Picture of the Week 2010

9 August 2010

Frenzied Star Birth in Haro 11

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 produce stars at a frantic rate, converting about 20 solar masses of gas into stars every year.

Haro galaxies, first discovered by the noted astronomer Guillermo Haro in 1956, are defined by unusually intense blue and violet light. Usually this high energy radiation comes from the presence of many newborn stars or an active galactic nucleus. Haro 11 is about 300 million light-years away and is the second closest of such starburst galaxies.

The paper describing this result (“Super star clusters in Haro 11: Properties of a very young starburst and evidence for a near-infrared flux excess”, by A. Adamo et al.) is available at http://adsabs.harvard.edu/doi/10.1111/j.1365-2966.2010.16983.x

2 August 2010

Exoplanet Hunters at La Silla*

In the search for distant worlds, few telescopes have had as much success as ESO's 3.6-metre telescope and the Swiss 1.2-metre Leonhard Euler Telescope, both of which are shown in this image.

The 3.6-metre telescope is home to HARPS (High Accuracy Radial velocity Planet Searcher), a spectrograph with unrivalled precision, and holder of many records in the field of exoplanet research, including the discovery of the least massive exoplanet, as well as of the smallest ever measured. Together with HARPS, the Leonhard Euler Telescope has allowed astronomers to find that six exoplanets from a larger sample of 27 were orbiting in the opposite direction to the rotation of their host star — providing an unexpected and serious challenge to current theories of planet formation.

At 2400 metres above sea level in the southern part of Chile’s Atacama Desert, La Silla was ESO’s first observation site. Along with the 3.6-metre telescope, it also hosts the New Technology Telescope (NTT) and the MPG/ESO 2.2-metre telescope as well as several national and smaller telescopes.

26 July 2010

Arp 22 Stretches Out

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 oxygen).

19 July 2010

A European ALMA antenna takes a ride on a transporter

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 new locations.

The European ALMA antennas are provided by ESO, through a contract with the AEM Consortium (Thales Alenia Space, European Industrial Engineering, and MT-Aerospace). The ALMA antenna transporters are also provided by ESO, and manufactured by the company Scheuerle Fahrzeugfabrik GmbH. ALMA, an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile.


12 July 2010

Partial Solar Eclipse over the VLT

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 filter is held by hand between the camera lens and the Sun, and lets us see the definite bite-mark on the left of the Sun. Around it is the dramatic location of Paranal's Very Large Telescope.

In addition to the ESO staff watching the partial eclipse over Paranal, a small group of enthusiastic science photographers from ESO, including members of the ESO education and Public Outreach Department, spent their vacation at Easter Island to witness the total eclipse. Among them was ESO Photo Ambassador Stéphane Guisard.


5 July 2010

Building the E-ELT

This series of artist’s impressions shows some of the main phases in the early stages of construction of the European Extremely Large Telescope (E-ELT), assuming the final go-ahead is given at the end of 2010. The E-ELT is to be built on Cerro Armazones, a 3060-metre high mountain near ESO’s Paranal Observatory in Chile, and is planned to be operational early in the next decade.

With a primary mirror 39 metres across, far larger than any visible light telescope currently in operation, the E-ELT will be “the world’s biggest eye on the sky”. This will give it an unparalleled power to see faint and distant objects in the sky.

The E-ELT will tackle the biggest scientific challenges of our time, and aim for a number of notable firsts, including tracking down Earth-like planets around other stars in the habitable zones where life could exist — one of the Holy Grails of modern observational astronomy. It will also perform “stellar archaeology” in nearby galaxies, as well as make fundamental contributions to cosmology by measuring the properties of the first stars and galaxies and probing the nature of dark matter and dark energy. On top of this astronomers are also planning for the unexpected — new and unforeseeable questions will surely arise from the new discoveries made with the E-ELT. The E-ELT may, eventually, revolutionise our perception of the Universe, much as Galileo’s telescope did, 400 years ago.

