ESO and its partners are celebrating the very successful
accomplishment of “First Light” for NAOS-CONICA, the first adaptive
optics instrument to be installed at the VLT on Paranal. The first
results are excellent and have shown the great potential of this new
facility. An account of this event, with numerous photos and a video
clip, is now available as ESO Press Release 25/01 at:

You will find below the summary of this PR, also available at

with a list of the PR Photos, etc.

A team of astronomers and engineers from French and German research
institutes and ESO at the Paranal Observatory is celebrating the
successful accomplishment of “First Light” for the NAOS-CONICA
Adaptive Optics facility. With this event, another important milestone
for the Very Large Telescope (VLT) project has been passed.

Normally, the achievable image sharpness of a ground-based telescope
is limited by the effect of atmospheric turbulence. However, with the
Adaptive Optics (AO) technique, this drawback can be overcome and the
telescope produces images that are at the theoretical limit, i.e., as
sharp as if it were in space.

Adaptive Optics works by means of a computer-controlled, flexible
mirror that counteracts the image distortion induced by atmospheric
turbulence in real time. The larger the main mirror of the telescope
is, and the shorter the wavelength of the observed light, the sharper
will be the images recorded.

During a preceding four-week period of hard and concentrated work, the
expert team assembled and installed this major astronomical instrument
at the 8.2-m VLT YEPUN Unit Telescope (UT4). On November 25, 2001,
following careful adjustments of this complex apparatus, a steady
stream of photons from a southern star bounced off the
computer-controlled deformable mirror inside NAOS and proceeded to
form in CONICA the sharpest image produced so far by one of the VLT

With a core angular diameter of only 0.07 arcsec, this image is near
the theoretical limit possible for a telescope of this size and at the
infrared wavelength used for this demonstration (the K-band at 2.2
micron). Subsequent tests reached the spectacular performance of 0.04
arcsec in the J-band (wavelength 1.2 micron).

“I am proud of this impressive achievement”, says ESO Director General
Catherine Cesarsky. “It shows the true potential of European science
and technology and it provides a fine demonstration of the value of
international collaboration. ESO and its partner institutes and
companies in France and Germany have worked a long time towards this
goal – with the first, extremely promising results, we shall soon be
able to offer a new and fully tuned instrument to our wide research

The NAOS adaptive optics corrector was built, under an ESO contract,
by Office National d’Etudes et de Recherches Aerospatiales (ONERA),
Laboratoire d’Astrophysique de Grenoble (LAOG) and the DESPA and
DASGAL laboratories of the Observatoire de Paris in France, in
collaboration with ESO. The CONICA infra-red camera was built, under
an ESO contract, by the Max-Planck-Institut fuer Astronomie (MPIA)
(Heidelberg) and the Max-Planck Institut fuer Extraterrestrische
Physik (MPE) (Garching) in Germany, in collaboration with ESO.

The present event happens less than four weeks after “First Fringes”
were achieved for the VLT Interferometer (VLTI) with two of the 8.2-m
Unit Telescopes. No wonder that a spirit of great enthusiasm reigns at

Information for the media: ESO is producing a Video News Release (ESO
Video News Reel No. 13) with sequences from the NAOS-CONICA “First
Light” event at Paranal, a computer animation illustrating the
principle of adaptive optics in NAOS-CONICA, as well as the first
astronomical images obtained. In addition to the usual distribution,
this VNR will also be transmitted via satellite Friday 7 December 2001
from 09:00 to 09:15 CET (10:00 to 10:15 UT) on “Europe by
Satellite”. These video images may be used free of charge by
broadcasters. Satellite details, the script and the shotlist will be
on-line from 6 December on the ESA TV Service Website Also a pre-view Real Video Stream of the
video news release will be available as of that date from this URL.

This Press Release includes the following video and photos:

Video Clip 07/01: Various video scenes related to the NAOS-CONICA
“First Light” Event (from ESO Video News Reel No. 13).

PR Photo 33a/01: NAOS-CONICA “First light” image of an 8-mag star.

PR Photo 33b/01: The moment of “First Light” at the YEPUN Control

PR Photo 33c/01: Image of NGC 3603 (K-band) area (NAOS-CONICA).