Astronomy picture of the day - 2018 March 31 - Twilight in a Western Sky

Twilight in a Western Sky 
Image Credit & Copyright: Stan Honda

Explanation: A slender crescent Moon and inner planets Venus and Mercury never wander far from the Sun in planet Earth's skies. In the fading evening twilight of March 18, they line up near the western horizon in this atmospheric skyscape. While the celestial scene was enjoyed around the world, this photo captures the trio, with fainter Mercury at the far right, above the crags of Big Bend National Park in southwest Texas. Tonight the Moon will be full though, and rise opposite the Sun. Look for it high in the sky at midnight, near bright star Spica.

Astronomy picture of the day - 2018 March 30 - NGC 247 and Friends

NGC 247 and Friends 
Image Credit & Copyright: CHART32 Team, Processing - Johannes Schedler

Explanation: About 70,000 light-years across, NGC 247 is a spiral galaxy smaller than our Milky Way. Measured to be only 11 million light-years distant it is nearby though. Tilted nearly edge-on as seen from our perspective, it dominates this telescopic field of view toward the southern constellation Cetus. The pronounced void on one side of the galaxy's disk recalls for some its popular name, the Needle's Eye galaxy. Many background galaxies are visible inthis sharp galaxy portrait, including the remarkable string of four galaxies just below and left of NGC 247 known as Burbidge's Chain. Burbidge's Chain galaxies are about 300 million light-years distant. The deep image even reveals that the two leftmost galaxies in the chain are apparently interacting, joined by a faint bridge of material. NGC 247 itself is part of the Sculptor Group of galaxies along with the shiny spiral NGC 253.

Astronomy picture of the day - 2018 March 29 - NGC 2023 in the Horsehead's Shadow

NGC 2023 in the Horsehead's Shadow 
Image Credit & Copyright: Steve Mazlin, Mark Hanson, Warren Keller, Rex Parker, Tommy Tse,
and Peter Proulx (SSRO / PROMPT / CTIO)

Explanation: Carved by a bright young star in Orion's dusty molecular clouds, NGC 2023 is often overlooked in favor of the nearby dramatic silhouette of the Horsehead Nebula. In its own right it is seen as a beautiful star forming emission and reflection nebula though, a mere 1500 light-years distant. Surprisingly colorful and complex filaments are detailed in this rare NGC 2023 portrait. Scattered points of emission are also from the region's Herbig-Haro objects, associated with the energetic jets from newborn stars. The sharp telescopic view spans about 10 light-years at the estimated distance of NGC 2023. Off the right edge of the frame lies the more familiar cosmic Horsehead.

JoanMira - "Era uma vez...as flores" - Fotos

"Era uma vez...as flores"

29-03-2018

JoanMira

JoanMira - "Cor que até parece" - Fotos

"Cor que até parece" 

JoanMira -"Me and you" - Fotos

"Me and you"

JoanMira - "Sonho no Infinito" - Fotos

"Sonho no Infinito"

29-03-2018

JoanMira

JoanMira - "Primavera privada" - Fotos

"Primavera privada"

JoanMira - "Everytodas, uma cesta e um nabo" - Fotos

"Everytodas, uma cesta e um nabo"

29-03-2018

JoanMira

JoanMira - "Eram três amigas" - Fotos

"Eram três amigas"

28-03-2018

JoanMira

JonMira - "Smelling" - Fotos

"Smelling"

28-03-2018

JoanMira

Astronomy picture of the day - 2018 March 28 - Blue Moon Tree

Blue Moon Tree 
Image Credit & Copyright: Eric Houck Explanation: Does an alignment like this occur only once in a blue moon? No, although it was during a blue moon that this single-shot image was taken. During a full moon that happened to be the second of the month -- the situation that defines a blue moon -- the photographer created the juxtaposition in late January by quickly moving around to find just the right spot to get the background Moon superposed behind the arc of a foreground tree. Unfortunately, in this case, there seemed no other way than getting bogged down in mud and resting the camera on a barbed-wire fence. The arc in the oak tree was previously created by hungry cows in Knight's Ferry, California, USA. Quirky Moon-tree juxtapositions like this can be created during any full moon though, given enough planning and time. Another opportunity will arise this weekend, coincidently during another blue moon. Then, the second blue moon in 2018 will occur, meaning that for the second month this year, two full moons will appear during a single month (moon-th). Double blue-moon years are relatively rare, with the last occurring in 1999, and the next in 2037.