Erecting the E-ELT’s housing is a major engineering feat. Because of the size of the equipment inside, the moveable dome of the building has to be over 80 m high — about the height of the dome of St Paul’s Cathedral in London.

The design for the E-ELT shown here was published in 2010 and is preliminary.

More information about the E-ELT is available in the E-ELT web pages, the E-ELT Press Kit and the E-ELT FAQ.

28 June 2010

The Oddest Member of the Leo Triplet

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 consequence of the gravitational interaction between NGC 3628 and its bullying companions. This boxy or “peanut-shaped” bulge, seen as a faint X-shape, is formed mainly of young stars and gas and dust, which create the bulge away from the plane of the rest of the galaxy through their powerful motions. Because of its appearance, NGC 3628 was catalogued as Arp 317 in the Atlas of Peculiar Galaxies, published in 1966, which aimed to characterise a large sample of odd objects that fell outside the standard Hubble classification, to aid understanding of how galaxies evolve.

The depth of the image reveals a myriad of galaxies of different shapes and colours, some of which lie much further away than NGC 3628. Particularly noticeable is the fuzzy blob just in the centre of the image, which is a diffuse satellite galaxy. A number of globular clusters can be seen as fuzzy reddish spots in the halo of the galaxy. Also visible as bright spots near the lower edge of the image (the two blue star-like objects below the satellite galaxy) are two quasars, the central engines of distant and very energetic galaxies, billions of light-years away.

This image has been taken with the FORS2 instrument, attached to one of the ESO Very Large Telescope’s Unit Telescopes. It is a combination of exposures taken through different filters (B, V and R), for a total exposure time of just below one hour. The field of view is about 7 arcminutes across, which is why this large galaxy does not fit into the image.


21 June 2010

Celestial Tic-Tac-Toe: Mercury, Venus and the Moon Align

One morning, in March 2008, a rare and beautiful sight greeted Yuri Beletsky, astronomer at ESO’s Very Large Telescope (VLT) observatory at Paranal in northern Chile. In the sky above the observing deck, the planets Mercury and Venus were in alignment above the Moon, in a celestial event known as a conjunction.

Mercury, the smallest of the planets and shining highest in the sky in this image, orbits closest to the Sun of all the eight planets in our Solar System. Venus comes next, followed by Earth and its Moon. So this image captures the full stock of major astronomical bodies that pass between Earth and its host star.

To the bottom left, seen as an impressive silhouette, and accompanying this cosmic chance encounter, is one of the four 1.8-metre Auxiliary Telescopes (ATs) deployed at Paranal. These mobile telescopes are used for interferometry, an astronomical technique that essentially combines the observing power of all the telescopes involved into one giant telescope, allowing astronomers to probe the mysteries of the Universe in even greater detail.

14 June 2010

A Quintuplet of ALMA Antennas — And Then There Were Five

On the Chajnantor plateau, the Atacama Large Millimeter/submillimeter Array (ALMA) is growing. On 31 May 2010, the number of ALMA’s state-of-the-art antennas on the 5000-metre-altitude plateau in the Chilean Andes increased to five. This photograph shows the five 12-metre diameter antennas at the Array Operations Site, clustered on the closely spaced foundation pads of what will be ALMA’s “Atacama Compact Array”.

When complete, ALMA will have fifty-four 12-metre and twelve 7-metre diameter antennas, operating together as an interferometer: the signals from the individual antennas are combined in a specialised supercomputer — the ALMA correlator — so that the array of antennas acts as a single, giant telescope. The team of astronomers and engineers have now achieved a successful test linking all of these first five antennas together as an interferometer.

This result follows the successful first measurements with a pair of antennas in October 2009 (see ESO Announcement) and the linkup of three antennas in November (see ESO Press Release eso1001). These milestones have already demonstrated the excellent performance of the instruments, but the addition of yet more antennas represents a further step in ALMA’s growth, and has allowed the team to make some further tests of the correlator that were not possible with fewer antennas.

