Comunicados de Prensa

19 de Agosto de 1995: The newly discovered, bright Comet 1995 Q1 was again observed at La Silla last night (18 - 19 August 1995).

18 de Agosto de 1995: In the evening of August 17, 1995, famous comet hunter William Bradfield (Australia) discovered his seventeenth comet. He found the comet as a 6th magnitude object with a tail longer than 1 degree in the southern constellation Crater.

17 de Agosto de 1995: A few months ago, a violent stellar explosion – a supernova – was discovered in an extremely distant galaxy by an international team of astronomers [1]. This is the very promising first result of a recently initiated, dedicated search for such objects. Subsequent spectral observations have shown this to be the most distant supernova ever observed. Although it is very faint, it has been possible to classify it as a supernova of Type Ia, a kind that is particularly well suited for cosmological distance determinations.

2 de Agosto de 1995: The Antofagasta Earthquake of last Sunday, July 30, 1:15 hours, violently shook Cerro Paranal, the site where ESO, the European Southern Observatory, is building the VLT, the world's largest optical telescope. The quake's intensity in Paranal was estimated at grade 8 on the Richter scale.

19 de Junio de 1995: Based on exciting new data obtained with the ROSAT X-ray satellite and a ground-based telescope at the ESO La Silla Observatory, a team of European astronomers [2] has just discovered a very distant cluster of galaxies with unique properties. It emits the strongest X-ray emission of any cluster ever observed by ROSAT and is accompanied by two extraordinarily luminous arcs that represent the gravitationally deflected images of even more distant objects. The combination of these unusual characteristics makes this cluster, now known as RXJ1347.5-1145, a most interesting object for further cosmological studies.

8 de Junio de 1995: The ESO Council has just met at the ESO Headquarters in Garching during two days of intensive consultations. Among the important items on the agenda were the recent developments around the Very Large Telescope Project at Paranal, and also the possible membership of other countries.

7 de Junio de 1995: With the above title, and following the very successful events of the past two years [1], ESO again organises an "educational adventure" in 1995. It takes place within the framework of the "Third European Week for Scientific and Technological Culture", initiated and supported by the European Commission. This time ESO will invite about fifty 17-18 year old grammar school pupils with their teachers to try their skills at one of the world's most advanced astronomical telescopes.

2 de Junio de 1995: Versailles-Satory (France) May 31, 1995 - Giat Industries has just obtained a contract from the European Southern Observatory (ESO) for the construction of the primary and tertiary mirror supports and the positioning apparatus of the world's largest optical telescope. This contract, worth almost 140 million francs, represents over 100,000 hours of work. It was won by Gitech, a division of Giat Industries, in collaboration with the Sfim group, following an international competition between the largest European groups in the space field. Gitech is charged with the development of civil and military industrial equipment for the Giat Industries group, in particular in high technology fields.

19 de Abril de 1995: Today, Wednesday, 19 April 1995, the ESO Council [1] met in extraordinary session at the ESO Headquarters in Garching (Germany) to discuss the recent developments which have affected the operations of this Organisation in its host state, the Republic of Chile [2].

18 de Abril de 1995: Today, Tuesday, 18 April 1995, at the ESO Headquarters in Garching (Germany), Mr. Roberto Cifuentes, Plenipotentiary Ambassador representing the Government of the Republic of Chile, and the Director General of the European Southern Observatory, Professor Riccardo Giacconi, have signed a Supplementary, Interpretative and Amending Agreement to the Convention of 6 November 1963 which governs the relations between Chile and this International Organisation. This Agreement which in practice signifies a widening and strengthening of the cooperative relations between the Organisation and the Chilean scientific community will hereafter be submitted for ratification by the National Congress of the Republic of Chile (the Parliament) and by the ESO Council.

31 de Marzo de 1995: Yesterday, 30 March 1995 at 12:40 h Chilean time, a Chilean court official, Mr. Javier Jimenez, Receptor Indicial, accompanied by Chilean Carabinieros, forced an entry to the premises of ESO on Cerro Paranal without permission of ESO and without agreement between the Chilean Government and ESO, although warned that this act was in violation of the status of ESO as an international organization on the basis of the 1963 Convention and subsequent agreements between the Government of Chile and ESO.

20 de Febrero de 1995: ESO, the European Southern Observatory, in reply to questions raised by the international media, as well as an ongoing debate about the so-called "Paranal case" in Chilean newspapers, would like to make a number of related observations concerning its status and continued operation in that country [1].

1 de Febrero de 1995: The newest results of the associated investigations will be discussed at a scientific Workshop at ESO and presented to the media at a subsequent Press Conference on February 15, 1995.

