Photo de la semaine

6 juin 2011: This spectacular approximately 230-degree panoramic photograph of ESO’s Very Large Telescope (VLT), taken by ESO Photo Ambassador Gerhard Hüdepohl, gives us an inspiring view of a slice of the sky, encompassing both our nearest celestial neighbour and star clusters hundreds of light-years away. The VLT’s four large Unit Telescopes dominate the foreground. With gigantic mirrors 8.2 metres across, they allow us to peer into space and see things four billion times fainter than we can see with our eyes alone. Also visible are the round enclosures of the four 1.8-metre Auxiliary Telescopes, one to the left of the Unit Telescopes and three to the right. This observatory has an excellent location, on Cerro Paranal in the Chilean Atacama Desert. It is so high, at 2600 metres altitude, that what looks like the rippling ocean to the west, on the left of the image, is in fact the cloud layer below ...

30 mai 2011: This is a helicopter view of the Atacama Large Millimeter/submillimeter Array (ALMA) Operations Support Facility (OSF) site. In the foreground is the AEM Consortium’s [1] facility where the European antennas are assembled and tested. Seven of the 25 European antennas can be seen, pointing towards the sky. More parts, including a receiver cabin and antenna base, await the next assembly. Each antenna has a dish 12 metres in diameter, and weighs about 95 tonnes. Once an antenna is assembled and ready, it is handed over to the ALMA project and moved to the nearby OSF technical area, which is the area in the background, where more antennas can be seen. Here, it is integrated into the rest of the observatory’s systems. Finally, after further tests by the ALMA team, it is moved from the 2900 metres high OSF to its workplace, the Array Operation Site (AOS), located at an altitude ...

23 mai 2011: The first of twelve 7-metre antennas has been handed over to the Atacama Large Millimeter/submillimeter Array (ALMA) observatory in Chile. ALMA will have an array of fifty antennas with 12-metre diameter dishes, as well as a system known as the Atacama Compact Array (ACA), provided by Japan, of which this new 7-metre antenna is part. The ACA will have a total of twelve 7-metre dishes and four 12-metre dishes, and will be particularly important for ALMA’s observations of the broader structure in extended astronomical objects such as giant clouds of molecular gas. The 7-metre antenna is seen here at the ALMA Operations Support Facility (OSF), at an altitude of 2900 metres in the foothills of the Chilean Andes. These antennas are being provided by Japan through a contract with MELCO (Mitsubishi Electric Corporation). The antennas are manufactured in Japan, then disassembled and shipped to Chile. They are reassembled and tested ...

16 mai 2011: This new image of the spiral galaxy NGC 3244 was taken with the help of the President of Czechia, Václav Klaus, during his visit to ESO’s Paranal Observatory [1], on the night of 6 April 2011. Czechia joined ESO in 2007, and this was the first visit of the country’s President to an ESO site. This galaxy has attracted considerable interest from astronomers over the past nine months, thanks to the violent death of one of its stars, which was discovered on 27 June 2010. This supernova explosion, now known as Supernova 2010ev (SN 2010ev), is still visible as the — now faint — blue dot nestled within one of the thick spiral arms just to the left of the galaxy’s nucleus. To the right of the galaxy, an unremarkable foreground star in our own Milky Way, TYC 7713-527-1, shines brightly enough to catch our attention. Although the star seems ...

9 mai 2011: Une éclipse lunaire totale est un impressionant spectacle mais elle donne également une autre vue: un sombre ciel nocturne sans aucune lumière venant de la Lune. À Cerro Paranal dans le désert d'Atacama au Chili, un des endroits les plus reculés de la planète, l'éloignement de toute pollution lumineuse permet au ciel d'être tellement remarquable durant une éclipse lunaire totale. Ce panorama, pris par l'ambassadeur photo ESO Yuri Beletsky, montre la vue du ciel étoilé sur le site du Very Large Telescope (VLT) de l'ESO à Cerro Paranal durant une éclipse lunaire totale le 21 Décembre 2010. Le disque rougeâtre de la Lune est visible sur la droite de l'image, tandis que la Voie Lactée forme une arche à travers le paysage nocturne. Une autre lueur est visible autour de la brillante planète Vénus dans le coin en bas à gauche. Ce phénomène, connu sous le nom de lumière du ...