JoanMira - "Através da vidraça" - Fotos

"Através da vidraça"

28-03-2018

JoanMira

JoanMira - "A Primavera a crescer" - Fotos

"A Primavera a crescer"

28-03-2018

JoanMira

JoanMira - "what an angel : Haïzé" - Fotos

"what an angel : Haïzé"

28-03-2018

JoanMira

Astronomy picture of the day - 2018 March 27 - Mars Between Nebulas

Mars Between Nebulas 
Image Credit & Copyright: Sebastian Voltmer

Explanation: What that bright red spot between the Lagoon and Trifid Nebulas? Mars. This gorgeous color deep-sky photograph captured the red planet passing between the two notable nebulas -- cataloged by the 18th century cosmic registrar Charles Messier as M8 and M20. M20 (upper right of center), the Trifid Nebula, presents a striking contrast in red/blue colors and dark dust lanes. Across the bottom right is the expansive, alluring red glow of M8, the Lagoon Nebula. Both nebulae are a few thousand light-years distant. By comparison, temporarily situated between them both, is the dominant "local" celestial beacon Mars. Taken last week, the red planet was only about 10 light-minutes away.

JoanMira - "Dia... interrompido..." - Fotos

"Dia... interrompido..."

26-03-2018

JoanMira

No mundo dos leões - Imagens do Mundo, Africa do Sul - Animais

"No mundo dos leões"

- Don't talk me about Sporting...
- Sporting Clube de Braga ?
- No,  Lisbon !

Flores de Belgrado - Imagens do Mundo - Vegetais

Flores cobertas de neve em Belgrado (Servia).

Macacos de Jerusalem - Imagens do Mundo - Animais

"Macacos me mordam ; quem estaa espiando ?!"

Astronomy picture of the day - 2018 March 26 - The Coma Cluster of Galaxies

The Coma Cluster of Galaxies 
Image Credit: Russ Carroll, Robert Gendler, & Bob Frank; Dan Zowada Memorial Observatory

Explanation: Almost every object in the above photograph is a galaxy. The Coma Cluster of Galaxies pictured here is one of the densest clusters known - it contains thousands of galaxies. Each of these galaxies houses billions of stars - just as our own Milky Way Galaxy does. Although nearby when compared to most other clusters, light from the Coma Cluster still takes hundreds of millions of years to reach us. In fact, the Coma Cluster is so big it takes light millions of years just to go from one side to the other. Most galaxies in Coma and other clusters are ellipticals, while most galaxies outside of clusters are spirals. The nature of Coma's X-ray emission is still being investigated.

Brassaï - A noite parisiense - Fotografia

Um dos fotógrafos mais célebres de seu tempo, Brassaï registrou Paris de forma irreverente. A noite parisiense exerceu um enorme fascínio sobre ele, que não cansou de fotografá-la.

Pink Floyd - "Coming back to life" - Video - Music

"Coming back to life"

Astronomy picture of the day - 2018 March 25 - Announcing Nova Carinae 2018

Announcing Nova Carinae 2018 
Image Credit & Copyright: A. Maury & J. Fabrega

Explanation: How bright will Nova Carinae 2018 become? The new nova was discovered only last week. Although novas occur frequently throughout the universe, this nova, cataloged as ASASSN-18fv, is so unusually bright in theskies of Earth that it is now easily visible through binoculars in the southern hemisphere. Identified by the arrow, the nova occurs near the direction of the picturesque Carina Nebula. A nova is typically caused by a thermonuclear explosion on the surface of a white dwarf star that is accreting matter from a binary companion, although details of this outburst are currently unknown. Both professional and amateur astronomers will be monitoring this unusual stellar outburst in the coming weeks, looking to see how Nova Carinae 2018 evolves, including whether it becomes bright enough to be visible to the unaided eye.