ALMA will probe the sky in millimetre and submillimetre wavelengths of light. This light comes from vast cold clouds in interstellar space, at temperatures only a few tens of degrees above absolute zero, and from some of the earliest and most distant galaxies in the Universe.

The team are now carrying out additional tests on the antennas, and over the course of the coming months more antennas will arrive on the high site. ALMA will start early scientific observations using a partial array of antennas around 2011, with construction to be completed around 2012.

ALMA, the largest astronomical project in existence, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ESO is the European partner in ALMA.

More info: ESO ALMA web pages

7 June 2010

Dramatic Moonset — Amazing Sight on Cerro Paranal, Home of ESO’s Very Large Telescope*

As the full Moon sets, the Sun is about to rise on the opposite horizon. The Very Large Telescope (VLT) has already closed its eyes after a long night of observations, and telescope operators and astronomers sleep while technicians, engineers and day astronomers wake up for a new day of work. Operations never stop at the most productive astronomical ground-based observatory in the world.

ESO staff member Gordon Gillet welcomed the new day by capturing this stunning image from 14 km away, on the road to the nearby Cerro Armazones, the peak recently chosen by the ESO Council as the preferred location for the planned 40-metre-class European Extremely Large Telescope (E-ELT).

Contrary to what one may think, this picture is no montage. The Moon appears large because it is seen close to the horizon and our perception is deceived by the proximity of references on the ground. In order to get this spectacular close view, a 500-mm lens was necessary. The very long focal length reduces the depth of field making the objects in focus appear as if they were at the same distance. This effect, combined with the extraordinary quality of this picture, gives the impression that the Moon lies on the VLT platform, just behind the telescopes, even though it is in fact about 30 000 times further away.

31 May 2010

The Blinking Galaxy

NGC 6118, a grand-design spiral galaxy, shines bright in this image, displaying its central bar and tight spiral arms from its home in the constellation of Serpens (The Snake). The galaxy is sometimes known to amateur astronomers as the “Blinking Galaxy” because this relatively faint, fuzzy object would appear to flick into existence when viewed through their telescopes in a certain orientation, and then suddenly disappear again as the eye position shifted. The brilliant blue star-forming regions of the galaxy, where hot young stars are born, are beautifully illuminated, even from over 80 million light-years away. In 2004, regular observers of this galaxy saw a “new star” appear near the edge of the galaxy (above the centre of the image). Far from being a new star, this object, supernova 2004dk, is in fact the final, powerful burst of light emitted by the explosion of a star.

Though shy to lesser telescopes, the galaxy cannot hide from ESO’s Very Large Telescope (VLT) at Cerro Paranal, Chile. The image was obtained using the VIsible MultiObject Spectrograph (VIMOS) at the VLT.

24 May 2010

Building Connections with EVALSO

Alongside the B-710 road, between the Paranal airstrip and the turn-off to Cerro Armazones in the Chilean Atacama Desert, a crew is hard at work laying a fibre data cable. The cable will connect the observatories at Paranal (ESO) and Armazones (OCA) with the main scientific data backbone in South America, bridging the gap between these remote outposts and the scientific community thirsty for their data.

This new cable, laid down by ESO, is part of the EVALSO (Enabling Virtual Access to Latin-American Southern Observatories) project that aims to create an entire high-speed data infrastructure between these two astronomical sites in Chile and the rest of the scientific and academic community.

Once completed, the high-speed interconnectivity will be from the Santiago area,  via the main Chilean backbone along the Panamerican Highway, to the ESO site on Cerro Paranal, which houses the Very Large Telescope (VLT) and to Cerro Armazones, currently housing OCA and the baseline site for the planned 40-metre-class European Extremely Large Telescope (E-ELT).

EVALSO will make use of the infrastructure of REUNA (the Chilean academic network) and CLARA/ALICE (the Latin American academic networks interconnection) and will assume the transit of the data through the European federal research network infrastructure (DANTE/GEANT) and the European national research and education networks. A strong relationship with Latin American partners and the academic world is planned.

