Comunicati stampa

09 Febbraio 1996: In the context of a comprehensive Key-Programme , carried out with telescopes at the ESO La Silla Observatory, a team of European astronomers [1]. has recently obtained radial velocities for more than 5600 galaxies in about 100 rich clusters of galaxies. With this programme the amount of information about the motions of galaxies (the kinematical data) in such clusters has almost been doubled. This has allowed the team to study the distribution of the cluster masses, and also the dynamical state of clusters in new and interesting ways.

09 Febbraio 1996: One more cosmic mirage has been found with the ESO 3.5-metre New Technology Telescope (NTT). It consists of two images of the same quasar, seen very close to each other in the southern constellation of Hydra (The Water-Snake).

02 Febbraio 1996: This photo was obtained on 15 January 1996 and shows the progression of the work on the enclosure for VLT Unit Telescope no. 1 on Cerro Paranal.

02 Febbraio 1996: This aerial photo was obtained on 16 January 1996 and shows the progression of the work at the VLT Observatory on Cerro Paranal in the Chilean Atacama desert, about 130 km south of the town of Antofagasta.

19 Gennaio 1996: How many moons has Saturn, the second-largest planet in the solar system? Until recently, the best answer was eighteen, ranging from innermost Pan that circles the planet 75,000 km above the cloud tops in a little less than 14 hours, to distant Phoebe, 13 million km away in a reverse ('retrograde') 550-day orbit [1]. Now the situation is less clear.

12 Gennaio 1996: For some time, the astronomical community in Australia has expressed interest in closer ties to ESO. One of the main reasons is the construction of the ESO Very Large Telescope (VLT), of which the first 8.2 m unit telescope is scheduled for completion less than 2 years from now.

05 Gennaio 1996: A few months ago, Periodic Comet Schwassmann-Wachmann 3 underwent a dramatic and completely unexpected, thousand-fold brightening. At that time, the cause for this interesting event was unknown. However, observations with the two largest ESO telescopes have now shown that the "dirty snowball" nucleus of this comet has recently split into at least four individual pieces. There is little doubt that the outburst and the splitting event(s) are closely related and that the greatly increased dust and gas production is due to "fresh" material of the icy cometary nucleus becoming exposed to the surrounding space for the first time.

05 Dicembre 1995: As the ESO Very Large Telescope (VLT) rapidly takes on shape, Europe has just come one step closer to the realisation of its 556 million DEM astronomical showcase project.

20 Novembre 1995: Today, forty 16-18 year old students and their teachers are concluding a one-week, educational `working visit' to the ESO Headquarters in Garching (See ESO Press Release 14/95 of 8 November 1995). They are the winners of the Europe-wide contest `Europe Towards the Stars', organised by ESO with the support of the European Union, under the auspices of the Third European Week for Scientific and Technological Culture.

20 Novembre 1995: New observations of the spectrum of the rapidly spinning neutron star (the `pulsar') in the Crab Nebula have been carried out with the ESO 3.5-metre New Technology Telescope (NTT) by a group of Italian astronomers [1]. Because of greatly improved spectral resolution which allows to register even very fine details in the pulsar's spectrum, they are able to determine for the first time with high accuracy the overall dependance of the emission on wavelength, i.e. the 'shape' of the spectrum. Quite unexpectedly, they also detect a hitherto unknown 100 A (10 nm) broad 'absorption dip', which can be securely attributed to the pulsar. These results open an exciting new window for the study of the extreme physical processes close to a pulsar.

13 Novembre 1995: This photo shows the state of construction of the enclosure (`dome') for VLT Unit Telescope No. 1 on Paranal in late October 1995. It will be ready in 1996, and will later serve to protect the first 8.2-metre VLT telescope, for which the 'first light' is foreseen in late 1997/early 1998.

