Visual of the Week - Archive
30 September 2008: Milky Way above Paranal
A night of work for the Paranal Observatory, in the Chilean Atacama Desert. This picture, taken on 20 September, shows the incredible beauty of the night sky above the most advanced telescope in the world, ESO's Very Large Telescope. The Milky Way is clearly seen in this superb image.
Credit: Sebastian Deiries (ESO).
22 September 2008: Magnificent spiral galaxy, NGC 7424
Composite colour-coded image of a magnificent spiral galaxy, NGC 7424, at a distance of 40 million light-years. It is based on images obtained with the multi-mode VIMOS instrument on the ESO Very Large Telescope (VLT) in three different wavelength bands. The image covers 6.5 x 7.2 square arcminutes on the sky. North is up and East is to the right.
Read more about this superb object in ESO 33/04.
5 September 2008: Paranal and Conjunction
The Paranal platform on the evening of 1 September 2008. Shining above one of ESO's Very Large Telescope 8.2-m Unit Telescopes and two of the smaller 1.8-m Auxiliary Telescopes, are the Moon, Mars, Mercury and Venus.
Photo: Stephane Guisard. This image can only be used with the permission of the author.
21 August 2008: The Globular Cluster NGC 3201
Colour-composite image of the globular cluster NGC 3201, obtained with the WFI instrument on the ESO/MPG 2.2-m telescope at La Silla. Globular clusters are large aggregates of stars, that can contain up to millions of stars. They are among the oldest objects observed in the Universe and were presumably formed at about the same time as the Milky Way Galaxy, in the early phase after the Big Bang. This particular globular cluster is located about 16 000 light-years away towards the Southern Vela constellation. The data were obtained as part of the ESO Imaging Survey (EIS), a public survey being carried out by ESO and member states, in preparation for the VLT First Light.
An high-resolution, 2.6 MB version of this image is also available.
The original image and astronomical data can be retrieved from the EIS Pre-Flames Survey Data Release pages, where many other nice images are also available.
14 August 2008: The Centre of the Milky Way
The centre of our Milky Way galaxy is located in the southern constellation Sagittarius (The Archer) and is "only" 26,000 light-years away. On high-resolution images, it is possible to discern thousands of individual stars within the central, one light-year wide region.
Using the motions of these stars to probe the gravitational field, observations over the last decade have shown that a mass of about 3 million times that of the Sun is concentrated within a radius of only 10 light-days of the compact radio and X-ray source SgrA* ("Sagittarius A") at the centre of the star cluster.
This means that SgrA* is the most likely counterpart of the black hole believed to exist at the centre of our Galaxy.
Find more information on this image as well as other formats in the Gallery.
7 August 2008: Paranal in Atacama Desert
Paranal, the site of the VLT, was chosen for its unique characteristics: extreme dryness, very low cloud coverage, high altitude, and distant from any source of pollution. This wide-angle shot of the Atacama desert around Paranal, which shows the VLT and, in foreground, VISTA, summarizes it all. Find more formats of this image in the Gallery.
30 July 2008: VLT Video Collection
The "Very Large Telescope Video Collection 2008" features High Definition video material which was obtained in June 2008.The collected footage has been edited to the needs of broadcasters and can be downloaded from our broadcast pages. For the first time, ESO distributes HD-footage of the world's most advanced ground-based observing facility and provides free access to video sequences of outstanding technical quality and beauty.
17 July 2008: Carrying a 100-ton antenna
The first successful movement of an ALMA antenna took place at the Operations Support Facility (OSF) on 8 July 2008. The antenna transporter "Lore", one of the two units manufactured by Scheuerle under contract by ESO and delivered recently at the OSF, has been used to move one 12-m antenna from their site erection facility to an external antenna pad for sky testing. An high resolution version of this image is available. Photo: Pascal Martinez (ESO).
A movie showing this movement is available.
7 July 2008: APEX at Chajnantor
While ALMA is currently under construction, astronomers are already doing millimetre and submillimetre astronomy at Chajnantor, with the Atacama Pathfinder Experiment (APEX). This is a new-technology 12-m telescope, based on an ALMA prototype antenna, and operating at the ALMA site. It has modified optics and an improved antenna surface accuracy, and is designed to take advantage of the excellent sky transparency working with wavelengths in the 0.2 to 1.4 mm range. More...
