eso0313 — Organisation Release
Sharper and Deeper Views with MACAO-VLTI
13 May 2003: On April 18, 2003, a team of engineers from ESO celebrated the successful accomplishment of "First Light" for the MACAO-VLTI Adaptive Optics facility on the Very Large Telescope (VLT) at the Paranal Observatory (Chile). This is the second Adaptive Optics (AO) system put into operation at this observatory, following the NACO facility. The achievable image sharpness of a ground-based telescope is normally limited by the effect of atmospheric turbulence. However, with Adaptive Optics (AO) techniques, this major drawback can be overcome so that the telescope produces images that are as sharp as theoretically possible, i.e., as if they were taken from space. The acronym "MACAO" stands for "Multi Application Curvature Adaptive Optics" which refers to the particular way optical corrections are made which "eliminate" the blurring effect of atmospheric turbulence. The MACAO-VLTI facility was developed at ESO. It is a highly complex system of which four, one for each 8.2-m VLT Unit Telescope, will be installed below the telescopes (in the Coudé rooms). These systems correct the distortions of the light beams from the large telescopes (induced by the atmospheric turbulence) before they are directed towards the common focus at the VLT Interferometer (VLTI). The installation of the four MACAO-VLTI units of which the first one is now in place, will amount to nothing less than a revolution in VLT interferometry. An enormous gain in efficiency will result, because of the associated 100-fold gain in sensitivity of the VLTI. Put in simple words, with MACAO-VLTI it will become possible to observe celestial objects 100 times fainter than now . Soon the astronomers will be thus able to obtain interference fringes with the VLTI of a large number of objects hitherto out of reach with this powerful observing technique, e.g. external galaxies. The ensuing high-resolution images and spectra will open entirely new perspectives in extragalactic research and also in the studies of many faint objects in our own galaxy, the Milky Way. During the present period, the first of the four MACAO-VLTI facilties was installed, integrated and tested by means of a series of observations. For these tests, an infrared camera was specially developed which allowed a detailed evaluation of the performance. It also provided some first, spectacular views of various celestial objects, some of which are shown here.