EVALSO is funded under the European Commission FP7 and is a partnership between Universita’ degli Studi di Trieste (I), ESO, Ruhr-Universitaet Bochum (D), Consortium GARR (Gestione Ampliamento Rete Ricerca) (I), Universiteit Leiden (NL), Istituto Nazionale di Astrofisica (I), Queen Mary and Westfield College University of London (UK), Cooperacion LatinoAmericana de Redes Avanzasas (CLARA) (U), and Red Universita Nacional (REUNA)(CL), .

17 May 2010

Great progress for the ALMA Santiago Central Office building

The Santiago Central Office building, the soon-to-be headquarters of the Atacama Large Millimeter/submillimeter Array (ALMA) project in the Vitacura district of the Chilean capital. The new building is rapidly approaching completion and is adjacent to ESO’s Santiago offices. It was built by ESO as part of its responsibilities as the European ALMA partner. The ALMA Santiago Central Office building covers nearly 7000 square metres, stands two storeys tall, and includes an underground parking area for 130 cars.

ALMA, the largest astronomical project in existence, is a revolutionary astronomical telescope, comprising an array of 66 giant 12-metre and 7-metre diameter antennas observing at millimetre and submillimetre wavelengths. The facility is currently under construction on the 5000-metre high Chajnantor plateau in the Chilean Andes. ALMA is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile.

10 May 2010

Snow Visits the ALMA Site*

High in the Chilean Andes, at 5000 metres above sea level, one of the giant Atacama Large Millimeter/submillimeter Array (ALMA) antenna transporters contemplates an unexpected sight — a delicate dusting of snow whitens the breathtaking landscape of the Chajnantor plateau, home of the ALMA project. Snow is a very rare event at this extremely arid site and is a consequence of the Altiplanic winter, caused when the jet stream reverses and comes from the chill east. Chajnantor is one of the driest sites in the world, making it excellent for astronomical observations. The hill in the background is Toco, a 5600-metre mountain toward the north. This image was taken on 30 April 2010.

The ALMA transporters, two giant custom-built vehicles, can move the antennas across the Chajnantor plateau, allowing different configurations of the array. Since late 2009, there have been three antennas at 5000 metres. Eventually ALMA will have a total of 66 antennas when complete, around 2012, and early scientific observations are expected around 2011.

This image is available as a mounted image in the ESOshop.

3 May 2010

Paranal’s Telescopes in the Distance

This picture looks like a scene from a science fiction movie, with strange, distant structures rising over a desolate alien valley. In fact, this is the barren Atacama Desert in northern Chile, and the oddly shaped buildings silhouetted against the sky are part of ESO’s Very Large Telescope (VLT) observatory, the world’s most advanced ground-based observatory. The four 8.2-metre Unit Telescopes stand out to the right on the summit of Mount Paranal. To the left looms the new 4.1-metre Visible and Infrared Survey Telescope for Astronomy (VISTA), the largest survey telescope in operation.

The extremely arid conditions and high altitude of the Paranal region make it an optimum site to locate an astronomical observatory. The otherworldliness and remoteness of the area add to the adventure of conducting cutting-edge astronomy.

26 April 2010

Starbursting Sculptor Galaxy

NGC 253, also known as the Sculptor Galaxy, is the brightest of the Sculptor Group of galaxies, found in the constellation of the same name, and lying approximately 13 million light-years from Earth. The Sculptor Galaxy is known as a starburst galaxy for its current high rate of star formation, one result of which is its superwind, a stream energetic material spewing out from the centre of the galaxy out into space. The purple light comes from that frenzy of star formation, which originally began 30 million years ago, while the yellowish colour is created by dust lit up by young, massive stars.

This image combines observations performed through three different filters (B, V, R) with the 1.5-metre Danish telescope at the ESO La Silla Observatory in Chile.

