Photo de la semaine 2014

24 mars 2014: Les observatoires de l'ESO sont des lieux privilégiés où les astrophotographes peuvent saisir des vues étonnantes du cosmos. Mais ce n'est pas tout : parfois, ce sont des lieux idéaux pour capturer des images d'autres mondes sur notre propre planète également. Sur cette photo, Gabriel Brammer, ambassadeur photo de l'ESO, a utilisé un objectif fish-eye pour créer ce spectaculaire effet de ronde. Le ciel clair au-dessus de Paranal ressemble à une boule de verre remplie d'étoiles, la plate-forme du Very Large Telescope (VLT) encadrant la photo. En bas à gauche, les quatre télescopes de l'unité VLT, chacun d'une hauteur de 25 mètres, observent le ciel nocturne, l'un d'eux pointant son laser vers le haut dans la nuit. Dispersés dans le coin supérieur gauche du cadre, les dômes ronds des télescopes auxiliaires du VLT sont facilement repérables sous la brillante Voie lactée. Les deux taches floues juste au-dessus du laser sont ...

17 mars 2014: Another clear night at ESO’s Paranal Observatory in Chile — perfect for sitting back and taking in the sight of our galaxy, the Milky Way. Many of us living in living in crowded, light-polluted cities no longer get to see our cosmic home in such detail. We now know this stunning view to be our home galaxy, but the Ancient Greeks thought that it was the work of the Gods. Their legends told that this cloudy streak across the sky was really the breast milk of Hera, wife of Zeus. The Ancient Greeks are also to thank for the name “Milky Way”. The Hellenistic phrase Γαλαξίας κύκλος, pronounced galaxias kyklos, means “milky circle”, and provides the root for our modern name. This 360 degree panorama image was taken by ESO Photo Ambassador Gabriel Brammer. An astronomer visiting Paranal can be seen standing towards the right hand side of this image ...

10 mars 2014: On 20 January 2014, ESA's Rosetta spacecraft emerged from a long deep-space hibernation to approach its target — comet 67P/Churyumov-Gerasimenko (67P/CG). From our vantage point on Earth, comet 67P/CG has only just reappeared from behind the Sun. On 28 February 2014 ESO's Very Large Telescope (VLT) directed its gaze towards the comet as soon as it became visible from ESO's Paranal Observatory in Chile. ESO is collaborating with ESA to monitor the comet from the ground as it is approached by Rosetta over the coming months. These observations will prepare for the spacecraft's major rendezvous with the comet, planned for August of this year (see potw1403a). This new image, and many more to come, will be used by ESA to refine Rosetta's navigation, and to monitor how much dust the comet is releasing. The image on the left was created by stacking the individual exposures to show the background stars ...

3 mars 2014: High on the Chajnantor Plateau in the Chilean Andes lies the Atacama Large Millimeter/submillimeter Array (ALMA), an observatory surrounded by large expanses of dry landscape. Perhaps surprisingly, the region is home to a number of different wildlife species, many of which occasionally pop up near to the observatory. Further south, ESO’s La Silla Observatory recently had visits from a South American grey fox (potw1406a), and wild horses (potw1344a). The most recent cute visitor to ALMA is this vicuña fawn, found on 16 February 2014 by ALMA workers. The fawn was only a few weeks old, weakened after it was chased by foxes until it lost sight of its herd. After a couple of unsuccessful attempts the following day to return the fawn to its herd, the workers transferred it to the Wildlife Rescue and Rehabilitation Center at the Universidad de Antofagasta, where it is being treated so that it can ...

24 février 2014: Bereft of colour in this striking infrared image, the sweeping curves of ESO's Headquarters clash with the frosty natural beauty of the surrounding trees. The extreme curvature visible in this image is due to the photographer's use of a fisheye lens, which distorts the view and causes the building to encircle the pale foliage and frame the sky above. The foliage appears to be bright as it reflects the infrared light, and the pale white hue comes from the photographer applying a white colour balance to the tree leaves. The precise curves of concrete, glass, and steel give clues as to the Headquarters building's peculiar structure. In 1981 an article in ESO's The Messenger described the ESO building as "a labyrinth of the kind used to test the intelligence of rats". But, fortunately for ESO, the writer soon noted that "human beings are on average cleverer than rats, and the ...

17 février 2014: These new images from ESO's Very Large Telescope Survey Telescope (VST) show ESA's Gaia spacecraft in its position some 1.5 million kilometres beyond Earth's orbit. Launched on the morning of Thursday, 19 December 2013, the satellite is on a quest to build a 3D map of our galaxy over the next five years. Mapping the sky has been one of humanity's quests since the dawn of time, and Gaia will take our understanding of our stellar neighbourhood to a whole new level. It will measure very precisely the positions and motions of about one billion stars in our galaxy, to explore the Milky Way's composition, formation and evolution. These new observations are the result of a close collaboration between ESA and ESO to monitor the spacecraft from the ground. Gaia is the most accurate astrometric device ever built, but in order for its observations to be useful it needs to ...

