eso0105 — Organisationsmeddelande
New Paranal Views
26 januari 2001
Last year saw very good progress at ESO's Paranal Observatory, the site of the Very Large Telescope (VLT). The third and fourth 8.2-metre Unit Telescopes, MELIPAL and YEPUN had "First Light," while the first two, ANTU and KUEYEN, were busy collecting first-class data for hundreds of astronomers. Meanwhile, work continued towards the next phase of the VLT project, the combination of the telescopes into the VLT Interferometer. The test instrument, VINCI is now being installed in the VLTI Laboratory at the centre of the observing platform on the top of Paranal.
Below is a new collection of video sequences and photos that illustrate the latest developments at the Paranal Observatory. The were obtained by the EPR Video Team in December 2000. The photos are available in different formats, including "high-resolution" that is suitable for reproduction purposes. A related ESO Video News Reel for professional broadcasters will soon become available and will be announced via the usual channels.
The VLT Interferometer
The Delay Lines consitute a most important element of the VLT Interferometer. At this moment, two Delay Lines are operational on site. A third system will be integrated early this year.
The VLTI Delay Line is located in an underground tunnel that is 168 metres long and 8 metres wide. This configuration has been designed to accommodate up to eight Delay Lines, including their transfer optics in an ideal environment: stable temperature, high degree of cleanliness, low levels of straylight, low air turbulence.
The positions of the Delay Line carriages are computed to adjust the Optical Path Lengths requested for the fringe pattern observation. The positions are controlled in real time by a laser metrology system, specially developed for this purpose. The position precision is about 20 nm (1 nm = 10 -9 m, or 1 millionth of a millimetre) over a distance of 120 metres. The maximum velocity is 0.50 m/s in position mode and maximum 0.05 m/s in operation. The system is designed for 25 year of operation and to survive earthquake up to 8.6 magnitude on the Richter scale.
The VLTI Delay Line is a three-year project, carried out by ESO in collaboration with Dutch Space Holdings (formerly Fokker Space) and TPD-TNO.
The "NTT Peak"
The "NTT Peak" is a mountain top located about 2 km to the north of Paranal. It received this name when ESO considered to move the 3.58-metre New Technology Telescope from La Silla to this peak.
The possibility of installing the 4-metre VISTA telescope (cf. eso0003) on this peak is now being discussed.