Comunicati stampa

05 Novembre 1986: For the first time, an accurate and direct determination of the diameters of the outermost planet Pluto and its moon, Charon, has been made. On the basis of measurements of light changes during eclipses, Pluto was found to have a diameter of 2200±140 km. Charon is approximately half the size; the diameter is 1160±100 km. Charon moves in an almost perfectly circular orbit around Pluto; the orbital period is 6.38 days and the mean distance is 19400 km.

04 Ottobre 1986: The ESO Very Large Telescope (VLT) project [1] has passed an important milestone on its way towards realization. This week, more than 80 leading scientists and engineers from the ESO member countries (and beyond) made a detailed assessment of this ambitious project, which aims at the construction of the world's largest optical telescope. There was unanimous agreement that the present concept is near the optimal, that it is technologically feasible and can be realized within approximately 10 years after funding has been decided upon, and that it will allow European astronomers to perform new and spectacular investigations of the universe, unparalleled elsewhere. Completion is aimed at in 1997 but part of the VLT may become operational already in 1993.

13 Maggio 1986: Detailed observations of a bright supernova in the peculiar galaxy NGC 5128 = Centaurus A, have led astronomers at the European Southern Observatory to believe that this galaxy is much closer to us than previously thought. It is the nearest, strongly radio-emitting galaxy and is as such an object of crucial importance in modern astrophysical research. The revised distance is 7 - 10 million light years or only 3 - 4 times farther away than the Andromeda Nebula. Cen A may therefore even be an outlying member of the Local Group. The total radio emission energy corresponds to the conversion to pure energy (annihilation) of a mass equal to 10.000 suns.

06 Marzo 1986: This spectacular image of Comet Halley, rising above the eastern horizon, was obtained at the La Silla observatory during the morning of February 22. It was made by superposing 6 exposures (total 9 min.) with the wide-field CCD camera which was specially designed for the study of Comet Halley. The image measures 5.5 x 9 degrees across and covers the 500 - 1100 nm spectral region (green near infrared). Each pixel (image element) measures 31 x 31 arc-seconds.

03 Marzo 1986: After several years of intensive studies, the European Southern Observatory now releases information to the public about its 16 metre telescope project. The concept here shown is the result of an extensive collaboration between European science and industry.

26 Febbraio 1986: 23 February was the last morning when Comet Halley could be seen in a dark sky. During the next two weeks, the moonshine will hamper further detailed observations of the incredibly complicated tail structure which was recently detected at the European Southern Observatory on La Silla.

18 Febbraio 1986: After the successful recovery of Comet Halley on 15 February, at the European Southern Observatory (ESO), observations have been made at the ESO La Silla Observatory every morning since. Accurate positions of the comet continue to be measured and transmitted within a few hours to the spacecraft centers in Darmstadt, Moscow, Tokyo and Pasadena. This is an important contribution to the accurate navigation of the five spacecrafts, including the European Space Agency's GIOTTO, now heading towards an encounter with Halley in early March.

16 Febbraio 1986: The first observation of Comet Halley after its passage behind the Sun was made at ESO La Silla by ESO Staff Astronomer R.M. West and Belgian astronomer H. Debehogne.

21 Gennaio 1986: An important contract was signed today in Milan, Italy between the European Southern Observatory and INNSE Innocenti Santeustacchio. It concerns the construction of a large astronomical telescope which will become the technologically most advanced in the world when it enters into operation in 1988.

13 Gennaio 1986: ESO has established a new service, which will from now on handle all public relations matters. It is located at the ESO Headquarters in Garching, FRG and can be reached as indicated below.

17 Dicembre 1985: Comet Halley was photographed with the ESO 1 metre Schmidt telescope at La Silla on 1985 December 9. The exposure was 10 min on a blue-sensitive emulsion. The telescope was guided on the moving comet. The stars in the field are therefore seen as short trails.