2 de Diciembre de 1994: A joint EU/ESO Workshop [1] on the Teaching of Astronomy in Europe was held at the ESO Headquarters from November 25-30, 1994, under the auspices of the 1994 European Week for Scientific Culture. More than 100 teachers from secondary schools in 17 European countries participated together with representatives of national ministries and local authorities, as well as professional astronomers.

23 de Noviembre de 1994: A group of astronomers from the Aarhus University (Denmark) and the European Southern Observatory [2] have for the first time succeeded in detecting solar-type oscillations in another star. They observed the temperature of the bright northern star Eta Bootis during six nights with the 2.5-metre Nordic Optical Telescope at the Roque de los Muchachos observatory on the island of La Palma (Canary Islands) and were able to show that it varies periodically by a few hundredths of a degree. These changes are caused by pressure waves in the star and are directly dependent on its inner structure. A detailed analysis by the astronomers has shown that the observed effects are in good agreement with current stellar models. This is a most important, independent test of stellar theory.

15 de Noviembre de 1994: A joint Workshop of the European Union (EU) and the European Southern Observatory (ESO) will take place on November 25 - 30, 1994 under the auspices of the European Week for Scientific Culture. The Workshop is entitled "Astronomy: Science, Culture and Technology". It will bring together at the ESO Headquarters in Garching (Germany) more than 100 secondary school teachers and ministerial representatives from 17 European countries to discuss all aspects of this broad subject. It is the first and very visible part of a new, sustained effort to stimulate and modernize the teaching of the subjects of Astronomy and Astrophysics in European secondary schools. During the Workshop, the participants will experience the present state of this multi-disciplinary science in its most general context, that is as a human, long-term scientific and technological endeavour with great cultural implications. They will exchange views on how the various elements of Astronomy can best be utilized within the educational schemes of the individual countries, both as subjects in their own rights, and especially in support of many other items on the present teaching agenda.

31 de Octubre de 1994: This photo shows the faint image (arrow) of a new transneptunian object, discovered with the ESO 3.5-metre New Technology Telescope in October 1994. It is here seen in a negative reproduction (dark stars on white sky) of the CCD frame on which it was first noticed.

29 de Septiembre de 1994: During the past months, vast progress has been made in the construction of ESO's 16-metre equivalent Very Large Telescope (VLT). This major scientific and technological project aims at installing the world's largest optical telescope in the form of four interconnected telescopes with 8.2-metre mirrors on the Paranal mountain in the Chilean Atacama desert. It continues to be on schedule as it heads towards its completion, just after the year 2000.

9 de Agosto de 1994: The Council [1] of the European Southern Observatory has met in extraordinary session at the ESO Headquarters in Garching near Munich on August 8 and 9, 1994. The main agenda items were concerned with the recent developments around ESO's relations with the host state, the Republic of Chile, as well as the status of the organisation's main project, the 16-metre equivalent Very Large Telescope (VLT) which will become the world's largest optical telescope.

10 de Junio de 1994: As announced in an earlier Press Release (eso9408), a high-ranking ESO delegation visited Santiago de Chile during the week of 24 - 28 May 1994 to discuss various important matters of mutual interest with the Chilean Government. It consisted of Dr. Peter Creola (President of ESO Council), Dr. Catherine Cesarsky (Vice-President of ESO Council), Dr. Henrik Grage (Former Vice-President of ESO Council) and Professor Riccardo Giacconi (ESO Director General), the latter accompanied by his advisers.

27 de Mayo de 1994: Far down in the southern sky, in the constellation of Centaurus, a diffuse spot of light can be perceived with the unaided eye. It may be unimpressive, but when seen through a telescope, it turns out to be a beautiful, dense cluster of innumerable stars [1]. Omega Centauri, as this object is called, is the brightest of its type in the sky. We refer to it as a "globular cluster", due to its symmetric form. It belongs to our Milky Way galaxy and astrophysical investigations have shown that it is located at a distance of about 16,500 light-years (1 light-year = 9,460,000,000,000 km). Nobody knows for sure how many individual stars it contains, but recent estimates run into the millions. Most of these stars are more than 10,000 million years old and it is generally agreed that Omega Centauri has a similar age. Measurements of its motion indicate that Omega Centauri plows through the Milky Way in an elongated orbit. It is not easy to understand how it has managed to keep its stars together during such an extended period.

