Picture of the Week 2016

8 August 2016: Illuminated only by the impressive nighttime sky, one of ESO’s Very Large Telescope (VLT) Unit Telescopes is an imposing feature in this Picture of the Week. The VLT is one of the largest and most sophisticated astronomical installations in the world. It consists of four identical Unit Telescopes, each with a main mirror of 8.2 metres in diameter. While each is a large telescope in its own right, by combining the light from all telescopes on the platform — a configuration known as an interferometer — the array in its longest baseline can resolve celestial objects 25 times finer than is possible by using one of the telescopes on its own. The VLT is situated 2635 metres above sea level in Chile’s Atacama Desert, where the amount of water vapour in the atmosphere is low enough to permit the VLT to observe infrared, as well as visible, light. The spectacular ...

1 August 2016: Science and art unite in this beautiful photograph, taken in Chile’s Atacama Desert by ESO Photo Ambassador Adhemar M. Duro Jr. To create this visual masterpiece Adhemar pointed his camera at the sky’s south pole, the point at the centre of all the bright arcs and circles. All the stars in the night sky revolve around this point. Over a period of several hours, this motion creates star trails, with each individual star tracing out a circle on the sky. These trails display the various brightnesses and colours of each star, creating a captivating scene! Towards the top left of the image, you can see a short, bright streak of light cutting across the trails — this is caused by a meteor, burning up in a flash of light as it enters Earth’s atmosphere. The desert’s harsh and arid landscape, illuminated here by the light from the stars themselves, is ...

25 July 2016: Each of the thousands of spots in this new image represents a distant star, and the glittering blue holes reveal glimpses of our neighbouring galaxies, the Large and Small Magellanic Clouds. Although this image looks as if it was made on a large scale telescope it was in fact captured from ESO’s La Silla Observatory using a portable setup consisting of a SBIG STL-11000M CCD camera and a Canon prime lens. It was presented in a scientific paper alongside state-of-the art simulations, in an exciting example of how a small camera, a fast lens, a long exposure time and one of the world’s best astronomical sites can reveal huge faint features better than even a big telescope. This deep image was captured using the LRGB method, and provides an insight into the actual process of creating spectacular astrophotography. Many challenges face those attempting to photograph the night sky, including interference ...

18 July 2016: In this image we see a rare sight — water in the Atacama Desert! Reflected on the water’s calm surface we can see the familiar sight of Cerro Paranal, home to ESO’s Paranal Observatory. This desert is one of the driest and most inhospitable places on Earth. The average rainfall in the Cerro Paranal region is less than 10 millimetres per year, indicating that this photograph was taken just after a period of rare rainfall in the area. Soon after the image was taken, the temporary lagoon evaporated swiftly, leaving the valley floor as dry and desiccated as ever. However, what is arguably bad for the minimal flora and fauna of the region is excellent for astronomers. The lack of rainclouds and the dry air allow Paranal astronomers to observe all year round. With over 300 clear nights per year, the Atacama Desert is one of the best sites in ...

11 July 2016: This stunning ultra high definition panorama, taken by ESO Photo Ambassador Petr Horálek, shows the Milky Way galaxy arching above ESO’s La Silla Observatory in Chile. La Silla is located at the southern edge of the Atacama Desert, from where the observatory’s numerous telescopes observe the night sky — one of the darkest on the Earth — perched 2400 metres above sea level, and so making the most of the unrivalled atmospheric conditions at the site to reveal the cosmos in remarkable detail. This image is certainly no different! Our galaxy’s cloudy and dusty structure appears as a brilliant and glowing coronet above the open dome of the MPG/ESO 2.2-metre telescope, which appears to be gobbling up the bright smudge of the Large Magellanic Cloud. Various clouds and nebulae, including the well-known Gum Nebula, stand out against the dark sky in the central–upper part of the image, shining in a ...

