Imágenes de la semana

14 de Agosto de 2008: 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. This image was obtained in mid-2002 with the NACO instrument at the 8.2-m VLT Yepun telescope. It combines frames in three infrared wavebands between 1.6 and 3.5 µm. The compact objects ...

7 de Agosto de 2008: 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. Photo taken in November 2007.

30 de Julio de 2008: The "Very Large Telescope Video Collection 2008" features High Definition video material which was obtained in June 2008. 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. The material has been edited especially for broadcast use, without commentary or music.

17 de Julio de 2008: 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.

7 de Julio de 2008: Mientras ALMA se encuentra actualmente en construcción, los astrónomos ya están realizando observaciones en el área de la astronomía milimétrica y submilimétrica en Chajnantor, con el Atacama Pathfinder Experiment (APEX). Este es un telescopio de 12 metros de diámetro con tecnología de última generación. Opera en el sitio de ALMA y se basa en un prototipo de antena del mismo proyecto. Su óptica fue modificada y la superficie de la antena cuenta con una mayor precisión. Además, está diseñado para aprovechar la excelente nitidez del cielo, realizando observaciones en longitudes de onda entre los 0,2 y 1,4 mm. Esta imagen está disponible en la tienda virtual ESOshop

1 de Julio de 2008: 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 in the near-ultraviolet 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.

23 de Junio de 2008: El serpenteante camino que une el Campamento de Apoyo a la Operaciones de ALMA, ubicado a 3000 metros de altura en los Andes chilenos, con el Lugar de Operaciones de las Antenas, a 5000 metros de altura, cruza un área dominada por enormes cactus (Echinopsis Atacamensis). Estos cactus crecen un promedio de 1 cm al año y llegan a alcanzar alturas de hasta 9 mts. El Embajador Fotográfico de ESO Stéphane Guisard inmortalizó el hermoso cielo que cubre esta zona ubicada en el Desierto de Atacama en Chile. Esta imagen es parte de la prestigiosa exhibición fotográfica internacional El Mundo de Noche – Un mundo, Un Cielo. El Observatorio Europeo Austral (ESO) produjo una versión para Chile de esta exhibición sin fines de lucro, en el marco del Año Internacional de la Astronomía 2009.

10 de Junio de 2008: 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. The summit of Paranal has been blasted away so to create the flat platform that supports the 4 Unit Telescopes, as well as the network of tunnels that transport the light from the telescopes to the interferometric laboratory. On this 1994 ...

26 de Mayo de 2008: El cielo rotante sobre el VLT (Very Large Telescope) de ESO, en Paranal. Esta larga exposición muestra a las estrellas rotando alrededor del polo sur (izquierda) y el polo norte (derecha) celestes, situándose el ecuador celeste en el centro de la imagen -donde parece que las estrellas se mueven en línea recta-. También es visible el movimiento de la cúpula del VLT.

13 de Mayo de 2008: Heavyweights at 4,000 metre 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 2,900 metre altitude and the AOS at 5,000 metres. The first transporter ("Otto") is travelling unloaded, while the second one ("Lore") is carrying the 115-tonne antenna dummy.

4 de Mayo de 2008: 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 ...

20 de Marzo de 2008: The 8.2-m primary mirror of Yepun, Unit Telescope 4 of ESO's Very Large Telescope, after its recoating in early March

11 de Marzo de 2008: The central region of the Orion Nebula (M42, NGC 1976) as seen in the near-infrared by the High Acuity Wide field K-band Imager (HAWK-I) instrument at ESO's Very Large Telescope at Paranal.

25 de Febrero de 2008: Arrival of the ALMA Antenna Transporters at the Operations Support Facility (OSF) in Chile as the convoy passed through the Valle de Luna.

11 de Febrero de 2008: La determinación de la distancia a RS Pup, siguiendo el método del astrónomo norteamericano Robert Havlen, se basa en la medición de la diferencia de fase entre la variación de la estrella y la variación de características nebulares aisladas. Debido a que la luminosidad de la estrella cambia en un patrón muy distintivo, la presencia de la nebulosa permite a los astrónomos ver ecos de luz y utilizarlos para medir la distancia a la estrella. La luz que viajó desde la estrella a un grano de polvo y luego al telescopio llega un poco más tarde que la luz que llega directamente de la estrella al telescopio. En consecuencia, si medimos el brillo de una mancha o zona de polvo aislada y específica en la nebulosa, obtendremos una curva de brillo que tiene la misma forma que la variación de la Cefeida, pero desplazada en el tiempo. Este retraso se ...

29 de Enero de 2008: Artist's impression of the disc of matter surrounding the young stellar object MWC 147 as inferred from observations made with ESO's Very Large Telescope Interferometer. Thanks to these observations, astronomers have probed the inner parts of the disc of material surrounding the MWC 147, witnessing how it gains its mass before becoming an adult. A slice has been cut to show the inner structure better. The disc extends out to 100 times the distance between the Earth and the Sun (100 Astronomical Units — 100 AU). It is inclined by about 50 degrees as seen from Earth. The dust in the outer disc emits mainly at mid-infrared wavelengths, while close to the star there is also strong near-infrared emission from very hot gas. This gas is transported towards the forming star, increasing its mass at a rate of 7 millionths of the mass of the Sun — or about 2 ...

21 de Enero de 2008: 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'). This triplet of galaxies makes up part of the Hickson Compact Group HCG 90. 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 size of the image is about 5.3 arcminutes. The image is based on data obtained with the VLT FORS1 instrument on ESO's Very Large Telescope through three different filters, B, V, and R. The data were extracted from the ESO Science ...

14 de Enero de 2008: Este cuarteto es uno de los más bellos ejemplos de un grupo compacto de galaxias. Además es un excelente laboratorio para estudiar las interacciones entre galaxias y los efectos en la formación de estrellas.

7 de Enero de 2008: Estas extrañas formaciones de nieve y el hielo, llamadas "penitentes", se dan en regiones de gran altitud, como el llano de Chajnantor, cerca de donde se ubicará el conjunto ALMA. Se trata de láminas de hielo producidas por el contraste entre la sublimación y la fusión de la nieve. En Chajnantor, durante el solsticio de verano, el Sol está cerca del cenit al mediodía, y los penitentes adquieren formas verticales. Esta imagen fue tomada en diciembre de 2005. Esta imagen está disponible como imagen enmarcada en la tienda ESOshop.

24 de Diciembre de 2007: Una exposición de 30 minutos en banda K del VLT/NACO fue combinada con imágenes de archivo en banda B e I del HST/ACS para producir una imagen en tres colores del sistema de galaxias interactuante denominado "el Pájaro". La imagen de NACO ha permitido a los astrónomos no solamente examinar las dos galaxias ya conocidas, sino identificar un tercer componente claramente separado, una enorme galaxia irregular que parece formar estrellas a un ritmo frenético. La imagen final en color fue producida por Henri Boffin (ESO).