20 de Mayo de 1994: There are many signs that the upcoming collision between comet Shoemaker-Levy 9 and giant planet Jupiter is beginning to catch the imagination of the public. Numerous reports in the various media describe the effects expected during this unique event which according to the latest calculations will start in the evening of July 16 and end in the morning of July 22, 1994. (The times in this Press Release are given in Central European Summer Time (CEST), i.e., Universal Time (UT) + 2 hours. The corresponding local time in Chile is CEST - 6 hours.) Astronomers all over the world are now preparing to observe the associated phenomena with virtually all major telescopes. There will be no less than 12 different investigations at the ESO La Silla observatory during this period. This Press Release updates the information published in ESO PR 02/94 (27 January 1994) and provides details about the special services which will be provided by ESO to the media around this rare astronomical event.

18 de Mayo de 1994: The remote planet Pluto and its moon Charon orbit the Sun at a mean distance of almost 6,000 million kilometres, or nearly fourty times farther out than the Earth. During a recent investigation by an international group of astronomers [1], the best picture ever of Pluto and Charon [2] was secured with the European Space Agency's Faint Object Camera at the Hubble Space Telescope (HST). It shows the two objects as individual disks, and it is likely that further image enhancement will allow us to see surface features on Pluto.

6 de Mayo de 1994: The ESO Council, in its extraordinary session on 28 April 1994, among other matters discussed the relations with the Republic of Chile and the situation around Paranal mountain [1], the designated site for the ESO Very Large Telescope (VLT).

21 de Abril de 1994: ESO, the European Southern Observatory, in reply to questions raised by the media would like to clarify its position with regard to recent events which concern the land on which the Paranal mountain is situated.

20 de Abril de 1994: On Friday, 22 April 1994, a new science exhibition "Infinitos", arranged jointly by Lisboa'94, CERN and ESO, will open at the Museu de Electricidade on the waterfront of Lisbon, the capital of Portugal. In a series of spectacular displays, it illustrates man's current understanding of how the Universe works - from the tiniest structures of matter to the most far flung galaxies.

15 de Abril de 1994: Very difficult and time-consuming observations performed with the ESO 3.5-metre New Technology Telescope (NTT) in November 1993 by an international team of astronomers [1], indicate that up to 90 percent of the matter in a distant giant galaxy maybe of a kind that cannot be seen by normal telescopes.

18 de Febrero de 1994: Eight years after the passage of Comet Halley in early 1986, astronomers at the European Southern Observatory have succeeded in obtaining an image [1] of this famous object at a distance of no less than 2,820 million km from the Sun. The comet is now about as far away as giant planet Uranus. It recently passed the halfway mark towards the most distant point of its very elongated 76-year orbit. The image shows the 6 x 15 km avocado-shaped nucleus as an extremely faint point of light without any surrounding dust cloud. It appears that the surface is now completely frozen and the comet has ceased to emit dust and gas. This observation was made with the ESO 3.58 metre New Technology Telescope (NTT). It is by far the faintest and most distant image ever recorded of this comet.

3 de Febrero de 1994: On Wednesday, February 16, 1994, seven NASA and ESA astronauts and their spouses will spend a day at the Headquarters of the European Southern Observatory. They are the members of the STS-61 crew that successfully repaired the Hubble Space Telescope during a Space Shuttle mission in December 1993. This will be the only stop in Germany during their current tour of various European countries.

27 de Enero de 1994: Astronomers all over the world are preparing themselves for observations of a most unique event: during a period of six days in July 1994, at least 21 fragments of comet Shoemaker-Levy 9 will collide with giant planet Jupiter. At the European Southern Observatory, an intensive observational campaign with most of the major telescopes at La Silla is being organized with the participation of a dozen international teams of astronomers. This is the first time ever that it has been possible to predict such a collision. Although it is difficult to make accurate estimates, it is likely that there will be important, observable effects in the Jovian atmosphere.

27 de Enero de 1994: On 23 February 1994, it will be exactly seven years since the explosion of Supernova 1987A in the Large Magellanic Cloud [1] was first observed, at a distance of approx. 160,000 light-years. It was the first naked-eye supernova to be seen in almost four hundred years. Few events in modern astronomy have met with such an enthusiastic response by the scientists and this famous object has been under constant surveillance ever since. After several years of relative quiescence, things are now beginning to happen in the immediate neighbourhood of SN 1987A. Recent observations with the ESO 3.5 m New Technology Telescope (NTT) indicate that interaction between the stellar material which was ejected during the explosion and the surrounding ring-shaped nebulae has started. This signals the beginning of a more active phase during which the supernova is likely to display a number of new and interesting phenomena, never before observed.

20 de Diciembre de 1993: The ESO Council [1] took a number of important decisions in its December 1993 meeting. In particular, it unanimously agreed to proceed with the modified plan for the construction of the ESO Very Large Telescope at the Paranal mountain in Chile.