4 July 2016: To take this Picture of the Week, ESO Photo Ambassador Adhemar Duro stopped by the roadside en route to one of ESO’s observing sites in Chile. This road winds up to the Atacama Large Millimeter/submillimeter Array, ALMA, located at an altitude of 5000 metres. Due to the image’s long exposure time, the stars trace out circles on the night sky as they orbit the southern celestial pole, located at the centre of the image. Atop the celestial pole the Small and Large Magellanic Clouds — two satellite galaxies of the Milky Way, visible only in the southern hemisphere — can be seen as diffuse bluish clouds. On the left side of the image, an area densely populated by stars marks the centre of the Milky Way. Even though the image was taken in the remote Atacama Desert, the distant lights of the small town San Pedro de Atacama are visible ...

27 June 2016: This image transports you to the most advanced visible-light astronomical observatory in the world: the Very Large Telescope (VLT), located at ESO’s Paranal Observatory in Chile. The shadowy figure gazing at the dark skies is photographer Babak Tafreshi, as captured by his fellow ESO Photo Ambassador Petr Horálek. For a moment, place yourself in Babak’s — or indeed Petr’s — shoes. Here, you are king of the cosmos. The site is silent, dark, still. You stare up at the pristine Chilean night sky, which, with its extremely low levels of both light pollution and water vapour, offers spectacular nighttime scenery to delight any astrophotographer or stargazer. With your trusty camera on hand, a night of amazing photo opportunities lies ahead; you anticipate spending clear hour after clear hour documenting the heavens, with no fear of cloudy weather appearing, uninvited, to spoil the view. The Large Magellanic Cloud is visible at ...

20 June 2016: This Picture of the Week illustrates the remarkable capabilities of SPHERE (the Spectro-Polarimetric High-contrast Exoplanet REsearch instrument), a planet-hunting instrument mounted on ESO’s Very Large Telescope (VLT) in Chile: It shows a series of broken rings of dust around a nearby star. These concentric rings are located in the inner region of the debris disc surrounding a young star named HD 141569A, which sits some 370 light-years away from us. In this image we see what is known as a transition disc, a short-lived stage between the protoplanetary phase, when planets have not yet formed, and a later time when planets have coalesced, leaving the disc populated only by any remaining — and predominantly dusty — debris. What we see here are structures formed of dust, revealed for the first time in near-infrared light by SPHERE — at a high enough resolution to capture remarkable detail! The area shown in ...

13 June 2016: Astronomers hunt for planets orbiting other stars (exoplanets) using a variety of methods. One successful method is direct imaging; this is particularly effective for planets on wide orbits around young stars, because the light from the planet is not overwhelmed by light from the host star and is thus easier to spot. This image demonstrates this technique. It shows a T-Tauri star named CVSO 30, located approximately 1200 light-years away from Earth in the 25 Orionis group (slightly northwest of Orion’s famous Belt). In 2012, astronomers found that CVSO 30 hosted one exoplanet (CVSO 30b) using a detection method known as transit photometry, where the light from a star observably dips as a planet travels in front of it. Now, astronomers have gone back to look at the system using a number of telescopes. The study combines observations obtained with the ESO’s Very Large Telescope (VLT) in Chile, the W. ...

6 June 2016: In this picture, the enclosure for ESO’s New Technology Telescope (NTT) has opened its angled doors to reveal a long slice of the southern sky. The sky is freckled by stars, while the moon lights up the inner walls of the NTT dome, casting a shadow over the 3.6-metre telescope. At the top of the telescope we can make out the secondary mirror cell of the telescope, held in a ring structure and supported on struts above the primary mirror. One of the NTT’s remarkable aspects is that it employs active optics, in which the primary mirror is flexible and its shape is actively adjusted during observations by actuators to preserve the optimal image quality. The position of the secondary mirror is also actively controlled in three directions. This technology, developed by ESO, is nowadays applied to all major modern telescopes, such as the Very Large Telescope at Cerro Paranal ...