2 mai 2011: ESO Photo Ambassador Gerhard Hüdepohl has captured yet another rare sight. Yesterday, in the morning of 1 May 2011, about an hour before sunrise, five of our Solar System’s eight planets and the Moon could be seen from Paranal. The four planets in the sky were Mercury, Venus, Mars and Jupiter, and they were joined by the crescent Moon to create this wonderful photo opportunity of a planetary conjunction — two or more celestial bodies seen near each other in the sky, usually from the Earth. In this photo, the bright crescent of the Moon is illuminated by the Sun (which is just below the horizon), while the darker part receives only light reflected from the surface of the Earth. Venus is the highest and brightest planet, with Mercury below and to the right. Jupiter is directly below Venus, but much closer to the horizon. Mars can be seen just ...

25 avril 2011: On Cerro Paranal, the 2600-metre-high mountain in Chile’s Atacama Desert that is home to ESO’s Very Large Telescope, the atmospheric conditions are so exceptional that fleeting events such as the green flash of the setting Sun are seen relatively frequently. Now, however, ESO Photo Ambassador Gerhard Hüdepohl has captured an even rarer sight: a green flash from the Moon, instead of the Sun. The photographs are very probably the best ever taken of the Moon’s green flash. Gerhard was surprised and delighted to catch the stunning green flash in this series of photographs of the setting full Moon crossing the horizon, taken on a clear early morning from the Paranal Residencia. The Earth’s atmosphere bends, or refracts, light — rather like a giant prism. The effect is greater in the lower denser layers of the atmosphere, so rays of light from the Sun or Moon are curved slightly downwards. Shorter ...

18 avril 2011: Some places on Earth can seem like alien environments, as this stunning 360 degree panorama shows. It is not the strange surface of an exoplanet, but rather the Chajnantor Plateau in the Chilean Andes. This unearthly location is home to ALMA, the Atacama Large Millimeter/submillimeter Array. Chajnantor was chosen because the rarefied atmosphere above this very high site is so dry that, unlike at most other places on Earth, it is largely transparent to the wavelengths of light that ALMA is designed to detect. At the centre of the image, the darker, rounded shape of the peak of Cerro Chajnantor, 5600 metres high, can be spotted, followed slightly to the left in the far distance by the conical shape of the 5930-metre Licancabur volcano. The flat area in front, at an altitude of 5000 metres, is the Chajnantor Plateau, the ALMA Array Operations Site. Here the 66 ALMA antennas can ...

11 avril 2011: Cette photo panoramique montre le siège social de l'Observatoire européen austral à Garching, près de Munich, Allemagne. Cette image montre la vue du toit du bâtiment principal juste après le coucher du Soleil. Ceci est le centre scientifique, technique et administratif des opérations de l'ESO, c'est d'ici que les astronomes conduisent leurs recherches. Les scientifiques, techniciens et membres de l'administration travaillant d'ici viennent de partout mais tous ont un point commun: la passion pour l'astronomie. L'ESO est la principale organisation astronomique intergouvernementale en Europe et est l'observatoire astronomique le plus productif du monde. l'ESO exploite des télescopes à trois différentes sites d'observation au Chili: La Silla, Paranal et Chajnantor. De plus, Cerro Armazones, près de Paranal a été choisi comme site pour le Télescope Géant Européen (E-ELT). L'ESO propose des installations de recherche aux astronomes et est supporté par l'Autriche, la Belgique, le Brésil, la République tchèque, le Danemark, la ...

4 avril 2011: Deep in the Chilean Atacama Desert, far from sources of light pollution and other people-related disturbances, there is a tranquil sky like few others on Earth. This is the site for the European Southern Observatory's Very Large Telescope, a scientific machine at the cutting-edge of technology. In this panoramic photograph, the Large and Small Magellanic Clouds — satellite galaxies of our own — glow brightly on the left, while the VLT’s Unit Telescope 1 stands vigil on the right. Appearing to bridge the gap between them is the Milky Way, the plane of our own galaxy. The seemingly countless stars give a sense of the true scale of the cosmos. Every night ESO astronomers rise to the challenge of studying this vista to make sense of the Universe. This awe-inspiring image was taken by ESO Photo Ambassador Yuri Beletsky. Born in Belarus, Yuri now lives in Chile where he works ...