5 de Noviembre de 1993: A group of young people, aged between 16 and 18 years and with a special interest in astronomy, are about to experience two most exciting and formative weeks at the European Southern Observatory, first at the ESO Headquarters in Garching and then at the ESO La Silla Observatory in Chile.

20 de Agosto de 1993: This press release is only available in German.

20 de Agosto de 1993: This press release is only available in German.

29 de Junio de 1993: On June 25, 1993, Schott Glaswerke (Mainz, Germany) officially handed over to ESO the largest mirror blank ever made. Weighing 22,000 kilograms and with a diameter of 8.2 metres, the blank has a thickness of only 177 millimetres.

24 de Junio de 1993: The delegations of the Government of Chile and of the International Organisation ESO [1] report on the outcome of their discussions regarding the installation of the largest telescope in the world "The Very Large Telescope" and "Very Large Telescope Interferometer" (VLT /VLTI) at Cerro Paranal (in the Chilean region II — Antofagasta) and the clarification of the future relations between ESO and Chile. The object of these discussions was a closer cooperation between ESO and Chile to the mutual benefit of this country and the eight European member countries of ESO.

22 de Junio de 1993: ESO's Contribution to the European Week for Scientific Culture The European Southern Observatory is pleased to announce the launch of its new programme "Future Astronomers of Europe". It is organised in conjunction with the European Week for Scientific Culture (November 22 -27, 1993), with support from the Commission of the European Communities.

3 de Junio de 1993: The recent identification of the optical image of a pulsar in the Large Magellanic Cloud is a fine illustration of astronomy as a high-tech international science. It is the first extragalactic pulsar to be so identified and only the third radio pulsar, after those in the Crab and Vela nebulae in the Milky Way, for which this has been possible.

3 de Junio de 1993: Although astronomy is an exact natural science, chance sometimes plays an important role. The recent discovery during an otherwise routine observation of the hitherto brightest known double quasar [1] would not have been possible without some luck.

1 de Junio de 1993: On March 28, 1993, American astronomers David Jewitt and Jane Luu on Hawaii discovered a slow-moving minor planet of magnitude 23. More observations were made the following night, confirming the unusual motion and indicating that it is located at a very large distance from the Sun, possibly far beyond Pluto, the outermost known, major planet. It was given the preliminary designation 1993 FW (IAU Circular 5730)

14 de Mayo de 1993: ESO, the European Southern Observatory, in reply to questions raised by the media would like to clarify its position with regard to recent events which concern the relations between ESO and the Republic of Chile, the host state for the ESO observatories in the southern hemisphere.

27 de Marzo de 1993: The past decades have witnessed a dramatic increase in our knowledge of the Universe we live in. New instruments for astronomical observations and analysis are unveiling the secrets of deep space at an ever-increasing pace. Detailed studies of planets, stars, nebulae, galaxies and strange, exotic celestial objects have provided us with new insights into the formation, structure and evolution of our Universe.

29 de Enero de 1993: This photo is a composite of five exposures of Minor Planet no.~4179, also known as Toutatis, obtained with the 3.5-m ESO New Technology Telescope on December 21, 1992, by ESO-astronomer Jesper Storm. At this time, Toutatis was about 13 million km from the Earth, i.e. 33 times more distant than the Moon. On December 8, this Minor Planet passed within 3.6 million km from the Earth, but at that time it was not possible to observe it with ground-based optical telescopes, because it was situated between the Earth and the Sun. However, very good radar images were obtained which showed thecratered surface of the object.

3 de Diciembre de 1992: The Council of the European Southern Observatory [1], meeting at the ESO Headquarters in Garching on December 1-2, 1992, has decided to initiate a Programme by this organisation, aimed at supporting some of the scientifically most active and internationally highly esteemed astronomical institutes and research groups in Central and Eastern Europe (C&EE).

13 de Noviembre de 1992: Based on observations just obtained with the ESO New Technology Telescope at La Silla, a group of Italian astronomers [1] have securely identified the optical emission from the mysterious GEMINGA object. Although GEMINGA is the second strongest source of energetic gamma-rays in the sky, its optical image is extremely faint and the real nature of this strange object has long been a subject of debate. The present break-through became possible when the astronomers discovered and accurately measured the object's motion in the sky. As a consequence, GEMINGA is now believed to be the closest neutron star known to us, at a distance of no more than 300 light-years, possibly even smaller.

2 de Octubre de 1992: A new planet has just been found in the outer solar system. Although the observations do not yet allow an accurate determination of its orbit, it appears that it is situated about 6,000 million km away, outside the orbit of the outermost, known planet, Pluto. No other object has ever been found this far out in the solar system.