30 May 2016: High upon the Chajnantor Plateau, a solitary vicuña — a relative of llamas, alpacas and camels — stands before the APEX antenna. Both the animal and the antenna are well-equipped to handle the harshness of their remote and arid environment. At Chajnantor, some 5000 metres above sea level, temperatures can get fairly warm during the day, thanks to the intense sunlight beaming through the thin atmosphere. However, at night, the mercury plunges. Engineers built the antenna of APEX to withstand the harsh weather, carefully crafting them to endure relentless sunlight, strong winds, and severe temperature changes ranging from +20 to -20 degrees Celsius. The hardy vicuña, meanwhile, with its thick, wooly coat that traps hot air close to its body, can also handle nature’s quirks. The species, only found at high altitudes in the Andes Mountains, grazes on the tough grasses found across the otherwise barren slopes. Although the Chajnantor ...

23 May 2016: Using 39 of the 66 antennas of the Atacama Large Millimeter/submillimeter Array (ALMA), located 5000 metres up on the Chajnantor plateau in the Chilean Andes, astronomers have been able to detect carbon monoxide (CO) in the disc of debris around an F-type star. Although carbon monoxide is the second most common molecule in the interstellar medium, after molecular hydrogen, this is the first time that CO has been detected around a star of this type. The star, named HD 181327, is a member of the Beta Pictoris moving group, located almost 170 light-years from Earth. Until now, the presence of CO has been detected only around a few A-type stars, substantially more massive and luminous than HD 181327. Using the superb spatial resolution and sensitivity offered by the ALMA observatory astronomers were now able to capture this stunning ring of smoke and map the density of the CO within the ...

16 May 2016: On 16 March the names of the eight participants of #MeetESO — ESO’s first social media gathering — were announced, one month after the campaign’s launch. On 7 May 2016, the participants winged their way to Chile for a five-day visit to some of the most exciting astronomical facilities in the world: the Very Large Telescope (VLT) — the world's most advanced visible-light astronomical observatory — and the Atacama Large Millimeter/submillimeter Array (ALMA), the largest ground-based astronomical project in existence. As shown by their big smiles, the #MeetESO travellers fully enjoyed the packed itinerary, from engaging with ESO and ALMA staff during their night-time observations at one of the best locations on Earth, to staying at ESO’s Residencia, which acts as a hotel for working astronomers (but may be more familiar to many as the building that was “blown up” in the James Bond movie Quantum of Solace). The climax ...

9 May 2016: This Picture of the Week shows the Vela ring galaxy, visible as a bright core surrounded by a baby blue halo. This ring galaxy — located in the southern constellation of Antlia (The Pump) — is notable due to its compact core and large circular belt of gas and stars. It is thought that ring galaxies like this are created when larger galaxies are punctured by a smaller galactic aggressor, which, passing through the heart of its more sizeable victim, triggers a shock wave that spreads outwards. This pushes gas to the galaxy’s periphery, where it begins to collapse and form new stars. The Vela ring galaxy is unusual in that it actually exhibits at least two rings, suggesting that the collision was not a recent one. This picture also features a galaxy known as ESO 316-33, seen just above and to the left of the Vela ring galaxy, and ...

2 May 2016: Glistening against the awesome backdrop of the night sky above ESO’s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 (UT4) of the Very Large Telescope (VLT); they mark the first use of multiple lasers at ESO and they are the most powerful laser guide stars ever used in astronomy. Some 90 kilometres up in the atmosphere, the lasers excite atoms of sodium, creating artificial stars for the telescope’s adaptive optics systems. Modern telescopes use adaptive optics systems to compensate for the blurring effect of the Earth’s atmosphere. To do this, the telescope needs to be able to see a bright reference star while it is observing its main target. However, there is not always a suitably bright star nearby, so astronomers use lasers to create artificial stars exactly where they need them. Sodium atoms high in the atmosphere are made to glow by the ...

