10 years of adaptive optics
Sunday, 27 November 2011 00:12
25 November 2011 marks the 10th anniversary of NACO, the first adaptive optics system to be installed on the
ESO Very Large Telescope (VLT). NACO’s ultra-sharp vision has greatly contributed to the major discoveries made with
the VLT. NACO, short for NAOS-CONICA, was the first adaptive optics instrument to be installed on the VLT, in 2001.
By compensating for turbulence in the Earth’s atmosphere, NACO greatly improved the telescope’s
image sharpness and scientific potential. The instrument, developed by French and German consortia with the collaboration
of ESO, was the first of a series of adaptive optics instruments that would be installed on the VLT Unit Telescopes.
Some of NACO’s first targets were planets and moons in the Solar System. These observations provided the
first detailed maps of Titan’s weather and surface (eso0505) and infrared images of Io’s powerful volcanoes (eso0204).
NACO has also observed planets orbiting other stars. In 2004 it provided the first-ever direct image of an exoplanet (eso0428).
By 2010 NACO had even been able to directly follow the motion of an exoplanet as it moved from one side of the
star beta Pictoris to the other (eso1024). The instrument has also provided the first-ever spectrum of a directly observed
exoplanet, allowing astronomers to study the planet’s atmosphere (eso1002). NACO has also been used to peer into the
centre of our galaxy, its infrared vision being able to see through the dense clouds of dust along the line of sight. It was
used to make a series of very precise observations of the orbits of stars around the black hole since 2002 (see eso0226 and
These crucial observations proved conclusively that there was a supermassive black hole at the centre of the
Milky Way, This work has been rated as the first of ESO’s most significant scientific achievements to date (see ESO
Top 10 science discoveries). Adaptive optics technology has continued to evolve, and a new generation of instruments is under
construction or being planned to ensure that even better facilities will be available on the VLT in future. Looking into the
next decade yet more advanced adaptive optics systems are under development for ESO's European Extremely Large Telescope,