14 de Septiembre de 1992: An exhibition about Astronomy and the European organization for astronomy (ESO) will soon open at the Science and Technical Museum "Leonardo da Vinci" in Milan, Italy.

18 de Agosto de 1992: Minor Planet (4015) was discovered in 1979. It is of the Earth–crossing "Apollo" type and moves in an elongated orbit around the Sun; the period of revolution is 4.3 years.

13 de Agosto de 1992: Italian astronomers, working from the Astronomical Observatory in Trieste, have performed remote observations with the ESO 3.5 metre New Technology Telescope (NTT) at La Silla, Chile. This is the first time ever that such observations have been made directly from an astronomical institute in one of the ESO member countries. Quite unexpectedly, a "cosmic mirage", that is a gravitational lens in a distant cluster of galaxies, was found during these observations.

10 de Julio de 1992: This photo shows Comet Grigg-Skjellerup, as imaged by the ESO 3.6 m telescope at the La Silla Observatory in the early morning of July 10, 1992, just 15 hours before the Giotto encounter with this comet. The observation was made by Dr. Klaus Jockers from the Max-Planck-Institut für Aeronomie (Katlenburg-Lindau, Germany), and in the course of a special monitoring programme in support of the Giotto Extended Mission. The digital image was transmitted to the ESO Headquarters in Garching via the permanent satellite link, immediately following the observations. The photo is a composite of four one-minute red-sensitive exposures. The other objects in the field are galactic stars.

1 de Julio de 1992: This photo shows Comet Grigg-Skjellerup, which will be visited by the Giotto spacecraft of the European Space Agency (ESA) on July 10, 1992

10 de Junio de 1992: In its 67th meeting in Garching on June 4 and 5, 1992 the Council of ESO appointed Prof. Riccardo Giacconi as Director General for the period 1993-1997. He succeeds Prof. Harry van der Laan whose five year term ends this year.

13 de Mayo de 1992: This negative photo shows a small sky area in the direction of Comet Halley, obtained by ESO astronomers Alain Smette and Olivier Hainaut with the ESO 3.5-metre New Technology Telescope (NTT) in the morning of April 6, 1992

7 de Mayo de 1992: NASA's Hubble Space Telescope (HST) has revealed an unusual and fascinating new optical jet in the nucleus of the elliptical galaxy NGC 3862.

22 de Abril de 1992: The photo shows a model of the ESO 16-metre equivalent Very Large Telescope (VLT), as it will appear on the Paranal mountain in the Chilean Atacama desert towards the end of the present decade. The VLT will become the world's largest optical telescope when it is ready.

21 de Abril de 1992: On April 24, 1992, the French Minister for Research and Space, Professor Hubert Curien, will inaugurate a unique, new optical facility of R.E.O.S.C [2] , at Saint Pierre du Perray, near Paris. The delicate polishing of the giant mirrors for ESO's 16-metre equivalent Very Large Telescope (VLT) will take place here.

25 de Febrero de 1992: Messier 87 (M87) is a giant galaxy, situated right at the centre of one of the largest and nearest clusters of galaxies, the Virgo Cluster; its distance is about 50 million light-years) and several thousand galaxies belong to this cluster, but none is brighter and heavier than Messier 87. Already in 1918, photos showed the presence of a jet in M87, i.e. a long and thin feature, extending in a westerly direction from the centre of this galaxy. This jet bears witness to the violent processes at the centre of M87 and has led many astronomers to think that there is a giant black hole in there. Recent observations with the Hubble Space Telescope have strengthened this suspicion.

24 de Febrero de 1992: This photo shows the newly discovered minor planet 1992 AD which is the most distant in the solar system. It was obtained at the ESO La Silla Observatory on 5 February 1992. The telescope followed the planet whose 16.7 magnitude image is round; the stars in the field are seen as short trails. The diffuse trail at the upper right corner is that of a galaxy

5 de Febrero de 1992: The ESO 16-metre equivalent Very Large Telescope (VLT) [1] will be equipped with technologically advanced instruments that record the light collected by the large mirrors.

29 de Octubre de 1991: This is a ground-based photo of the first minor planet ever to be visited by a spacecraft. On October 29, 1991, the NASA spacecraft Galileo will pass minor planet no. 951 Gaspra on its way to Jupiter where it will arrive in December 1995. The distance from Gaspra to the Earth will be 410 million km at the time of the fly-by.

22 de Octubre de 1991: Observations with telescopes at the La Silla observatory have revealed that the image of an extremely distant quasar, known as Q1208+1011, actually consists of two images very close to each other. It is the most distant and also the brightest quasar ever observed to have a double image.

