (C/2021 A1) is this year's brightest comet. Binoculars will make the diffuse comet easier to spot though, close to the western horizon after sunset. Details revealed in the sharp image show the comet's coma with a greenish tinge, and follow the interaction of the comet's ion tail with magnetic fields in the solar wind. After passing closest to Earth on December 12 and Venus on December 18, Comet Leonard is heading toward perihelion, its closest approach to the Sun on January 3rd. Appearing in late December's beautiful evening skies after sunset, Comet Leonard has also become known as 2021's Christmas Comet. from NASA https://ift.tt/3qriJXl