28 mars 2011: When completed, the antennas of the Atacama Large Millimeter/submillimeter Array (ALMA) will be spread across the Chajnantor plateau in the Chilean Andes over distances of up to 16 kilometres, but they will work in unison, to form what is known as an interferometer. In doing so, ALMA will be more powerful than the sum of its parts, acting like a single giant telescope as large as the whole collection of antennas. The 66 ALMA antennas are not all the same. A main array of fifty antennas with 12-metre dishes will be complemented by the Atacama Compact Array (ACA) of twelve smaller 7-metre dishes and four additional 12-metre dishes. The ACA dishes are being constructed by Mitsubishi Electric Corporation (MELCO). Three of them are shown in this photograph of the MELCO Site Erection Facility at the ALMA Operations Support Facility (OSF) site. The OSF is at an altitude of 2900 metres, ...

21 mars 2011: The night of 19 March saw an unusual coincidence of astronomical events: the full Moon occurred at almost exactly the same time as the Moon was closest to Earth in its elliptical orbit (the point called perigee). The combination of the Moon being both full and relatively close to the Earth made it look significantly bigger and brighter than usual. This panoramic photograph, taken by ESO Photo Ambassador Gerd Hüdepohl, captures this so-called "supermoon" as seen from Cerro Paranal, home of ESO's Very Large Telescope (VLT).On the right, in the east, the Moon rises over the mountains, while the setting Sun is visible on the left of the panorama, sinking in the west below the clouds over the Pacific Ocean. Its last rays illuminate the four giant VLT Unit Telescope buildings, the smaller VLT Survey Telescope building, the four round VLT Auxiliary Telescope enclosures, and the Paranal staff who have ...

14 mars 2011: The number of antennas for the Atacama Large Millimeter/submillimeter Array (ALMA) on the Chajnantor plateau has now reached double digits! The tenth antenna was moved up from the Operations Support Facility at an altitude of 2900 metres to the Array Operations Site at 5000 metres, high in the Chilean Andes, on 4 March 2011 using one of the ALMA transporter vehicles. ALMA is a telescope designed to observe millimetre- and submillimetre-wavelength light with its array of antenna dishes. Using a technique called interferometry, ALMA acts like a single giant telescope as large as the whole set of antennas. Thanks to the transporter vehicles, the antennas can be arranged in different configurations, where the maximum separation between them varies from 150 metres to 16 kilometres. The distant viewpoint of this photograph is necessary for one to see all ten of the antennas in a single shot. Nine of them, including the ...

7 mars 2011: The Atacama Large Millimeter/submillimeter Array (ALMA) antennas may look rooted to the ground in this striking image — taken at the Array Operations Site on the Chajnantor plateau, at an altitude of 5000 metres — but these dishes are surprisingly mobile. Thanks to the two antenna transporter vehicles, the antennas in the array — which will consist of a total of 66 dishes when construction is complete — can be repositioned to meet the needs of a particular observation project. The transporters, named Otto and Lore, were specially designed to transport the hefty 115-tonne antennas and position them precisely on concrete foundation pads, spread across the plateau over distances of up to 16 kilometres. Here, four antennas have been placed on closely spaced pads for testing during the Commissioning and Science Verification phase of ALMA construction. The transporter vehicles drive on 28 tyres, with two 700-HP (500 kW) diesel engines ...

28 février 2011: ALMA antennas stand side by side, built strong to withstand the unforgiving environment of the Chajnantor plateau, high in the Chilean Andes. At an altitude of 5000 m, the ALMA dishes — a total of 66 when construction is completed — will face strong winds and harsh sunlight, all without the safe haven of a protective dome. The temperature can vary by 40 degrees Celsius, dipping well below freezing and occasionally allowing snow to fall, as can be seen dusting the landscape in the background of this photograph. The ALMA project is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ESO is the European partner in ALMA. This photograph was taken by ESO Photo Ambassador José Francisco Salgado. Links ESO Photo Ambassadors webpage.

