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2 October 2006: Astronomers have found possible proofs of stellar vampirism in the globular cluster 47 Tucanae. Using ESO's Very Large Telescope, they found that some hot, bright, and apparently young stars in the cluster present less carbon and oxygen than the majority of their sisters. This indicates that these few stars likely formed by taking their material from another star.

15 March 2006: Studying several tens of distant galaxies, an international team of astronomers found that galaxies had the same amount of dark matter relative to stars 6 billion years ago as they have now. If confirmed, this suggests a much closer interplay between dark and normal matter than previously believed. The scientists also found that as many as 4 out of 10 galaxies are out of balance. These results shed a new light on how galaxies form and evolve since the Universe was only half its current age.

15 March 2005: On the basis of stellar spectra totalling more than 200 hours of effective exposure time with the 8.2-m VLT Kueyen telescope at Paranal (Chile), a team of astronomers [1] has made a surprising discovery about the stars in the giant southern globular cluster Omega Centauri. It has been known for some time that, contrary to other clusters of this type, this stellar cluster harbours two different populations of stars that still burn hydrogen in their centres. One population, accounting for one quarter of its stars, is bluer than the other. Using the FLAMES multi-object spectrograph that is particularly well suited to this kind of work, the astronomers found that the bluer stars contain more heavy elements than those of the redder population. This was exactly opposite to the expectation and they are led to the conclusion that the bluer stars have an overabundance of the light element helium of more than 50%. They are in fact the most helium rich stars ever found. But why is this so? The team suggests that this puzzle may be explained in the following way. First, a great burst of star formation took place during which all the stars of the red population were produced. As other normal stars, these stars transformed their hydrogen into helium by nuclear burning. Some of them, with masses of 10-12 times the mass of the Sun, soon thereafter exploded as supernovae, thereby enriching the interstellar medium in the globular cluster with helium. Next, the blue population stars formed from this helium-rich medium. This unexpected discovery provides important new insights into the way stars may form in larger stellar systems.

3 March 2005: An international team of astronomers have accurately determined the radius and mass of the smallest core-burning star known until now. The observations were performed in March 2004 with the FLAMES multi-fibre spectrograph on the 8.2-m VLT Kueyen telescope at the ESO Paranal Observatory (Chile). They are part of a large programme aimed at measuring accurate radial velocities for sixty stars for which a temporary brightness "dip" has been detected during the OGLE survey. The astronomers find that the dip seen in the light curve of the star known as OGLE-TR-122 is caused by a very small stellar companion, eclipsing this solar-like star once every 7.3 days. This companion is 96 times heavier than planet Jupiter but only 16% larger. It is the first time that direct observations demonstrate that stars less massive than 1/10th of the solar mass are of nearly the same size as giant planets. This fact will obviously have to be taken into account during the current search for transiting exoplanets. In addition, the observations with the Very Large Telescope have led to the discovery of seven new eclipsing binaries, that harbour stars with masses below one-third the mass of the Sun, a real bonanza for the astronomers.

22 October 2004: An international team of astronomers [2] has succeeded in measuring with high precision the velocities of a large number of planetary nebulae [3] in the intergalactic space within the Virgo Cluster of galaxies. For this they used the highly efficient FLAMES spectrograph [4] on the ESO Very Large Telescope at the Paranal Observatory (Chile). These planetary nebulae stars free floating in the otherwise seemingly empty space between the galaxies of large clusters can be used as "probes" of the gravitational forces acting within these clusters. They trace the masses, visible as well as invisible, within these regions. This, in turn, allows astronomers to study the formation history of these large bound structures in the universe. The accurate velocity measurements of 40 of these stars confirm the view that Virgo is a highly non-uniform galaxy cluster, consisting of several subunits that have not yet had time to come to equilibrium. These new data clearly show that the Virgo Cluster of galaxies is still in its making. They also prove for the first time that one of the bright galaxies in the region scrutinized, Messier 87, has a very extended halo of stars, reaching out to at least 65 kpc. This is more than twice the size of our own galaxy, the Milky Way.