19 April 2010

The Glow of the Lagoon Nebula

Gas and dust condense, beginning the process of creating new stars in this image of Messier 8, also known as the Lagoon Nebula. Located four to five thousand light-years away, in the constellation of Sagittarius (the Archer), the nebula is a giant interstellar cloud, one hundred light-years across. It boasts many large, hot stars, whose ultraviolet radiation sculpts the gas and dust into unusual shapes. Two of these giant stars illuminate the brightest part of the nebula, known as the Hourglass Nebula, a spiralling, funnel-like shape near its centre. Messier 8 is one of the few star-forming nebulae visible to the unaided eye, and was discovered as long ago as 1747, although the full range of colours wasn’t visible until the advent of more powerful telescopes. The Lagoon Nebula derives its name from the wide lagoon-shaped dark lane located in the middle of the nebula that divides it into two glowing sections.

This image combines observations performed through three different filters (B, V, R) with the 1.5-metre Danish telescope at the ESO La Silla Observatory in Chile.

12 April 2010

Stellar Titans of Pismis 24

Home to some of the largest stars ever discovered, the open stellar cluster Pismis 24 blazes from the core of NGC 6357, a nebula in the constellation of Scorpius (the Scorpion). Several stars in the clusters weigh in at over 100 times the mass of the Sun, making them real monster stars. The strange shapes taken by the clouds are a result of the huge amount of blazing radiation emitted by these massive, hot stars. The gas and dust of the nebula hide huge baby stars in the nebula from telescopes observing in visible light, as well as adding to the hazy appearance of the image.

This image combines observations performed through three different filters in visible light (B, V, R) with the 1.5-metre Danish telescope at the ESO La Silla Observatory in Chile.

5 April 2010

Moonlit panorama at La Silla

This panoramic image shows the La Silla observatory glistening under the cool glow of moonlight. Because the image wraps around almost a full 360 degrees, the angle of the lighting becomes downright surreal ; notice how the photographer’s shadow seems to stretch towards the Moon, and how the shiny ESO 3.6-metre telescope in the foreground appears to reflect light from a source located opposite the Moon. Fortunately, such optical trickery does not trouble La Silla’s fleet of telescopes, which reside at an altitude of 2,400 metres in the arid Chilean Atacama Desert. In fact, La Silla’s MPG/ESO 2.2-metre telescope has snapped some of astronomy’s iconic images with the Wide Field Imager (WFI) camera. Also at this observatory, the 3.58-metre New Technology Telescope (NTT) broke new ground for telescope engineering and design and was the first in the world to have a computer-controlled main mirror (active optics), a technology developed at ESO and now applied to most of the world's current large telescopes. A spectrograph called HARPS (High Accuracy Radial velocity Planet Searcher), mounted on the ESO 3.6-metre telescope, stands as the world’s foremost exoplanet hunter. La Silla, ESO’s first observatory, remains at the cutting-edge of astronomical discovery.

A virtual tour is available here

29 March 2010

Assembly of a European ALMA Antenna

A European antenna for ALMA, the Atacama Large Millimeter/submillimeter Array, is placed on its base. The 12-metre diameter reflecting dish is attached to the base, with the whole structure weighing over 100 tonnes. When complete, the reflecting surface of the dish will be accurate to less than the thickness of a sheet of paper, and the antenna will be able to point precisely enough to pick out a golf ball at a distance of 15 kilometres. This is the second European antenna to be assembled at the 2,900-metre altitude Operations Support Facility in Chile. The antennas will ultimately be transported to the Chajnantor plateau, 5000 metres above sea level in the Chilean Andes.

ALMA, which will comprise 66 giant 12-metre and 7-metre diameter antennas observing the Universe at millimetre and submillimetre wavelengths, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ESO has contracted with the AEM (Alcatel Alenia Space France, Alcatel Alenia Space Italy, European Industrial Engineering S.r.L., MT Aerospace) Consortium for the supply of 25 of the 12-metre diameter ALMA antennas.

Showing 21 to 40 of 52
Bookmark and Share

Also see our