21 février 2011: Quatre antennes du Atacama Large Millimeter/submillimeter Array (ALMA) regardent ver le ciel nocturne étoilé en anticipation pour le travail qui se trouve devant soi. La Lune éclaire la scène sur la droite, tandis que la bande de la Voie Lactée s'étire en haut à gauche. ALMA est en train d'être construit à une altitude de 5000 mètres sur le plateau de Chajnantor dans le désert d'Atacama au Chili. C'est l'un des endroits le plus sec sur Terre, et cette sécheresse, combinée avec la fine atmosphère de haute altitude offre de superbes conditions pour observer l'Univers dans des longueurs d'onde du millimétrique et du sub-millimétrique. À ces longueurs d'onde, les astronomes peuvent regarder dans les nuages moléculaires qui sont des régions très denses de gaz et de poussière où de nouvelles étoiles naissent lorsque un nuage s'effondre sous sa propre gravité. Pour l'instant, l'Univers reste relativement inexploré dans les longueurs d'ondes ...

14 février 2011: This rich scattering of galaxies was captured using the Wide Field Imager attached to the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile. The thousands of galaxies contained in this small area of sky give a glimpse into the Universe’s distant past, whilst also acting as a powerful reminder of the immense scale of the cosmos. This image was taken as part of the COMBO-17 project (Classifying Objects by Medium-Band Observations in 17 Filters), in which detailed surveys of five small patches of sky were made through 17 different coloured filters. The area of sky covered by each of the five regions is about the same area as that covered by the full Moon. The survey has produced a remarkable haul of celestial specimens. For example, across just three of these regions over 25 000 galaxies have been identified. Just below the bright stars in the centre of ...

7 février 2011: The HAWK-I instrument on ESO's Very Large Telescope (VLT) at the Paranal Observatory in Chile has been used to great effect in producing this distinctive image of the distant galaxy NGC 157. Boasting a central sweep of stars resembling a giant "S", reminiscent of the comic book hero Superman’s symbol, this celestial spiral is indeed a super example of how new technology is helping us to learn more about the cosmos. HAWK-I stands for High-Acuity Wide-field K-band Imager, and it is one of the latest and most powerful instruments on the VLT. It detects infrared light, allowing us to peer through the gas and dust that normally obscures our view. This reveals an otherwise hidden view of the Universe, and gives astronomers the opportunity to study dense areas of star formation. Learning more about star formation is an important step towards expanding our understanding of our own origins. The same ...

31 janvier 2011: What looks like a barren and inhospitable alien landscape in this 360-degree panorama is in fact the site for ESO’s European Extremely Large Telescope, or E-ELT for short. When construction begins the uninhabited mountaintop left of the centre will become a hive of activity as engineers, technicians and scientists work on building the world’s biggest eye on the sky. In many ways Chile’s Cerro Armazones may seem like an alien world. The environment is harsh, with low humidity and air pressure, a blazing Sun during the day, but breathtaking skies at night. Cerro Armazones is in the Atacama Desert — one of the driest places on Earth. These conditions, combined with its remoteness, are what make the region such an excellent location for telescopes. Armazones is an isolated peak, 3046 metres above sea level. It is about 20 km away from Cerro Paranal, home of ESO's famous Very Large Telescope. ...

24 janvier 2011: As the Sun sets over Cerro Armazones, plans are well advanced for building the world's biggest “eye on the sky”: ESO's European Extremely Large Telescope (E-ELT). With a primary mirror 39 metres in diameter, the E-ELT will dwarf all existing visible-light telescopes. Site selection has been a vital part of the plans for the E-ELT. Over the course of several years a team of experts investigated locations around the world, looking for the best place to host such an ambitious project. The site for the E-ELT must be remote enough not to be influenced by problems such as light pollution, but also needs the necessary infrastructure for the construction and operation of the observatory, and to accommodate the over 150 staff who will eventually work there. Monitoring stations, such as the one shown here, were set up to test site conditions scientifically by measuring parameters that included atmospheric turbulence and ...