Comunicados de Prensa

18 de Mayo de 2001: New, trailblazing observations with the ESO Very Large Telescope (VLT) at Paranal lend strong support to current computer models of the early universe: It is "spongy", with galaxies forming along filaments, like droplets along the strands of a spiders web. A group of astronomers at ESO and in Denmark [1] determined the distances to some very faint galaxies in the neighbourhood of a distant quasar. Plotting their positions in a three-dimensional map, they found that these objects are located within a narrow "filament", exactly as predicted by the present theories for the development of the first structures in the young universe. The objects are most likely "building blocks" from which galaxies and clusters of galaxies assemble.

18 de Mayo de 2001: New images from the VLT show that one of the two nuclei of Comet LINEAR (C/2001 A2), now about 100 million km from the Earth, has just split into at least two pieces. The three fragments are now moving through space in nearly parallel orbits while they slowly drift apart. This comet will pass through its perihelion (nearest point to the Sun) on May 25, 2001, at a distance of about 116 million kilometres. It has brightened considerably due to the splitting of its "dirty snowball" nucleus and can now be seen with the unaided eye by observers in the southern hemisphere as a faint object in the southern constellation of Lepus (The Hare).

9 de Mayo de 2001: Did the star HD 82943 swallow one of its planets? What may at a first glance look like the recipe for a dramatic science-fiction story is in fact the well-considered conclusion of a serious scientific study, to be published by a group of astronomers in Switzerland and Spain [1] in tomorrow's issue of the international research journal "Nature".

25 de Abril de 2001: Using the FORS1 multi-mode instrument at the 8.2-metre VLT ANTU telescope on Paranal during a microlensing event, the team was able to obtain detailed spectra of the different parts of the remote star. In doing so, they managed to probe its gaseous atmosphere at different depths. This is the first time that it has been possible to obtain detailed, spatially resolved spectra across the full face of a normal star other than the Sun [4].

10 de Abril de 2001: The Osservatorio Astronomico Capodimonte Deep Field (OACDF) is a multi-colour imaging survey project that is opening a new window towards the distant universe. It is conducted with the ESO Wide Field Imager (WFI) , a 67-million pixel advanced camera attached to the MPG/ESO 2.2-metre telescope at the La Silla Observatory (Chile). As a pilot project at the Osservatorio Astronomico di Capodimonte (OAC) [1], the OACDF aims at providing a large photometric database for deep extragalactic studies, with important by-products for galactic and planetary research. Moreover, it also serves to gather experience in the proper and efficient handling of very large data sets, preparing for the arrival of the VLT Survey Telescope (VST) with the 1 x 1 degree 2 OmegaCam facility.

6 de Abril de 2001: Representatives from Europe, Japan, and North America met in Tokyo today and signed a Resolution affirming their mutual intent to construct and operate a giant radio telescope in co-operation with the Republic of Chile, where the telescope will be located.

4 de Abril de 2001: The intensive and exciting hunt for planets around other stars ("exoplanets") is continuing with great success in both hemispheres. Today, an international team of astronomers from the Geneva Observatory and other research institutes [1] is announcing the discovery of no less than eleven new, planetary companions to solar-type stars, HD 8574, HD 28185, HD 50554, HD 74156, HD 80606, HD 82943, HD 106252, HD 141937, HD 178911B, HD 141937, among which two new multi-planet systems. The masses of these new objects range from slightly less than to about 10 times the mass of the planet Jupiter [2]. The new detections are based on measured velocity changes of the stars [3], performed with the CORALIE spectrometer on the Swiss 1.2-metre Leonard Euler telescope at the ESO La Silla Observatory, as well as with instruments on telescopes at the Haute-Provence Observatory and on the Keck telescopes on Mauna Kea (Hawaii, USA).

30 de Marzo de 2001: A new astronomical instrument, TIMMI2, has just been installed on the ESO 3.6-metre telescope at La Silla. The first images have just been obtained and hold great promise for future research programmes with this facility. The Thermal Infrared MultiMode Instrument was built in a collaboration between ESO and a consortium headed by the Jena University Observatory (Germany). It detects infrared radiation in the 5-24 µm mid-IR spectral region. It is particularly well suited for observations of the complex processes that take place in the innermost regions of star-forming clouds. It is also a forerunner of a similar, but even more powerful instrument to be installed at the 8.2-metre VLT telescopes on Paranal during the next years. Among the first images are some of the most penetrating, mid-infrared views ever obtained of the central region of the Orion Nebula.

23 de Marzo de 2001: For hundreds of years, probably even longer, astronomers have sought the solitude, far from the disturbing influence of other human activities. Not without reason, their remote observatories have sometimes been likened with monasteries, sacred sites where man is closer to the skies and himself.

18 de Marzo de 2001: Following the "First Light" for the fourth of the 8.2-metre telescopes of the VLT Observatory on Paranal in September 2000, ESO scientists and engineers have just successfully accomplished the next major step of this large project.

