MISTRAL is a new-generation receiver for observations at millimeter wavelengths, built as part of the recent project to upgrade the Sardinia Radio Telescope for the study of the high-frequency radio universe. The main features of this instrument are the very high number of detectors cooled  to temperatures close to absolute zero and a dedicated cold optical system, which allow for extremely sharp images. MISTRAL made its “first light” by observing three different celestial objects: the Orion Nebula, the radio lobes of the supermassive black hole in the galaxy M87, and the supernova remnant Cassiopeia A. These images represent the first scientific observations at 90 GHz ever obtained using the SRT.

M42: The left panel shows the image of the Orion nebula (M42). Right: a wider-field image obtained by the Hubble Space Telescope.

M87: Image of the radio source around M87 whose active nucleus contains a now famous supermassive black hole.

Cassiopeia A: Image of the supernova remnant Cassiopeia A. The expanding gas shell is visible in its entirety.

Credits: MISTRAL commissioning team; NASA, ESA, and The Hubble Heritage Team (STScI/AURA); Sloan Digital Sky Survey