Raquel Taraborelli - "Caminho de azaléias" - Pintura impressionista contemporânea

"Caminho de azaléias"

JoanMira - "Recordando amigos do Rio de Janeiro" - Fotos

"Recordando amigos do Rio de Janeiro"

24-03-2018

JoanMira

JoanMira - "REVOLUCION YA !" - Fotos

"REVOLUCION YA !"

24-03-2018

JoanMira

Leonard Cohen - "Halleluija" - Video - Music - Live

"Halleluija"

Astronomy picture of the day - 2018 March 24 - NGC 602 and Beyond

NGC 602 and Beyond 

Image Credit: X-ray: Chandra: NASA/CXC/Univ.Potsdam/L.Oskinova et al; 

Optical: Hubble: NASA/STScI; Infrared: Spitzer: NASA/JPL-Caltech

Explanation: Near the outskirts of the Small Magellanic Cloud, a satellite galaxy some 200 thousand light-years distant, lies 5 million year young star cluster NGC 602. Surrounded by natal gas and dust, NGC 602 is featured in thisstunning Hubble image of the region, augmented by images in the X-ray by Chandra, and in the infrared by Spitzer. Fantastic ridges and swept back shapes strongly suggest that energetic radiation and shock waves from NGC 602's massive young stars have eroded the dusty material and triggered a progression of star formation moving away from the cluster's center. At the estimated distance of the Small Magellanic Cloud, the Picture spans about 200 light-years, but a tantalizing assortment of background galaxies are also visible in this sharp multi-colored view. The background galaxies are hundreds of millions of light-years or more beyond NGC 602.

Robert Doisneau - Crianças de Paris - Fotografia

Robert Doisneau (14 de abril de 1912 – 1 de abril de 1994) foi um famoso fotógrafo nascido na cidade de Gentilly, Val-de-Marne, na França. Era um apaixonado por fotografia de rua e registrou a vida social das pessoas que viviam em Paris e seus arredores.

Astronomy picture of the day - 2018 March 23 - Rotating Moon from LRO

Rotating Moon from LRO 

Video Credit: LRO, Arizona State U., NASA

Explanation: No one, presently, sees the Moon rotate like this. That's because the Earth's moon is tidally locked to the Earth, showing us only one side. Given modern digital technology, however, combined with many detailed images returned by the Lunar Reconnaissance Orbiter (LRO), a high resolution virtual Moon rotation movie has been composed. The above time-lapse video starts with the standard Earth view of the Moon. Quickly, though, Mare Orientale, a large crater with a dark center that is difficult to see from the Earth, rotates into view just below the equator. From an entire lunar month condensed into 24 seconds, the video clearly shows that the Earth side of the Moon contains an abundance of dark lunar maria, while the lunar far side is dominated by bright lunar highlands. Currently, over 20 new missions to the Moon are under active development from four different countries, most of which have expected launch dates either this year or next.

Queen - "Who wants to live forever" - Video - Music

"Who wants to live forever"

Astronomy picture of the day - 2018 March 22 - NGC 253: Dusty Island Universe

NGC 253: Dusty Island Universe 
Image Credit & Copyright: Stefano Cancelli, Paul Mortfield

Explanation: Shiny NGC 253 is one of the brightest spiral galaxies visible, and also one of the dustiest. Some call it the Silver Dollar Galaxy for its appearance in small telescopes, or just the Sculptor Galaxy for its location within the boundaries of the southern constellation Sculptor. Discovered in 1783 by mathematician and astronomer Caroline Herschel, the dusty island universe lies a mere 10 million light-years away. About 70 thousand light-years across, NGC 253 is the largest member of the Sculptor Group of Galaxies, the nearest to our own Local Group of Galaxies. In addition to its spiral dust lanes, tendrils of dust seem to be rising from a galactic disk laced with young star clusters and star forming regions in this sharp color image. The high dust content accompanies frantic star formation, earning NGC 253 the designation of a starburst galaxy. NGC 253 is also known to be a strong source of high-energy x-rays and gamma rays, likely due to massive black holes near the galaxy's center. Take a trip through extragalactic space in this short video flyby of NGC 253.