1 July 2008: X-Shooter
The image shows X-shooter, the first of the second generation VLT instruments, under test in the integration lab at ESO, Garching. The instrument has been built by a Consortium including ESO and institutes from Denmark, Italy, The Netherlands and France, and will start operation at the telescope in 2009. X-shooter is a single target, wide band, intermediate spectral resolution spectrograph, designed to get the full spectrum of the faintest cosmic sources from the atmospheric cutoff to the infrared K-band in a single exposure. In this image the instrument is shown as mounted on a telescope Cassegrain focus simulator, pointing at a large zenith distance. At the centre is the cryostat with the near-infrared arm of the spectrograph and at the left is the lower side of the visual spectrograph with its CCD detector. The two large boxes on the sides host the control electronics of the instrument. More details on the instrument can be found at http://www.eso.org/sci/facilities/develop/instruments/xshooter/.
23 June 2008: Cacti and Milky Way
The winding road connecting the ALMA Operation Support Facility at 3000m altitude to the Array Operation Site (5000m high) passes an area between 3500m and 3800m dominated by large cacti (Echinopsis Atacamensis). These cacti grow on average 1cm per year, and reach heights of up to 9m. Stephane Guisard recently captured the beautiful sky above this unique location in the Chilean Atacama Desert. The Milky Way is seen in all its glory, as well as, in the lower right, the Large Magellanic Cloud.
Photo: Stephane Guisard. This image can only be used with the permission of the author.
16 June 2008: A microlensing event
When a planetary system passes close to the line of sight towards a distant background source star, the gravity of the planet and its host star can act like a lens to magnify the background star's light, causing a brief change in its apparent brightness. This phenomenon, known as gravitational microlensing, provides a powerful way to detect planets around stars and to learn about their properties.
Shown here is a 8.2"x 8.2" J-band NACO image of the microlensing event MOA-BLG-2007-192 (at centre of circle), which harbours a very low mass planet of about 3 Earth masses in a 0.6 AU orbit around either a low-mass star or a brown dwarf. Future follow up observations with NACO or HST will help to decide the nature of the planet host star.
Details can be found in an upcoming article of D. Bennett et al. to be published in the Astrophysical Journal, and in this press release:
http://www.nsf.gov/news/news_summ.jsp?cntn_id=111642
Image credit: D. Bennett, D. Kubas, S. Brillant, and collaborators
This is the
ESO Chile Image of the Month for June.
10 June 2008: Paranal in 1994
This aerial view of Cerro Paranal, the site of ESO's
Very Large Telescope, was obtained in
1994. It shows
the construction of the concrete base
for the four telescope enclosures.
To the left and a little lower than the rest
of the platform is the excavation for the control
building. The platform altitude is about 2640 metres
above sea level and it measures about 150 metres
across. The width of the access road is no less than
12 metres, i.e. nearly equal to that of a three-lane
highway; this is necessary to ensure the safe
transport of all telescope parts, especially the four
8.2-metre fragile mirrors, to the top.
For more information on the history of the VLT, please have a look at
UT1 First Light Event Photos:
First Set,
Second Set,
and
Third Set.
26 May 2008: Trailing stars above Paranal
The rotating sky above ESO's Very Large Telescope at Paranal. This long exposure shows the stars rotating around the southern (left) and northern (right) celestial poles, the celestial equator being in the middle of the photo - where the stars seem to move in a straight line. The motion of the VLT's enclosures are also visible. Photo: Stephane Guisard. This image can only be used with the permission of the author.
19 May 2008: Milky Way above La Silla
On this image taken at La Silla on 10 May 2008, the 3.6-m telescope and the attached dome of the CAT is seen, beautifully illuminated by the setting Moon. The 3.6-m telescope is host to the HARPS instrument, perhaps the most successful exoplanet hunter that exists. It has, among others, discovered the system of planets around Gliese 581, including the most Earth-like planet found till now, Gliese 581c. The Milky Way with its myriad of stars and, most likely, plethora of planets still to be discovered, is also beautifully depicted in this 30-second exposure photo. Photo: Serge Brunier. This image can only be used with the permission of the author.
13 May 2008: Transporters at Chajnantor
Heavyweights at 4000m altitude: this photo shows the two ALMA antenna transporters during the final phase of the acceptance testing in April on the road between the ALMA OSF at 2900m altitude and the AOS at 5000m. The first transporter ("Otto") is travelling unloaded, while the second one ("Lore") is carrying the 115-ton antenna dummy. Photo: Stefano Stanghellini (ESO).
