Immagine della settimana

15 Novembre 2010: Among the myriad of stars in this image shines NGC 2257, a collection of cosmic gems bound tightly by gravity. Many billions of years old, but still sparkling brightly, it is an eye-catching astronomical object. NGC 2257 is a globular cluster, the name given to the roughly spherical concentrations of stars that orbit galactic cores, but are often found far out from the centres in the halo areas of galaxies. Globular clusters contain very old stars, being typically over 10 billion years old, and can therefore be used like a "fossil record" to learn more about the Universe’s past. They are densely packed, with tens to hundreds of thousands of stars gathered within a diameter of just a few tens of light-years. NGC 2257 lies on the outskirts of the Large Magellanic Cloud (LMC), a satellite galaxy of our own Milky Way. It is one of 15 very old globular ...

08 Novembre 2010: This impressive image, taken on 10 May 2010 by ESO astronomer Yuri Beletsky, beautifully depicts the sky above Paranal. One of the 8.2-metre telescopes of ESO's Very Large Telescope, Yepun, Unit Telescope 4, is seen against the wonderful backdrop of the myriad of stars and dust that makes up the Milky Way. A laser beam is coming out of Yepun, aiming perfectly at the Galactic Centre. When used with the adaptive optics system the artificial star created by the beam allows the telescope to obtain images and spectra that are free from the blurring effect of the atmosphere. When this image was taken, astronomers Stefan Gillessen and Hauke Enkel were using the SINFONI instrument, together with the laser guide star facility, to study the centre of our Milky Way, where a supermassive black hole is lurking. The field of view of the image is very wide, about 180 degrees. One ...

01 Novembre 2010: Gli astronomi, usando i dati ottenuti con il Very Large Telescope (VLT) dell'ESO, presso l'osservatorio Paranal in Cile, hanno creato un impressionante composito della nebula Messier 17, anche conosciuta come Omega Nebula o Nebula del Cigno. L'immagine, simile ad un dipinto, mostra vaste nuvole di gas e polvere illuminate dall'intensa radiazione proveniente da stelle giovani. L'immagine mostra una regione centrale attraverso circa 15 anni luce, anche se l'intera nebula e' anche piu' larga, circa 40 anni luce in totale. Messier 17 e' nella costellazione del Sagittario, circa 6000 anni luce dalla terra. E' un bersaglio diffuso tra astronomi amatoriali, che possono ottenere immagini di buona qualita' con piccoli telescopi. Queste profonde VLT osservazioni sono state fatte con vicine onde infrarosse con lo strumento ISAAC. I filtri usati erano J (1.23 µm, mostrato in blu), H (1.6 µm, mostrato in verde) e K (2.2. µm, mostrato in rosso). Nel centro dell'immagine ...

25 Ottobre 2010: Le stelle ruotano intorno al polo celeste del nord durante una notte all'osservatorio ESO a La Silla, nel nord del Cile. Le parti sfocate nelle scie sulla destra sono dovute dalle Nuvole di Magellano, due galassie molto piccole vicino alla VIa Lattea. La cupola vista nell'immagine ospita il telescopio ESO di 3.6 metri e HARPS (High Accuracy Radial velocity Planet Searcher), il piu' famoso cacciatore di pianeti extraterrestri al mondo. L'edificio rettangolare visto nella parte in basso a destra dell'immagine contiene il telescopio TAROT di 0.25 metri, progettato per reagire molto velocemente quando si localizza un'esplosione gamma-ray. Tra gli altri telescopi a La Silla e' compreso anche il telescopio di 2.2 metri, MGP/ESO, e il New Technology Telescope di 3.58 metri, il primo telescopio ad usare active optics e, percio', il precursore di tutti i moderni grandi telescopi. La Silla e' stato il primo luogo di osservazione dell'ESO ed e' ...

18 Ottobre 2010: The Sun sets at ESO’s Very Large Telescope (VLT) in this image. Taken at the observatory on Cerro Paranal in the dry Atacama Desert of Chile, the observatory’s four 8.2-metre telescopes can be seen preparing for the night ahead. Three of the VLT’s four Auxiliary 1.8-metre Telescopes (AT), used for interferometry, are also visible. The telescopes are seen reflected in the protection cover of one of the AT stations. The ATs are mounted on tracks and can be moved between precisely defined observing positions from where the beams of collected light are combined in the interferometric laboratory. The ATs are very unusual telescopes, as they are self-contained in their own ultra-compact protective domes, and travel with their own electronics, ventilation, hydraulics and cooling systems. Each AT has a transporter that lifts the telescope and moves it from one position to the other. At 2600 metres above sea level, the observing ...

