Lehdistötiedotteet 1991

29. lokakuuta 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. lokakuuta 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. syyskuuta 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. syyskuuta 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. heinäkuuta 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. toukokuuta 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. huhtikuuta 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. helmikuuta 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. helmikuuta 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. tammikuuta 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.