24 de Septiembre de 1991: ESO is now awarding a major contract for its Very Large Telescope (VLT) to the "AES Consortium" of three Italian companies. It concerns the construction of the main mechanical structures of the four 8-m VLT unit telescopes, each of which will weigh more than 440 tons and yet must be machined with sub-micron precision in order to allow astronomical observations of the highest quality.

24 de Septiembre de 1991: Observations with the 3.5-m ESO New Technology Telescope by a European group of astronomers have shown that a very compact object in an extraordinary binary star, known under the astronomical designation 88433, is most probably a neutron star and not a black hole, as previously believed by most scientists. Improved observation techniques have allowed a reliable determination of the mass of this object: it is now found to weigh less than the Sun and is therefore not massive enough to be a black hole.

16 de Julio de 1991: The lonely Atacama desert is a perfect place to study distant celestial bodies in the space around us. The following story shows how this may be done, not only through powerful astronomical telescopes at isolated mountain-top observatories [1], but also down on the barren desert plain in a much more direct way.

31 de Mayo de 1991: The ESO New Technology Telescope on La Silla has again proven its extraordinary abilities. Known since two years as the world's best optical telescope [1], it has now produced the "deepest" view into the distant regions of the Universe ever obtained with any ground-or space-based telescope. The new picture shows enormous numbers of extremely faint and remote galaxies whose images almost completely fill the field of view. Expressed in astronomical terms, the picture reaches beyond magnitude 29 [2].

26 de Abril de 1991: The decision to place the world's largest telescope, the ESO 16 metre equivalent Very Large Telescope (VLT) on the Paranal mountain in the Chilean Atacama desert [1], taken by the ESO Council on 4 December 1990, was today followed up by an important next step. During a small ceremony at the European Southern Observatory Headquarters in Garching, two major contracts were signed which will together define the future shape of the VLT Observatory and its infrastructure.

22 de Febrero de 1991: It was early in the morning of Tuesday, February 12, and ESO astronomers Olivier Hainaut and Alain Smette [1] did not know what to believe. Observing with the Danish 1.54-metre telescope at the La Silla observatory, they had just finished a one-hour exposure of a small sky field in the constellation of Hydra (the Water Snake). This work was part of the ESO monitoring programme of famous Comet Halley and the astronomers felt that something was quite wrong.

6 de Febrero de 1991: A test run for the manufacture of mirror blanks in the 8-metre class, for use in the world's largest optical telescope, the ESO 16-m equivalent Very Large Telescope (VLT), has been successfully performed at Schott in Mainz, Germany [1]. The test blank had a diameter of 8.6 metres and a surface area of more than 55 metres squared. This is the first time that has been possible to cast such a large glass-ceramic blank in one piece. To accomplish this impressive feat, Schott has developed a number of new technological procedures.

17 de Enero de 1991: Acting on information received from Danish scientists working with an X-ray telescope on a Soviet satellite, astronomers at the ESO La SiIla observatory in Chile have discovered a strange new star in the southern constellation of Musca (the Fly). Preliminary observations with the ESO 3.5-m New Technology Telescope indicate that the object is a nova, most probably a small, very dense star in a binary system whose brightness in a dramatic event has suddenly increased about 1000 times. The available optical and X-ray observations point to a quite unusual object.

4 de Diciembre de 1990: The Council of the European Southern Observatory, in session today at the ESO Headquarters in Garching near Munich, unanimously decided that the world's largest optical telescope, the 16-metre equivalent Very Large Telescope, shall be placed on Cerro Paranal [1], an isolated mountain top at 2664 m altitude in the central part of Chile's Atacama desert, some 130 kilometres south of the town of Antofagasta and 12 kilometres from the Pacific coast.

9 de Noviembre de 1990: A very large, white spot has recently appeared on the giant planet Saturn [1]. It is probably a great storm in the planet's atmosphere, which has been initiated by upwelling of clouds from the lower layers into the uppermost regions. The spot began as a small, white feature in Saturn's northern hemisphere and has since developed rapidly so that it now appears to completely encircle the planet's equatorial regions. "Great White Spots" have been seen on Saturn in 1876, 1903, 1933 and 1960 (see below), but the present one seems to be the biggest of them all.

31 de Octubre de 1990: Observing with the ESO New Technology Telescope, three European astronomers have discovered two previously unknown celestial objects which are seen in the direction of the mysterious centre of our galaxy, the Milky Way. One of the new objects has a comparatively blue colour and appears to be the actual Galactic Centre, at a distance of about 28 000 light-years. It has required a telescope with the penetrating power of the NTT to see through the dense, interstellar dust clouds (which effectively hide the central area from our view) in order to obtain the first optical image of the Galactic Centre.