4 May 2008: Uranus and satellites
An image of the planet Uranus (located 20 Astronomical units from Earth) obtained at the Very Large Telescope Observatory using the Adaptive Optics system NAOS and the near-infrared imager CONICA to capture high-contrast images of the giant planet and its system of satellites and rings during its 2008 equinox. Every 42 years, the ring (and satellites) plane of Uranus crosses the Sun, providing us with a unique opportunity to observe the rings while they present their edge to us. Ring plane crossing also allow us to observe the rings form their dark side (i.e. while the Sun is illuminating them from the opposite side), so one can search for faint satellites, faint rings, or faint ring structures, which could not be seen otherwise. Ring Plane Crossings are also an excellent opportunity to observe mutual events between satellites such as eclipse or occultation phenomena.
The image above corresponds to a one minute exposure (maximum permitted time to prevent trailing of the moving satellites) obtained at 2.2 micron with a K band filter. The bandpass of this filter matches the absorption bands of methane, which is present in the atmosphere of Uranus, and has the effect of making the bright planet (almost) completely disappear from our images. Thanks to this observing trick, we can observe the faint rings and small satellites of Uranus, which would become invisible otherwise, lost in the glare of the planet. The bright spots on each side of Uranus are Miranda (~470km diam.) and Ariel (~1100km diam.), respectively to the right and left of the image. Two much smaller satellites can be seen just above the ring plane, to the left of the planet, the closer to Uranus being Puck (~150km diam.) and the other Portia (~100km), near the ring tip in this image.
A movie of these observations is also
available. The movie shows an animation of this system of satellites over a two hour period. You can easily see the impact of fluctuating seeing conditions on the image quality. Under good seeing, both small satellites Puck and Portia becomes clearly visible when they move along their orbital path, while the images start to blur when the seeing conditions degrade.
Credit: C. Dumas, B. Sicardy, and J.-E. Arlot
This is one of the
ESO Chile Image of the Month.
27 April 2008: Distant Galaxy Cluster
A composite infrared image of the X-ray luminous galaxy cluster XMMU J2235.3-2557 at redshift 1.4, one of the most distant galaxy clusters known.
The composite is made of 4 HAWK-I pointings in both J and Ks and covers 13.5 arc minutes on a side. The cluster is right in the middle of the frame and is difficult to see, given the large field of view, so a blow-up centred on the cluster is shown in the inset. As can be seen by eye, the core of the cluster is dominated by red galaxies with very similar colours. The stars in these galaxies are already very old. On average they formed when the Universe was only one billion years old. As one moves away from the center of the cluster, cluster galaxies become slightly bluer, suggesting that galaxies in the outskirts are either younger or have recently experienced a small amount of star formation (commonly called "frosting"). As one moves even further out, the authors hope to find small groups of galaxies that will, one day, merge with the core.
In the standard flat, lambda-dominated cosmology, the universe is 4.6 billion years old at redshift 1.4 and 1.1 billion years old at redshift 5. The universe at redshift 0 (today) is 13.7 billion years old.
At a redshift of 1.4, 10 arc minutes on the sky corresponds to a linear distance of 5 Mpc (15,000,000,000,000,000,000 km).
Authors: Chris Lidman, Piero Rosati, Masyuki Tanaka and the HAWK-I science verification team.
This is one of the
ESO Chile Image of the Month.
18 April 2008: The ALMA OSF
A dramatic picture of the ALMA Operations Support Facility (OSF), located 2900m high in the Chilean Atacama Desert, close to the town of San Perdo de Atacama. Visible from left to right are the OSF Building, still in construction, the ALMA Antenna Transporter carrying a dummy antenna, and four antennas, that are being prepared. In the background, lenticular clouds are seen over the Lascar Volcano.
Credit: Jean-Michel Moresmau (ESO)
Weeks from 27 March to 18 April were dedicated to the
Catch a Star! competition and the
James Bond at Paranal web site.
20 March 2008: Recoating Yepun's mirror
The 8.2-m primary mirror of Yepun, Unit Telescope 4 of ESO's Very Large Telescope, after its recoating in early March. Credit: Gerhard Huedepohl.