10 février 2014: Perched precariously on the edge of the habitable world, life manages to cling on. On the outskirts of the hot, dry Atacama Desert, this hardy South American grey fox has just awoken, stretching leisurely. These foxes are generally active during the night, making the most of the drop in temperature that comes with a respite from the hot Chilean Sun. In the background there are other signs of life. This white dome houses the Swiss 1.2-metre Leonhard Euler Telescope, which is protected from the harsh conditions by its outer shell. As the skies grow darker at ESO’s La Silla Observatory another famously nocturnal species, the astronomer, wakes up, stretches, and gets ready to scan the skies with buzzing and whirring technology. This image was taken by ESO Photo Ambassador Malte Tewes and submitted to the Your ESO Pictures Flickr group. The Flickr group is regularly reviewed and the best photos ...

3 février 2014: This beautiful panorama of ESO's Paranal Observatory was taken on 5 July 2012, and marks one of the driest days ever recorded at the Very Large Telescope complex. Paranal sits like an island in the middle of the frame, with massive cloud banks floating below, over the distant Pacific Ocean. The extremely low humidity at Paranal during this period was recorded by a water vapour radiometer known as LHATPRO, which monitors the atmosphere to support the observations carried out at the observatory [1]. Meteorologists from two Chilean universities identified the cause for these unusually dry conditions: high-altitude Antarctic air moving far to the north, and descending over Paranal. This cold front lingered around Paranal for over 12 hours, causing a record-low level of humidity in the air above the observatory [2]. Florian Kerber (ESO) and colleagues analysed this unusual weather, publishing the results in a paper in the Monthly Notices ...

27 janvier 2014: Astronomers do not always swim at the swimming pool at the Paranal Observatory Residencia, but when they do, they like to show how physical principles work. In this picture the French ESO astronomer Jean-Baptiste Le Bouquin is demonstrating how waves — not light waves, but water waves — can combine, or interfere, to create larger waves. The combination of light waves is the main principle behind the VLT Interferometer: the light waves captured by each one of the four 8-metre telescopes are combined using a network of channels and mirrors. This way the spatial resolution of the telescope is vastly increased and, with enough exposure time, the cameras and instruments can reveal the same level of detail as a telescope with a 130-metre diameter mirror could, far bigger than any telescope in existence. This image was taken by award-winning editorial and commercial photographer Max Alexander. See also Tribute to ESO’s ...

20 janvier 2014: ESA's Rosetta spacecraft will wake up today, 20 January, after 31 months in deep space hibernation, to finally close in on comet 67P/Churyumov-Gerasimenko (67P/CG). This image shows the most recent observations of the 4-kilometre diameter comet, taken on 5 October 2013 by ESO's Very Large Telescope (VLT) when the comet was around 500 million kilometres away — before it passed behind the Sun and out of view from Earth's perspective. For this image, a long series of observations was processed to reveal both the comet without the background stars (on the left panel), and the star field with the track of the comet marked (on the right). Viewed against a crowded star field towards the centre of the Milky Way, the comet was still so far from the Sun that the icy nucleus was not releasing any gas or dust, and appears as a simple spot. As it approaches the ...

13 janvier 2014: Thanks to ESO’s Photo Ambassadors we can enjoy sensational images taken at the ESO sites on the remote mountaintops of Chile. Babak Tafreshi has captured this fine panoramic view of the antennas of the Atacama Large Millimeter/submillimeter Array (ALMA) at twilight. Resembling a frame from a science fiction movie, the technological spectacle of ALMA against the raw natural power of the landscape on the Chajnantor Plateau, 5000 metres above sea level, results in fascinating images like this one. There are a few details you shouldn't miss in this panoramic photo of ALMA (seen more clearly in the zoomable version), all lying between the two groups of antennas: the "Earth's shadow" and "Belt of Venus" phenomena, visible as the dark blue and light pink bands stretching across the sky, and the planet Jupiter, seen right above the mountain in the background. ALMA, an international astronomy facility, is a partnership of Europe, ...

6 janvier 2014: Admirez le ciel nocturne depuis l'observatoire Paranal de l'ESO au Chili, et vous serez accueillis par une vue époustouflante comme celle-ci. Des taches de bleu, d'orange, de rouge, chacune étant une étoile, une galaxie ou une nébuleuse différente, ou plus, formant ensemble un ciel étincelant. Les astronomes observent cette magnifique toile de fond et tentent de percer les mystères de l'Univers. Pour ce faire, ils utilisent des télescopes comme ceux qui sont montrés ici, les télescopes auxiliaires VLT. Cette image montre trois des quatre unités mobiles qui alimentent en lumière le Very Large Telescope Interferometer, l'instrument optique le plus avancé au monde. En se combinant pour former un plus grand télescope, elles sont plus grandes que la somme de leurs parties : elles révèlent des détails qui seraient visibles avec un télescope aussi grand que la distance qui les sépare.