24 de Octubre de 1990: Astronomers working at the ESO La Silla observatory have just discovered the most distant "normal" galaxy known so far. It has been given the designation G 0102 - 190 and its distance is so great that the light we observe from it was emitted when the Universe was only one third as old as now [1].

29 de Septiembre de 1990: By decree of the International Astronomical Union, a newly discovered minor planet (asteroid) in the solar system has been given the name Portugal, honouring this European country.

27 de Septiembre de 1990: A long-term astronomical study of spiral galaxies, initiated almost a decade ago at the European Southern Observatory, has recently produced intriguing results about the presence of cold matter in the Universe. They have a direct bearing on the so-called "missing mass" problem, one of the major unsolved riddles in astronomy.

25 de Septiembre de 1990: These impressive photos of Comet Levy (1990c), one of the brightest comets in recent years, were obtained with the ESO 1-metre Schmidt telescope at the ESO La Silla Observatory, on September 12 and 14, 1990. On these dates, the comet was 104 and 111 million kilometres from the Earth and 179 and 176 million kilometres from the Sun, respectively. It will reach its perihelion (the point in the orbit which is closest to the Sun) on October 24.

26 de Julio de 1990: Famous Comet Halley, now receding from the Sun after its perihelion passage in early 1986, has recently entered into a state of hibernation which will last until shortly before the next passage in 2062.

13 de Junio de 1990: Most of the dust that is ejected from a comet's nucleus (i.e. the "dirty snowball" at its centre) assembles in a thin “sheet'' near the orbital plane in which the comet moves around the sun. This sheet is very thin and is difficult to observe unless it is viewed directly from the side. On June 6, 1990, the Earth crossed the orbital plane of Comet Austin, allowing such a unique, side-on view.

23 de Mayo de 1990: With the help of "adaptive optics," a revolutionary optical concept (eso8908), infrared astronomical images have been obtained with the ESO 3.6 m telescope at the La Silla observatory which are as sharp as they would be if the telescope were situated in space. This is the first time in astronomy that a ground-based telescope of this size has been able to directly register during long time periods stellar images with a sharpness that corresponds to the theoretically possible limit.

9 de Abril de 1990: Paris, Brussels, Vienna and Copenhagen were some of the stations for ESO's travelling astronomy exhibition. Now this exhibition can be seen for the first time in Switzerland, where CERN's MICROCOSM exhibition has opened its doors for a detailed view at the World of stars and galaxies.

2 de Marzo de 1990: Professional and amateur astronomers all over the world are excited about the prospects of seeing a really bright comet during the coming months. A newly discovered comet, known by the name of the amateur who first saw it, is now getting brighter each day. Observations are made almost every night at the ESO La Silla Observatory and elsewhere in order to follow the development of the comet and also to try to predict the maximum brightness which the comet will reach by mid-April this year.

6 de Febrero de 1990: In the presence of a distinguished audience of ministers and high-ranking officials, as well as representatives of European industry and scientists from the member states, the European Southern Observatory today officially inaugurates its revolutionary 3.5-metre New Technology Telescope (NTT).

26 de Enero de 1990: The California Institute of Technology (Caltech) of Pasadena, California, U.S.A. and the European Southern Observatory have concluded an agreement by which ESO will undertake the responsibility of producing high-quality copies of photographic sky survey plates obtained with the Palomar 40-inch Oschin Telescope and to distribute the resulting photographic atlas [1].

5 de Enero de 1990: Is there - or is there not - a pulsar in Supernova 1987A? This is one of the main enigmas in current astrophysical research, and nearly three years after the explosion of the first naked-eye supernova (see eso8704, eso8705, eso8706, eso8711 and eso8802) in four hundred years, the answer is still not known.

26 de Octubre de 1989: An old dream of ground-based astronomers has finally come true, thanks to the joint development of a revolutionary new technique, adaptive optics, by ESO and ONERA [1], LdM [2] and Observatoire de Paris in France.

25 de Julio de 1989: The European Southern Observatory and R.E.O.S.C. Optique (Recherches et études d'optique et de sciences connexes), located at Ballainvilliers near Paris, France, have reached agreement on a contract for the polishing of four giant mirror blanks for the ESO Very Large Telescope (VLT) (see eso8717 and eso8808).

6 de Julio de 1989: Recent studies at the European Southern Observatory indicate that the formation of a new star is a dramatic process which may be more complex than most astronomers believed only a few years ago.

30 de Mayo de 1989: On May 11, 1989, Richard M. West at the ESO Headquarters in Garching, Fed.Rep.Germany, found a new comet in a photographic plate obtained on March 14 by night assistant Guido Pizarro with the 1-m Schmidt at the ESO La Silla Observatory. The blue-sensitive plate was exposed during 60 minutes and was centered in the southern constellation of Libra.