11 Ottobre 2010: ESO has grown significantly since 1980, when its European staff originally moved from offices at CERN to a dedicated headquarters building in Garching, near Munich, Germany. In the intervening three decades the number of ESO’s member states has increased from six to fourteen, and the organisation has achieved milestones such as the First Light of the New Technology Telescope at La Silla and of the Very Large Telescope at Paranal, becoming in the process the most productive observatory in the world. Today, ESO is constructing the Atacama Large Millimeter/submillimeter Array at Chajnantor in collaboration with international partners, and is in the detailed design phase of a 40-metre-class European Extremely Large Telescope, which will be “the world’s biggest eye on the sky”. Over the years, the number of ESO staff working in Garching has increased from about 100 to about 450, as the organisation has grown and tackled these exciting new ...

04 Ottobre 2010: Two of the Atacama Large Millimeter/submillimeter Array (ALMA) 12-metre antennas gaze at the sky at the observatory’s Array Operations Site (AOS), high on the Chajnantor plateau at an altitude of 5000 metres in the Chilean Andes. Eight antennas have been installed at the AOS since November 2009. More antennas will be installed on the Chajnantor plateau during the next months and beyond, allowing astronomers to start producing early scientific results with the ALMA system around late 2011. After this, the interferometer will steadily grow to reach its full scientific potential, with at least 66 antennas. ALMA is the largest ground-based astronomy project in existence, and will comprise a giant array of 12-metre submillimetre quality antennas, with baselines of up to about 16 kilometres. An additional, compact array of 7-metre and 12-metre antennas will complement the main array. The ALMA project is an international collaboration between Europe, East Asia and North ...

27 Settembre 2010: This unusual and artistic image, made using a technique known as "solargraphy" in which a pinhole camera captures the movement of the Sun in the sky over many months, was taken from the Atacama Pathfinder Experiment (APEX) telescope on the plateau of Chajnantor. The plateau is also where ESO, together with international partners, is building the Atacama Large Millimeter/submillimeter Array (ALMA). The solar trails in the image were recorded over half a year and clearly show the quality of the 5000-metre altitude site, high in the Chilean Andes, for astronomical observations. The idea for creating the solargraphs at ESO's telescopes came from Bob Fosbury, an astronomer based at ESO Headquarters in Germany, after learning about the technique from Finnish artist Tarja Trygg. Trygg provided the cameras, known as "cans". The cans are constructed from small black plastic canisters used for storing 35 mm film cassettes. A pinhole in a sheet ...

20 Settembre 2010: After the Sun sets at ESO’s Paranal Observatory darkness descends, but the black sky is speckled with a glorious myriad of sparkling stars. This 15-second exposure demonstrates just how dazzling the skies above Paranal are. Located high in the Atacama Desert in Chile far from any sources of light pollution, on a clear moonless night it is possible to see your shadow cast by the light of the Milky Way alone. Says visual artist and ESO Photo Ambassador José Francisco Salgado, “The skies at Paranal are among the darkest and steadiest I have photographed. I love photographing observatories and at Paranal it's incredible how you can still see just with starlight and zodiacal light!” In the image the stars of the Milky Way seem to be pouring forth from the open dome of the telescope. The brightest patch close to the telescope is the Carina Nebula (NGC 3372), which contains ...

13 Settembre 2010: Spiralling around, 61 million light-years away in the constellation Fornax (the Furnace), NGC 1365 is enormous. At 200000 light-years across, it is one of the largest galaxies known to astronomers. This, plus the sharply defined bar of old stars across its structure is why it is also known as the Great Barred Spiral Galaxy. Astronomers think that the Milky Way may look very similar to this galaxy, but at half the size. The bright centre of the galaxy is thought to be due to huge amounts of superhot gas ejected from the ring of material circling a central black hole. Young luminous hot stars, born out of the interstellar clouds, give the arms a prominent appearance and a blue colour. The bar and spiral pattern rotates, with one full turn taking about 350 million years. This image combines observations performed through three different filters (B, V, R) with the 1.5-metre ...