13 de Marzo de 2001: Important scientific advances often happen when complementary investigational techniques are brought together. In the present case, X-ray and optical/infrared observations with some of the world's foremost telescopes have provided the crucial information needed to solve a 40-year old cosmological riddle.

8 de Marzo de 2001: The nearby galaxy Centaurus A harbours a supermassive black hole at its centre. Using the ISAAC instrument at the ESO Very Large Telescope (VLT), an international team of astronomers [1] has peered right through the spectacular dust lane of the peculiar galaxy Centaurus A, located approximately 11 million light-years away. They were able to probe the thin disk of gas that surrounds the very center of this galaxy. The new measurements show that the compact nucleus in the middle weighs more than 200 million solar masses! This is too much just to be due to normal stars. The astronomers thus conclude the existence of a supermassive black hole lurking at the centre of Centaurus A.

6 de Marzo de 2001: ESO has released a new image of the famous comet Hale-Bopp, where the large nucleus of ice and dust is still seen glowing. This is very unusual since the comet is currently in a very cold place, between the orbits of Saturn and Uranus, almost 2000 million kilometres away from the Sun.

2 de Marzo de 2001: Globular clusters are very massive assemblies of stars. More than 100 are known in the Milky Way galaxy and most of them harbour several million stars. They are very dense - at their centers, the typical distance between individual stars is comparable to the size of the Solar System, or 100 to 1000 times closer than the corresponding distances between stars in the solar neighborhood. Globular clusters are among the oldest objects known , with estimated ages of 11 to 15 billion years [1]. All stars in a globular cluster were formed at nearly the same moment, and from the same parent cloud of gas and dust. The original chemical composition of all stars is therefore the same. But now, an international group of astronomers [2], working with the UVES Spectrograph at the ESO Very Large Telescope (VLT), have obtained some unexpected results during a detailed analysis of dwarf stars in some globular clusters . Such stars have about the same mass as our Sun and like it, they evolve very slowly. Thus they still ought to have about the same abundances of most chemical elements.

7 de Febrero de 2001: Most astronomers would agree that the age of the Universe - the time elapsed since the "Big Bang" - is one of the "holy grails of cosmology". Despite great efforts during recent years, the various estimates of this basic number have resulted in rather diverse values. When derived from current cosmological models, it depends on a number of theoretical assumptions that are not very well constrained by the incomplete available observational data. At present, a value in the range of 10-16 billion years [1] is considered most likely. But now, an international team of astronomers [2] has used the powerful ESO Very Large Telescope (VLT) and its very efficient spectrograph UVES to perform a unique measurement that paves the way for a new and more accurate determination of the age of the Universe. They measured for the first time the amount of the radioactive isotope Uranium-238 in a star that was born when the Milky Way, the galaxy in which we live, was still forming. It is the first measurement ever of uranium outside the Solar System.

26 de Enero de 2001: Last year saw very good progress at ESO's Paranal Observatory, the site of the Very Large Telescope (VLT). The third and fourth 8.2-metre Unit Telescopes, MELIPAL and YEPUN had "First Light," while the first two, ANTU and KUEYEN, were busy collecting first-class data for hundreds of astronomers. Meanwhile, work continued towards the next phase of the VLT project, the combination of the telescopes into the VLT Interferometer. The test instrument, VINCI is now being installed in the VLTI Laboratory at the centre of the observing platform on the top of Paranal.

17 de Enero de 2001: Orion the Hunter is perhaps the best known constellation in the sky, well placed in the evening at this time of the year for observers in both the northern and southern hemispheres, and instantly recognisable. And for astronomers, Orion is surely one of the most important constellations, as it contains one of the nearest and most active stellar nurseries in the Milky Way, the galaxy in which we live.

11 de Enero de 2001: This Video Clip is issued on the web in conjunction with the release of an 18-min documentary video from the Science Festival of the "Physics On Stage" programme. This unique event took place during November 6-11, 2000, on the CERN premises at the French-Swiss border near Geneva, and formed part of the European Science and Technology Week 2000, an initiative by the European Commission to raise the public awareness of science in Europe.

10 de Enero de 2001: How do stars like our Sun come into being? Which fundamental processes are responsible for transforming a dark and diffuse interstellar cloud of gas and dust into a much denser, shining object? Astronomers have just taken an important step towards answering this fundamental question. Based on the most detailed study ever made of the internal structure of a small interstellar cloud, three scientists from ESO and the USA [1] have found that it is apparently on the verge of becoming unstable - and thus in the stage immediately preceding a dramatic collapse into a dense and hot, low-mass star.

4 de Enero de 2001: At the beginning of the new millennium, ESO and its staff are facing the future with confidence. The four 8.2-metre Unit Telescopes of the Very Large Telescope (VLT) are in great shape and the VLT Interferometer (VLTI) will soon have "first fringes". The intercontinental ALMA project is progressing well and concepts for extremely large optical/infrared telescopes are being studied.