11 de Mayo de 1989: "First Light" with the ESO New Technology Telescope (NTT) was obtained on March 23, 1989 (eso8903) during conditions of exceptionally good "seeing'' and the first images are probably the sharpest ever obtained with a large, ground-based telescope. A full account of the associated events will appear in the June 1989 issue of the ESO Messenger.

23 de Marzo de 1989: Early this morning, and during superb atmospheric conditions, the 3.5 m ESO New Technology Telescope (NTT) produced its first astronomical images. They completely satisfy the high expectations towards this revolutionary high-tech telescope, the first of its kind in the world. This important milestone was passed less than seven years after the start of the NTT project in 1982 and at the end of a four-year construction phase (various aspects of the New Technology Telescope have been described in eso8801 and eso8805).

24 de Febrero de 1989: A recent announcement of the discovery of a pulsar in Supernova 1987A in the Large Magellanic Cloud has excited the world-wide astronomical community. New observations at the La Silla Observatory by a group of European astronomers from the Max Planck Institute for Extraterrestrial Physics and the European Southern Observatory, however, do not confirm the reality of this object. More observations are now needed to settle this important question.

30 de Enero de 1989: Everybody knows the Crab Nebula - that famous object in the northern constellation Taurus (The Bull). It is the remnant of a supernova explosion in the year 1054 and has been studied with all available astronomical techniques. But this nebula does not really resemble the animal whose name it carries! Whoever attached this name to it by the middle of the last century must have had a well developed imagination. Now a "real crab'' has been discovered, a nebula in the southern constellation of Centaurus (The Centaur), which from its appearance on recent pictures made with telescopes at the La Silla Observatory would seem to have more right to associate with crustaceans. To avoid confusion, astronomers now refer to the new object as the "Southern Crab".

8 de Diciembre de 1988: Reinhold Häfner, visiting astronomer at the ESO La Silla Observatory, got his life's surprise when the star on the screen in front of him suddenly was gone. All the other stars were still visible, but this particular one had simply vanished.

12 de Septiembre de 1988: After a period of intense negotiation, the European Southern Observatory and Schott Glaswerke, Mainz (F.R.Germany) reached agreement about the delivery of four giant mirror blanks for the ESO Very Large Telescope (VLT) (ESO8716). The blanks will be made of Zerodur, a glass ceramic material. Each will have a diameter of 8.2 metres, an area of more than 50 square metres and a thickness of only 17.5 centimetres.

9 de Septiembre de 1988: The most distant, individual star ever recorded was detected with a telescope at the ESO La Silla observatory on August 9, 1988. The object is an exploding star, a supernova, and is situated in an inconspicuous galaxy, itself a member of a distant cluster of galaxies. Additional observations indicate that the cluster, known as AC118, is at a distance of about 5 billion light-years (1 billion = 1000 million). Thus this supernova explosion occurred 5 billion years ago, or about the time when the Sun and the planets were born. Ever since then, the light emitted by this event has been travelling towards us, only arriving here now. It is the most distant supernova (ESO8802) observed so far.

28 de Julio de 1988: Thanks to observations performed under near-perfect conditions at the La Silla observatory, it has been possible to show that the image of a distant quasar consists of no less than four components. Most appropriately, the object has now become known as the cloverleaf quasar. The peculiar image is due to the effect of "gravitational lensing", a phenomenon predicted by Einstein's General Theory of Relativity and explained at the end of this Press Release.

14 de Julio de 1988: On the occasion of the successful completion of the optical figuring of the 3.58 m primary NTT mirror, the European Southern Observatory and Carl Zeiss, FRG, organize a Press Conference on Wednesday, July 13, 14.00 hours, at the Zeiss works in Oberkochen, near Stuttgart, FRG. There will be an opportunity to see the finished mirror on its computer controlled support system and information will be provided about the successful tests of the world's first, large active optics telescope.

8 de Julio de 1988: A unique picture of Comet Halley has just been obtained by three astronomers with a telescope at the ESO La Silla observatory. An exposure time of almost 12 hours was necessary to show the structure of the famous comet in some detail at the present, very large distance of 1250 million kilometres.

19 de Mayo de 1988: The most massive stars may be less heavy than thought before. Recent observations with two telescopes at the ESO La Silla observatory have now shown that a star in the Large Magellanic Cloud, long believed to be one of the most massive in existence, is in fact multiple and consists of a very compact cluster of hot, young stars. This discovery may have important implications for the theory of stellar birth and the determination of distances in the Universe.