06 Settembre 2010: A meta' Agosto del 2010 ESO Photo Ambassador Yuri Beletsky ha scattato questa fantastica foto delloOsservatorio ESO a Paranal. Un gruppo di astronomi stavano osservando il centro della Via Lattea usando la struttura stella laser guida in Yepun, uno dei quattro Unit Telescopes del Very Large Telescope (VLT). Il raggio di Yepun attraversa l'atmosfera del maestoso cielo del sud e crea una stella artificiale ad un'altitudine di 90 km nella mesosfera della terra. La Stella Laser Guida (LGS) fa parte del VLTadaptive optics system ed e' usato come referenza per corregere l'effetto sfuocato dell'atmosfera sulle immagini. Il colore del laser e' esattamente calibrato per energizzare uno strato di atomi di sodio ce si trovano in uno dei piu' superficiali strati dell'atmosfera - si puo' riconoscere il colore familiare delle lampade stradali al sodio nel colore del laser. Si pensa che questo strato di atomi di sodio sia un resto lasciato ...

30 Agosto 2010: NGC 5426 and NGC 5427 are two spiral galaxies of similar sizes engaged in a dramatic dance. It is not certain that this interaction will end in a collision and ultimately a merging of the two galaxies, although the galaxies have already been affected. Together known as Arp 271, this dance will last for tens of millions of years, creating new stars as a result of the mutual gravitational attraction between the galaxies, a pull seen in the bridge of stars already connecting the two. Located 90 million light-years away towards the constellation of Virgo (the Virgin), the Arp 271 pair is about 130 000 light-years across. It was originally discovered in 1785 by William Herschel. Quite possibly, our own Milky Way will undergo a similar collision in about five billion years with the neighbouring Andromeda galaxy, which is now located about 2.6 million light-years away from the Milky Way. ...

23 Agosto 2010: During a night at ESO’s Very Large Telescope (VLT), the stars seem to rotate around the southern celestial pole. The skies over Paranal provide splendid observing opportunities for the astronomers below. At the observatory on Cerro Paranal in the dry Atacama Desert of Chile, one of the observatory’s four 8.2-metre telescopes can be seen on the right performing its nightly task of looking at the heavens. Two of the four 1.8-metre Auxiliary Telescopes are also seen in the picture. The dry, high environment at 2600 metres above sea level, and the extraordinarily advanced equipment makes observing time at the VLT highly sought after by astronomers around the world.

16 Agosto 2010: Every year in mid-August the Perseid meteor shower has its peak. Meteors, colloquially known as “shooting stars”, are caused by pieces of cosmic debris entering Earth’s atmosphere at high velocity, leaving a trail of glowing gases. Most of the particles that cause meteors are smaller than a grain of sand and usually disintegrate in the atmosphere, only rarely reaching the Earth’s surface as a meteorite. The Perseid shower takes place as the Earth moves through the stream of debris left behind by Comet Swift-Tuttle. In 2010 the peak was predicted to take place between 12–13 August 2010. Despite the Perseids being best visible in the northern hemisphere, due to the path of Comet Swift-Tuttle's orbit, the shower was also spotted from the exceptionally dark skies over ESO’s Paranal Observatory in Chile. In order not to miss any meteors in the display, ESO Photo Ambassador Stéphane Guisard set up 3 cameras ...

09 Agosto 2010: Haro 11 appears to shine gently amid clouds of gas and dust, but this placid facade belies the monumental rate of star formation occurring in this “starburst” galaxy. By combining data from ESO’s Very Large Telescope and the NASA/ESA Hubble Space Telescope, astronomers have created a new image of this incredibly bright and distant galaxy. The team of astronomers from Stockholm University, Sweden, and the Geneva Observatory, Switzerland, have identified 200 separate clusters of very young, massive stars. Most of these are less than 10 million years old. Many of the clusters are so bright in infrared light that astronomers suspect that the stars are still emerging from the cloudy cocoons where they were born. The observations have led the astronomers to conclude that Haro 11 is most likely the result of a merger between a galaxy rich in stars and a younger, gas-rich galaxy. Haro 11 is found to ...