Teresa Salgueiro - "O vento" - Video - Musica

"O vento"

Henri Cartier-Bresson - O pai do fotojornalismo - Fotografia

Henri Cartier-Bresson (Chanteloup-en-Brie, 22 de agosto de 1908 — Montjustin, 2 de agosto de 2004) foi umfotógrafo do século XX, considerado por muitos o pai do fotojornalismo.

Vanessa d'Azevedo - "Reguengos de Monsaraz" - Aguarelas

"Reguengos de Monsaraz"

Astronomy picture of the day - 2018 March 20 - Chicagohenge: Equinox in an Aligned City

Chicagohenge: Equinox in an Aligned City 
Image Credit & Copyright: Anthony Artese

Explanation: Sometimes, in a way, Chicago is like a modern Stonehenge. The way is east to west, and the time is today. Today, and every equinox, the Sun will set exactly to the west, everywhere on Earth. Therefore, today inChicago, the Sun will set directly down the long equatorially-aligned grid of streets and buildings, an event dubbed #chicagohenge. Featured here is a Chicago Henge picture taken during the last equinox in mid-September of 2017 looking along part of Upper Wacker Drive. Many cities, though, have streets or other features that are well-aligned to Earth's spin axis. Therefore, quite possibly, your favorite street may also run east - west. Tonight at sunset, with a quick glance, you can actually find out.

Astronomy picture of the day - 2018 March 17 - The Crab from Space

The Crab from Space 
Image Credit: NASA - X-ray: CXC, Optical: STSCI, Infrared: JPL-Caltech,

Explanation: The Crab Nebula is cataloged as M1, the first object on Charles Messier's famous list of things which are not comets. In fact, the Crab is now known to be a supernova remnant, expanding debris from the death explosion of a massive star. This intriguing false-color image combines data from space-based observatories, Chandra, Hubble, and Spitzer, to explore the debris cloud in X-rays (blue-white), optical (purple), and infrared (pink) light. One of the most exotic objects known to modern astronomers, the Crab Pulsar, a neutron star spinning 30 times a second, is the bright spot near picture center. Like a cosmic dynamo, this collapsed remnant of the stellar core powers the Crab's emission across the electromagnetic spectrum. Spanning about 12 light-years, the Crab Nebula is 6,500 light-years away in the constellation Taurus.

JoanMira - "Primavera à porta" - Fotos

- Quem bateu?

- é a Primavera à porta.

Astronomy picture of the day - 2018 March 16 - The Seagull and the Duck

The Seagull and the Duck 
Image Credit & Copyright: Raul Villaverde Fraile

Explanation: Seen as a seagull and a duck, these nebulae are not the only cosmic clouds to evoke images of flight. But both are winging their way across this broad celestial landscape, spanning almost 7 degrees across planet Earth's night sky toward the constellation Canis Major. The expansive Seagull (top center) is itself composed of two major cataloged emission nebulae. Brighter NGC 2327 forms the head with the more diffuse IC 2177 as the wings and body. Impressively, the Seagull's wingspan would correspond to about 250 light-years at the nebula's estimated distance of 3,800 light-years. At the lower right, the Duck appears much more compact and would span only about 50 light-years given its 15,000 light-year distance estimate. Blown by energetic winds from an extremely massive, hot star near its center, the Duck nebula is cataloged as NGC 2359. Of course, the Duck's thick body and winged appendages also lend it the slightly more dramatic popular moniker, Thor's Helmet.

