A new instrument, SIMBA ("SEST IMaging Bolometer Array"), has been installed at the Swedish-ESO Submillimetre Telescope (SEST) at the ESO La Silla Observatory in July 2001. It records astronomical images at a wavelength of 1.2 mm and is able to quickly map large sky areas. In order to achieve the best possible sensitivity, SIMBA is cooled to only 0.3 deg above the absolute zero on the temperature scale.
SIMBA is the first imaging millimetre instrument in the southern hemisphere. Radiation at this wavelength is mostly emitted from cold dust and ionized gas in a variety of objects in the Universe. Among other, SIMBA now opens exciting prospects for in-depth studies of the "hidden" sites of star formation, deep inside dense interstellar nebulae. While such clouds are impenetrable to optical light, they are transparent to millimetre radiation and SIMBA can therefore observe the associated phenomena, in particular the dust around nascent stars.
This sophisticated instrument can also search for disks of cold dust around nearby stars in which planets are being formed or which may be left-overs of this basic process. Equally important, SIMBA may observe extremely distant galaxies in the early universe, recording them while they were still in the formation stage.
Various SIMBA images have been obtained during the first tests of the new instrument. The first observations confirm the great promise for unique astronomical studies of the southern sky in the millimetre wavelength region.
These results also pave the way towards the Atacama Large Millimeter Array (ALMA), the giant, joint research project that is now under study in Europe, the USA and Japan.
The full account of this work, with four photos and all weblinks, is available as ESO PR 20/01 at URL: http://www.eso.org/outreach/press-rel/pr-2001/pr-20-01.html