16 Feb 2022

An international team of astronomers led by Violeta Gámez Rosas (Leiden University) has observed a supermassive black hole hidden in a ring of dust. This discovery fits the idea that the so-called active centers of galaxies are much more similar than observations show, because the viewing angle from Earth causes distortions. The research was done with the MATISSE instrument, co-developed in the Netherlands, which combines infrared light from four European Very Large Telescopes (VLT) in Chile.

MATISSE is the acronym for Multi AperTure mid-Infrared SpectroScopic Experiment. MATISSE not only couples the light from the VLT, but also analyzes it. MATISSE was created specifically for infrared light with wavelengths between 3 micrometers and 13 micrometers. Infrared light is also created when something gives off heat. Therefore, MATISSE is cooled to minus 241 degrees Celsius so the instrument itself does not interfere with the measurements.

Nanometer precision

Netherlands Research School for Astronomy (NOVA) built all the lenses and mirrors in the cooled part of MATISSE together with the Dutch space industry. The Netherlands had gained experience while developing its forerunner MIDI, which could link two telescopes instead of four.

The heart where the beams of the four VLT telescopes converge, consists of two aluminum boxes that are almost a meter in size. These boxes are filled to the brim with hundreds of optical components, dozens of sensors and dozens of tiny motors. Most of the components work with nanometer precision or even higher.