Inês Dourado - "Pôr-do-sol na Caldeira da Moita" - Aguarela

"Pôr-do-sol na Caldeira da Moita"

JoanMira - "Alone again..." - Fotos

"Alone again..."

15-03-2018

JoanMira

Astronomy picture of the day - 2018 March 15 - Catalog Entry Number 1

Catalog Entry Number 1 
Image Credit & Copyright: Bernhard Hubl (CEDIC)

Explanation: Every journey has first step and every catalog a first entry. First entries in six well-known deep sky catalogs appear in these panels, from upper left to lower right in chronological order of original catalog publication. From 1774, Charles Messier's catalog entry number 1 is M1, famous cosmic crustacean and supernova remnant the Crab Nebula. J.L.E. Dreyer's (not so new) New General Catalog was published in 1888. A spiral galaxy in Pegasus, his NGC 1 is centered in the next panel. Just below it in the frame is another spiral galaxy cataloged as NGC 2. In Dreyer's follow-on Index Catalog (next panel), IC 1 is actually a faint double star, though. Now recognized as part of the Perseus molecular cloud complex, dark nebula Barnard 1 begins the bottom row from Dark Markings of the Sky, a 1919 catalog by E.E. Barnard. Abell 1 is a distant galaxy cluster in Pegasus, from George Abell's 1958 catalog of Rich Clusters of Galaxies. The final panel is centered on vdB 1, from Sidney van den Bergh's 1966 study. The pretty, blue galactic reflection nebula is found in the constellation Cassiopeia.

JoanMira - "Ao cair do dia" - Fotos

"Ao cair do dia"

14-03-2018

JoanMira

Raquel Taraborelli - "Vasos de gerânios ensolarados" - Pintura impressionista contemporânea

"Vasos de gerânios ensolarados"

Mort de Stephen Hawking : la communauté scientifique salue "un ambassadeur de la science" - Science et technologie

L’astrophysicien britannique, spécialiste des trous noirs, est mort aujourd'hui à 76 ans. Scientifiques mais aussi responsables scientifiques lui rendent hommage.

« Un être unique, dont on se souviendra avec affection non seulement à Cambridge, mais dans le monde entier », a écrit Stephen Toope, le vice-président de l’université de Cambridge, où Stephen Hawking avait étudié et travaillait, quelques minutes après l’annonce de la mort du physicien, mercredi 14 mars. "Son exceptionnelle contribution au savoir scientifique, aux mathématiques et à la vulgarisation laisse une contribution indélébile", a-t-il ajouté.

Sur Twitter, la NASA a salué "un physicien de renom et un ambassadeur de la science". "Ses découvertes ont ouvert un univers de possibilités que nous et le monde continuons à explorer", a déclaré l’agence spatiale américaine.

"D'où vient l'Univers? Comment et pourquoi a-t-il commencé? Connaîtra-t-il une fin, et si oui, comment?"

Voici ce qu'écrivait Stephen Hawking dans la préface de son livre "Une brève histoire du temps" paru en 1988.

Astronomy picture of the day - 2018 March 14 - Night Sky Highlights: March to May

Night Sky Highlights: March to May 
Illustration Credit & Copyright: Universe2go.com

Explanation: What might you see in the night sky over the next few months? The featured graphic gives a few highlights. Viewed as a clock face centered at the bottom, sky events in March fan out toward the left, April toward the top, and May 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.Sky highlights this season include a bright Venus in the evening sky during March, the Lyrids meteor shower during April, and Jupiter entering the evening sky during May. As true in every season, the International Space Station (ISS) can be sometimes be found drifting across your sky if you know just when and where to look.