11 March 2008: The Orion Nebula
The central region of the Orion Nebula (M42, NGC 1976) as seen in the near-infrared by the HAWK-I instrument on the VLT.
25 February 2008: ALMA Transporters Arrive in Chile
Arrival of the ALMA Antenna Transporters at the Operations Support Facility (OSF) in Chile as the convoy passed through the Valle de Luna.
11 February 2008: Light echoes whisper the distance to a star
Taking advantage of the presence of light echoes, a team of astronomers have used an ESO telescope to measure, at the 1% precision level, the distance of a Cepheid - a class of variable stars that constitutes one of the first steps in the cosmic distance ladder. Credit: ESO.
29 January 2008: The Growing-up of a Star
Using ESO's Very Large Telescope Interferometer, astronomers have probed the inner parts of the disc of material surrounding a young stellar object, witnessing how it gains its mass before becoming an adult. Credit: ESO.
21 January 2008: Cosmic Interactions
Colour-composite image of the triplet of galaxies, catalogued as NGC 7173 (top), 7174 (bottom right) and 7176 (bottom left), and located 106 million light-years away towards the constellation of Piscis Austrinus (the 'Southern Fish'). The image is based on data obtained with the FORS1 instrument on ESO's Very Large Telescope through three different filters, B, V, and R. NGC 7173 and 7176 are elliptical galaxies, while NGC 7174 is a spiral galaxy with quite disturbed dust lanes and a long, twisted tail. This seems to indicate that the two lower galaxies - whose combined shape bears some resemblance to that of a sleeping baby - are currently interacting. Astronomers have suggested that the three galaxies will finally merge. The data were extracted from the ESO Science Archive and fully processed by Henri Boffin (ESO).
14 January 2008: Robert's Quartet
Robert's Quartet is a family of four very different galaxies, located at a distance of about 160 million light-years, close to the centre of the southern constellation of the Phoenix. Its members are NGC 87, NGC 88, NGC 89 and NGC 92, discovered by John Herschel in the 1830s. Credit: ESO.
7 January 2008: The White Penitents
Field of 'white penitents' at 5000m altitude on the Chajnantor plain, close to where the ALMA array will be located. These are ice blades produced by the competition between sublimation and melting of the snow. At Chajnantor at the summer solstice, the Sun is close to the zenith at noon, and penitents are vertical.
This is one of the images of the beautiful ESO Calendar 2008. Credit: ESO.
24 December 2007: The Tinker Bell Triplet
Using ESO's Very Large Telescope, an international team of astronomers has discovered a stunning rare case of a triple merger of galaxies. This system, which astronomers have dubbed 'The Bird' - albeit it also bears resemblance with a cosmic Tinker Bell - is composed of two massive spiral galaxies and a third irregular galaxy.
More...
17 December 2007: ALMA Transporters
On 3 and 4 December 2007, the two ALMA antenna transporters, Otto and Lore, were being loaded onto a barge on the Neckar at Heilbronn harbour (Germany) to start their long journey to Chile. From there, they will travel to Antwerpen (Belgium) and then put onto a ship towards the port of Mejillones, in the north of Chile, to finally reach the ALMA base, close to San Pedro de Atacama. Credit: ESO.
More...
10 December 2007: Antennas at Sunset
The first three Japanese ALMA antennas of the Atacama Compact Array (ACA) at the ALMA Operation Support Facility, located close to the town of San Pedro de Atacama in the Chilean Atacama Desert, at an altitude of 2900m. At the time of the picture, in November 2007, the antennas were undergoing final tests before being handed over to the ALMA Observatory. The 12-m antennas were built by MELCO for the National Astronomical Observatory of Japan, one of the partners in the ALMA partnership. Credit: H. Boffin/ESO/ALMA
More...
1 December 2007: Minister Marie-Dominique Simonet at Paranal
On 17 and 18 November 2007, the Regional Minister for Research of the Belgian French-speaking Community, Marie-Dominique Simonet, visited Paranal. This was part of a week-long visit to Brazil and Chile, in which the Minister promoted the 'Competitivity Poles' as well as Research and Education in this part of the world. Credit: ESO
More...
23 November 2007: Sunset over Paranal
Twice per year, the sunset passes exactly behind Paranal for somebody located on the summit of Armazones mountain, 20km away. Credit: Use of this image is only permitted with express permission from the author, Stephane Guisard. More...