MUSE (the Multi-Unit Spectroscopic Explorer) is the most powerful optical 3D spectrograph for astrophysics to date. With only one sky image, MUSE can simultaneously register more than 90,000 spectra of astronomical objects. The large number of spectra is realized through a modular design of the instrument, featuring 24 identical integral field units (IFU), each consisting of an image slicer, a spectrograph, and a CCD detector. Since 2014 it is operated at the Very Large Telescope (VLT) in the Chilean Atacama Desert. 2017 a module for atmospheric correction using adaptive optics was added. The last upgrade in 2018 finally added a high-resolution mode that enables spatial resolution comparable to the HST.
Contributions from AIP
The instrument was designed, built, and tested in Europe, by a consortium of 7 institutes, led by the Observatoire de Lyon (CRAL). Potsdam contributed the calibration unit of MUSE. AIP also performed the acceptance tests of the 24 detectors. The comprehensive data reduction software that converts the raw data into datacubes that form the base for all scientific analysis was developed at AIP as well.
The major science case for MUSE is to discover distant, high-redshift galaxies and to measure their properties. Further interests of AIP astronomers are the spectroscopic analyses of individual objects in nearby galaxies and to study galaxy mergers. In general, the ability of MUSE to detect even the faintest line emission or to resolve it at high spatial resolution has led to breakthroughs in various fields.