Astronomy picture of the day - 2018 March 13 - The Complete Galactic Plane: Up and Down

The Complete Galactic Plane: Up and Down 
Image Credit & Copyright: Moophz Himself (Maroun Habib)

Explanation: Is it possible to capture the entire plane of our galaxy in a single image? Yes, but not in one exposure -- and it took some planning to do it in two. The top part of the featured image is the night sky above Lebanon, north of the equator, taken in 2017 June. The image was taken at a time when the central band of the Milky Way Galaxy passed directly overhead. The bottom half was similarly captured six months later in latitude-opposite Chile, south ofEarth's equator. Each image therefore captured the night sky in exactly the opposite direction of the other, when fully half the Galactic plane was visible. The southern half was then inverted -- car and all -- and digitally appended to the top half to show the entire central band of our Galaxy, as a circle, in a single image. Many stars and nebulas are visible, with the Large Magellanic Cloud being particularly notable inside the lower half of the complete galactic circle.

Bob Dylan - "Cross the green mountain" - Video - Music

"Cross the green mountain"

Inês Dourado - "Beco das Cruzes" - Aguarela

"Beco das Cruzes"

Astronomy picture of the day - 2018 March 12 - Flying over the Earth at Night II

Flying over the Earth at Night II 
Video Credit: NASA, Gateway to Astronaut Photography; Music: The Low Seas (The 126ers)

Explanation: What would it be like to orbit the Earth? The International Space Station (ISS) does this every 90 minutes, and sometimes the astronauts on board take image sequences that are made into videos. The featured time-lapse video shows many visual spectacles of the dark Earth below. First, as the video begins, green and red auroras are visible on the upper left above white clouds. Soon city lights come into view, and it becomes clear you are flying overNorth America, eventually passing over Florida. In the second sequence you fly over Europe and Africa, eventually passing over the Nile River. Brief flashes of light are lightning in storms. Stars far in the distance can be seen rising through the greenish-gold glow of the Earth's atmosphere.

Astronomy picture of the day - 2018 March 11 - Dual Particle Beams in Herbig-Haro 24

Dual Particle Beams in Herbig-Haro 24 
Image Credit: NASA, ESA, Hubble Heritage (STScI/AURA)/Hubble-Europe Collaboration;
Acknowledgment: D. Padgett (NASA's GSFC), T. Megeath (U. Toledo), B. Reipurth (U. Hawaii)

Explanation: This might look like a double-bladed lightsaber, but these two cosmic jets actually beam outward from a newborn star in a galaxy near you. Constructed from Hubble Space Telescope image data, the stunning scene spans about half a light-year across Herbig-Haro 24 (HH 24), some 1,300 light-years away in the stellar nurseries of the Orion B molecular cloud complex. Hidden from direct view, HH 24's central protostar is surrounded by cold dust and gas flattened into a rotating accretion disk. As material from the disk falls toward the young stellar object it heats up. Opposing jets are blasted out along the system's rotation axis. Cutting through the region's interstellar matter, the narrow, energetic jets produce a series of glowing shock fronts along their path.

Astronomy picture of the day - 2018 March 10 - Phases of the Moon

Phases of the Moon 
Image Credit & Copyright: Jean-Francois Gout, Tom Polakis

Explanation: Look at the Moon every night and its visible sunlit portion gradually changes. In phases progressing from New Moon to Full Moon to New Moon again, a lunar cycle or lunation is completed in about 29.5 days. Top left to bottom right, these frames show the range of lunar phases for 25 consecutive nights beginning on January 18, following an almost complete lunation. They skip the 2 days just after and 2 days before New Moon, when the lunar phase is at best a narrow crescent, close to the Sun and really hard to see. Of course, mostly clear Arizona night skies and a little help from a friend were required to complete this lunar cycle project, imaging in early evening for the first half and late evening and early morning for the second half of the lunation. For extra credit, the cycle was centered on the Full Moon of January 31. That was the second Full Moon in January, when the Moon was near lunar orbit perigee and took on reddish hues during a total lunar eclipse.