7 May 2004: A European team of astronomers [1] are announcing the discovery and study of two new extra-solar planets (exoplanets). They belong to the OGLE transit candidate objects and could be characterized in detail. This trebles the number of exoplanets discovered by the transit method; three such objects are now known. The observations were performed in March 2004 with the FLAMES multi-fiber spectrograph on the 8.2-m VLT Kueyen telescope at the ESO Paranal Observatory (Chile). They enabled the astronomers to measure accurate radial velocities for forty-one stars for which a temporary brightness "dip" had been detected by the OGLE survey. This effect might be the signature of the transit in front of the star of an orbiting planet, but may also be caused by a small stellar companion. For two of the stars (OGLE-TR-113 and OGLE-TR-132), the measured velocity changes revealed the presence of planetary-mass companions in extremely short-period orbits. This result confirms the existence of a new class of giant planets, designated "very hot Jupiters" because of their size and very high surface temperature. They are extremely close to their host stars, orbiting them in less than 2 (Earth) days. The transit method for detecting exoplanets will be "demonstrated" for a wide public on June 8, 2004, when planet Venus passes in front of the solar disc, cf. the VT-2004 programme.

8 July 2002: The first observations of stellar spectra have just been performed with the new GIRAFFE multi-object spectrograph on the ESO Very Large Telescope (VLT) at the Paranal Observatory in Chile. This milestone event was achieved in the early morning of July 3, 2002. It signifies another important step towards the full implementation of the extremely powerful Fibre Large Array Multi-Element Spectrograph (FLAMES), one of the main instruments for the ESO VLT. This project is co-ordinated by ESO and incorporates many complex components that have been constructed at various research institutions in Europe and Australia. The GIRAFFE spectrograph provides unique possibilities for detailed observations of the properties of individual stars located in our Milky Way galaxy ( PR 16b/02 ) as well as in other galaxies of the Local Group.

28 January 2002: The ESO Very Large Telescope (VLT) at the Paranal Observatory is being equipped with many state-of-the-art astronomical instruments that will allow observations in a large number of different modes and wavebands [1]. Soon to come is the Fibre Large Array Multi-Element Spectrograph (FLAMES) , a project co-ordinated by ESO. It incorporates several complex components, now being constructed at various research institutions in Europe and Australia.

One of these, a true technological feat, is a unique system of 15 deployable fibre bundles, the so-called Integral Field Units (IFUs) . They can be accurately positioned within a sky field-of-view measuring no less that 25 arcmin in diameter, i.e., almost as large as the full Moon . Each of the IFUs looks like an insect's eye and images a small sky area (3 x 2 arcsec 2 ) with a multiple microlens. From each IFU, 20 narrow light beams are sent via optical fibres to an advanced spectrograph. All 300 spectra are recorded simultaneously by a sensitive digital camera.

A major advantage of this technique is that, contrary usual spectroscopic observations in which spectral information is obtained along a (one-dimensional) line on the sky, it now allows (two-dimensional) area spectroscopy . This will permit extremely efficient spectral observations of many celestial objects, including faint galaxies, providing detailed information about their internal structure and motions. Such studies will have an important impact on our understanding, e.g., of the early evolution of galaxies , the main building blocks in the Universe.

The IFUs have been developed by a team of astronomers and engineers [2] at the Observatoire de Paris-Meudon. All IFU components are now at the ESO Headquarters in Garching (Germany) where they are being checked and integrated into the instrument [3].

19 June 1998: The Anglo-Australian Observatory (AAO) at Epping (New South Wales, Australia) has been awarded the contract to build a fibre positioner for the European Southern Observatory's Very Large Telescope (VLT). This new, large astronomical facility is located at the Paranal Observatory in Chile and will feature four Unit Telescopes, each with a main mirror of 8.2-m diameter.