02 Agosto 2010: Nella ricerca di mondi distanti, pochi telescopi hanno avuto cosi' tanto successo come il telescopio 3.6 metri (ESO's 3.6-metre telescope) e il Swiss 1.2-metre Leonhard Euler Telescope, che sono mostrati in questa immagine. Il telescopio di 3.6 metri fornisce dimora a HARPS (High Accuracy Radial velocity Planet Searcher), uno spettrografo di una precisione senza pari e possessore di diversi record nel campo della ricerca di pianeti extraterrestri, compresa la scoperta dell'ultimo enorme pianeta extraterrestre e di quello piu' piccolo mai misurato. Insieme a HARPS, il telescopio Leonhard Euler ha permesso agli astronomi di scoprire sei pianeti extraterrestri da un campione di 27 che orbitavano nella direzione opposta alla rotazione della loro stella ospitante - fornendo un'inaspettata e importante sfida alle recenti teorie sulla formazione di pianeti. All'altezza di 2400 metri sopra il livello del mare nella parte sud del deserto Atacama in Cile, La Silla e' stato il primo luogo ...

26 Luglio 2010: NGC 4027, also known as Arp 22, stretches its single extended spiral arm in this face-on image. Located about 75 million light-years away in the constellation of Corvus (the Crow), this barred spiral galaxy is identified as a peculiar galaxy by this extended arm, thought to be the result of a collision with another galaxy millions of years ago — most likely a small galaxy known as NGC 4027A. NGC 4027 is part of the NGC 4038 Group, a group of galaxies that also contains the famous distorted couple known as the Antennae Galaxies (see eso0209 and heic0615). This image is based on data collected with the ESO Faint Object Spectrograph and Camera (EFOSC) attached to the 3.58-metre New Technology Telescope (NTT) at the ESO La Silla Observatory in Chile. The data were collected through three broadband filters (B, V and R) and two narrowband filters (Hα and doubly ionised ...

19 Luglio 2010: A European Atacama Large Millimeter/submillimeter Array (ALMA) antenna takes a ride on Lore, one of the ALMA Transporters, at the 2900-metre altitude Operations Support Facility in the Chilean Andes. This took place on 23 June 2010, and was the first time that European antennas have been lifted with the transporters, a procedure that was fully successful, with both moves completed in a single day. The first two European antennas for ALMA have been moved to two new outdoor foundation pads in order to perform tests of their dish surface accuracy. In this process, known as holography, the antennas observe the signals from a special transmitter located on a nearby tower. In order to allow parallel assembly of several antennas, two new foundations have recently been built. As the newly built foundations lie between the original positions of the two antennas and the holography tower, the antennas were moved to the ...

12 Luglio 2010: Yesterday 11 July 2010, between 20:15 and 22:51 CEST, the path of a total solar eclipse streaked across the Pacific Ocean touching several small islands including Tuamotu in French Polynesia, Mangaia in the Cook Islands and Chile's Easter Island. The total eclipse brushed the southern mainland of Chile, and was seen as a partial eclipse in the rest of the country. At ESO's Paranal Observatory ESO Photo Ambassador Yuri Beletsky snapped this photo near the mid-point of the eclipse. On the mainland of Chile, outside the zone of complete darkness, the partial eclipse was visible from ESO's Paranal Observatory. With the naked eye, eclipses are difficult — and dangerous — to watch until they reach totality, as the Sun is so bright. But a filter reduces the glare and here reveals the advancing disk of the Moon as it moves across the face of the Sun. In this photograph, the ...

28 Giugno 2010: NGC 3628 is a spiral galaxy and a member of a small, but conspicuous group of galaxies located about 35 million light-years away, toward the constellation of Leo (the Lion). The other distinguished members of this family, known collectively as the Leo Triplet, are two well-known prominent spiral galaxies, Messier 65 and Messier 66 (not seen on the image), which were both discovered in 1780 by famous French comet hunter Charles Messier. NGC 3628 is the faintest of the trio and escaped Messier’s observations with his rather small telescope. It was discovered and catalogued by William Herschel only four years later. NGC 3628 hides its spiral structure because it is seen perfectly edge-on, exactly as we observe the Milky Way on a clear night. Its most distinctive feature is a dark band of dust that lies across the plane of the disc and which is visibly distorted outwards, as a ...