Monet with Beethovens Symphony Nr. 7 - Slides - Pintura

"Monet with Beethovens Symphony Nr. 7" 

Status Quo - "In the Army now" - Video - Music

"In the Army now"

Astronomy picture of the day - 2018 March 9 - Horsehead: A Wider View

Horsehead: A Wider View 
Composition and Processing: Robert Gendler
Image Data: ESO, VISTA, HLA, Hubble Heritage Team (STScI/AURA)

Explanation: Combined image data from the massive, ground-based VISTA telescope and the Hubble Space Telescope was used to create this wide perspective of the interstellar landscape surrounding the famous Horsehead Nebula. Captured at near-infrared wavelengths, the region's dusty molecular cloud sprawls across the scene that covers an angle about two-thirds the size of the Full Moon on the sky. Left to right the frame spans just over 10 light-years at the Horsehead's estimated distance of 1,600 light-years. Also known as Barnard 33, the still recognizable Horsehead Nebula stands at the upper right, the near-infrared glow of a dusty pillar topped with newborn stars. Below and left, the bright reflection nebula NGC 2023 is itself the illuminated environs of a hot young star. Obscuring clouds below the base of the Horsehead and on the outskirts of NGC 2023 show the tell-tale far red emission of energetic jets, known as Herbig-Haro objects, also associated with newborn stars.

Astronomy pictures of the day - 2018 March 8 - Cyclones at Jupiter's North Pole

Cyclones at Jupiter's North Pole 
Image Credit: NASA, JPL-Caltech, SwRI, ASI, INAF, JIRAM

Explanation: Juno's Jovian Infrared Auroral Mapper data was used to construct this stunning view of cyclones at Jupiter's North Pole. Measuring the thermal emission from Jovian cloud tops, the infrared the observations are not restricted to the hemisphere illuminated by sunlight. They reveal eight cyclonic features that surround a cyclone about 4,000 kilometers in diameter, just offset from the giant planet's geographic North Pole. Similar data show a cyclone at the Jovian South Pole with five circumpolar cyclones. The South Pole cyclones are slightly larger than their northern cousins. Cassini data has shown that gas giant Saturn's north and south poles each have a single cyclonic storm system.

Astronomy picture of the day - 2018 March 7 - Arcs, Jets, and Shocks near NGC 1999

Arcs, Jets, and Shocks near NGC 1999 
Image Credit & Copyright: Mark Hanson

Explanation: This tantalizing array of nebulas and stars can be found about two degrees south of the famous star-forming Orion Nebula. The region abounds with energetic young stars producing jets and outflows that push through the surrounding material at speeds of hundreds of kilometers per second. The interaction creates luminous shock waves known as Herbig-Haro (HH) objects. For example, the graceful, flowing arc just right of center is cataloged as HH 222, also called the Waterfall Nebula. Seen below the Waterfall, HH 401 has a distinctive cone shape. The bright bluish nebula below and left of center is NGC 1999, a dusty cloud reflecting light from an embedded variable star. The entire cosmic vista spans over 30 light-years, near the edge of the Orion Molecular Cloud Complex some 1,500 light-years distant.

Van Gogh - Pintura animada

"Van Gogh"

Taberna em Cuba - Baixo Alentejo - Portugal - Video - Musica

"Taberna em Cuba"

Teresa Salgueiro - "A estrada" - Video - Musica

"A estrada"

Astronomy picture of the day - 2018 March 6 - Colorful Airglow Bands Surround Milky Way

Colorful Airglow Bands Surround Milky Way 
Image Credit & Copyright: Xiaohan Wang

Explanation: Why would the sky glow like a giant repeating rainbow? Airglow. Now air glows all of the time, but it is usually hard to see. A disturbance however -- like an approaching storm -- may cause noticeable rippling in theEarth's atmosphere. These gravity waves are oscillations in air analogous to those created when a rock is thrown in calm water. Red airglow likely originates from OH molecules about 87-kilometers high, excited by ultraviolet light from the Sun, while orange and green airglow is likely caused by sodium and oxygen atoms slightly higher up. While driving near Keluke Lake in Qinghai Provence in China, the photographer originally noticed mainly the impressive central band of the Milky Way Galaxy. Stopping to photograph it, surprisingly, the resulting sensitive camera image showed airglow bands to be quite prominent and span the entire sky. The featured image has been digitally enhanced to make the colors more vibrant.