13 Novembre 1995: In 1989, the European Southern Observatory (ESO), the European Organisation for Astronomy, awarded to REOSC, a subsidiary of the SFIM Group and located in Saint Pierre du Perray (France), a comprehensive contract for the polishing of four 8.2-metre diameter mirrors for the unit telescopes of the ESO Very Large Telescope (VLT) project. These mirrors are the largest ever manufactured and polished. This contract comprises not only the polishing and high-precision optical testing of each giant mirror, but also the safe condition of transportation of the blanks which were manufactured by Schott Glaswerke in Mainz (Germany). In order to fulfill the contract, REOSC conceived, built and equipped a novel, high-tech workshop which would allow to polish and test the mirrors, each of which has a surface area of more than 50 square metres.

08 Novembre 1995: Following the very successful events of 1993 and 1994 [1], ESO again opens its doors for an 'educational adventure' next week. It takes place within the framework of the 'Third European Week for Scientific and Technological Culture', initiated and supported by the European Commission. On Tuesday, November 14, 1995, about forty 16-18 year old students and their teachers will converge towards Munich from all corners of Europe. They are the happy winners of a Europe-wide astronomy contest (`Europe Towards the Stars') that took place during the summer and early autumn. Their prize is a free, week-long stay at the Headquarters of the European Southern Observatory. During this time they will work with professional astronomers and get a hands-on experience within modern astronomy and astrophysics at one of the world's foremost international centres.

23 Ottobre 1995: Astronomers from the University of Leiden have discovered an extremely distant, enormous gas cloud. It is probably a 'cocoon' from which one or more galaxies are in the process of being born, soon after the Big Bang. The observations also indicate that this gas cloud is slowly rotating, an entirely new result of great cosmological significance. The discovery was made with the ESO 3.5-metre New Technology Telescope (NTT) at La Silla in Chile by a team consisting of Rob van Ojik, Huub Röttgering, Chris Carilli, George Miley and Malcolm Bremer from Leiden Observatory (The Netherlands) and Duccio Macchetto of the European Space Agency (ESA) stationed in Baltimore, U.S.A. Their extensive observations are reported in an article accepted for publication in the professional European journal `Astronomy and Astrophysics' and also as a chapter of van Ojik's Ph.D. thesis which is defended at the University of Leiden on October 25. This exciting result casts new light on one of the most important questions of modern cosmology, i.e. how lumpy galaxies were 'born' out of the extremely smooth fireball produced during the Big Bang.

23 Ottobre 1995: Adaptive Optics (AO) is the new "wonder-weapon" in ground-based astronomy. By means of advanced electro-optical devices at their telescopes, astronomers are now able to ``neutralize'' the image-smearing turbulence of the terrestrial atmosphere (seen by the unaided eye as the twinkling of stars) so that much sharper images can be obtained than before. In practice, this is done with computer-controlled, flexible mirrors which refocus the blurred images up to 100 times per second, i.e. at a rate that is faster than the changes in the atmospheric turbulence.

15 Settembre 1995: Four European astronomers [1] have taken advantage of the superb imaging quality of the ESO 3.5-metre New Technology Telescope (NTT) at the La Silla observatory, to detect a galaxy at an extremely large distance. They conclude that its redshift [2] is z = 4.4; thus, this galaxy is by far the most remote ever detected. In fact, it has taken its light about 90 percent of the age of the Universe to reach us, and we now observe this early object as it appeared, only 1 - 2 billion years [3] after the Universe was created in the Big Bang. Still, the galaxy contains a considerable amount of elements that must have been produced in stars. This proves that stars were formed in normal galaxies, already before this very early epoch.

13 Settembre 1995: The construction of the ESO Very Large Telescope (VLT) advances rapidly, both in Europe and in Chile. These three photos show some of the main mechanical parts of the first 8.2-metre telescope, as they presented themselves in Milan (Italy) on Thursday, September 7, 1995. Two versions of these photos, one smaller and one larger and with better image resolution, are accessible for convenient transfer over the networks.

11 Settembre 1995: Comet Hale-Bopp is known to possess a bright coma, despite its large distance from the Sun, almost 1,000 million km. Observations have shown that this coma consists of dust particles of different sizes that have been ejected from the comet's nucleus.

05 Settembre 1995: A brand new image of comet Hale-Bopp, showing its famous jet that comes out of the nuclear region, has just been released.

01 Settembre 1995: A new image of comet Hale-Bopp, taken at ESO's observatory in La Silla, sheds new light on the structure of this peculiar comet.