25 April 2016: Astronomers have discovered a new satellite orbiting the main belt asteroid (130) Elektra — the smallest object visible in this image. The team, led by Bin Yang (ESO, Santiago, Chile), imaged it using the extreme adaptive optics instrument, SPHERE, installed on the Unit Telescope 3 of ESO’s Very Large Telescope at Cerro Paranal, Chile. This new, second moonlet of (130) Elektra is about 2 kilometres across and has been provisionally named S/2014 (130) 1, making (130) Elektra a triple system. Exploiting the unprecedented sensitivity and spatial resolution of the instrument SPHERE, the team also observed another triple asteroid system in the main belt, (93) Minerva. Asteroids are the relics of the building blocks that formed the terrestrial planets in the early days of the Solar System. Studying asteroids with multiple satellites is of crucial importance because their formation mechanisms can provide information about planet formation and evolution that cannot be ...

18 April 2016: As the Sun raises at Cerro Paranal, in Chile, filling the sky with superb orange shades, two members of the ESO Fulldome Expedition, Babak Tafreshi (left) and Yuri Beletsky (right), are preparing their tripods and cameras for the day ahead. Above the silhouette of the Chilean mountains, the gentle smile of a crescent Moon and the bright planet Venus strike a pose for the cameras. Thanks to a phenomenon called earthshine, the entire disc of the Moon can be seen shining in light reflected off the Earth. The telescope in silhouette in front is an Auxiliary Telescope (AT), part of Very Large Telescope (VLT) at ESO's Paranal Observatory. This twilight moment was captured by ESO Photo Ambassador Petr Horálek, while participating in the ESO Fulldome Expedition which is gathering spectacular images for use in the ESO Supernova Planetarium & Visitor Centre, currently under construction at ESO’s Headquarters in Garching (near ...

11 April 2016: This Auxiliary Telescope at the Very Large Telescope (VLT), located at the Paranal Observatory in Chile, looks to be pointing at the greenish emerald glow of the comet 252P/LINEAR high above it. Discovered in April 2000, 252P/LINEAR is a relative newcomer to the inner Solar System, traveling between the orbit of Jupiter and the orbit of Earth. A couple of days ago, in March 2016, it passed particularly close to the Earth, at a distance of only 5.2 millions kilometers, ranking as the fifth closest recorded passage of a comet. It can still be admired in the southern hemisphere. The green colour arises from fluorescing carbon-based gas surrounding the comet. This gem of a picture was taken by the ESO Photo Ambassador Babak A. Tafreshi. He has just started out on ESO’s Fulldome Expedition, during which he will be taking more spectacular pictures from ESO’s observatories and of the southern ...

4 April 2016: The faint light extending up from the horizon just below centre of this photo is known as zodiacal light, caused by sunlight scattering from cosmic dust in the plane of our Earth’s orbit. A second band of light can be seen at the horizon on the lower left. This red light is airglow, produced by the Earth’s atmosphere. Airglow is caused by processes taking place in the upper atmosphere, including cosmic rays, recombining photoionized atoms, and various chemical reactions between oxygen, nitrogen, hydroxyl, sodium, and lithium atoms. The third and final band is the Milky Way, our home galaxy, high in the sky. This band consists of billions of stars of all kinds. Many of them are hidden to the human eye behind large layers of interstellar dust, giving the Milky Way its characteristically mottled look. At the centre of the image stands ESO Photo ambassador Babak Tafreshi, watching the ...

28 March 2016: Deep in the Chilean Desert, astronomers staying at ESO’s Residencia, the VLT Observatory's hotel, witness a skyscape like few others on Earth. Designed by the German architects Auer+Weber+Assoziierte, the Residencia provides an oasis for those working at ESO’s Paranal Observatory. The Atacama Desert is one of the harshest landscapes imaginable. Extreme dryness, intense ultraviolet radiation from the Sun, and high altitude are a normal part of everyday life. However, come nightfall, the Residencia experiences some of the best observing conditions in the world. Residencia and ESO’s Very Large Telescope (VLT) — housed at the Paranal Observatory — are far from sources of light pollution, and experience exceptionally clear atmospheric conditions. On moonless nights, the sky can be so clear and dark that light from the Milky Way casts a shadow on the ground! These factors permit high quality scientific observations to be made as well as offering amazing conditions for ...