  The TurLab facility is a laboratory, equipped with a 5 m diameter and 1 m
depth rotating tank, located in the fourth basement level of the Physics
Department of the University of Turin. In the past years, we have used the
facility to perform experiments related to the observations of Extreme Energy
Cosmic Rays (EECRs) from space using the fluorescence technique for JEM- EUSO
missions with the main objective to test the response of the trigger logic. In
the missions, the diffuse night brightness and artificial and natural light
sources can vary significantly in time and space in the Field of View (FoV) of
the telescope. Therefore, it is essential to verify the detector performance
and test the trigger logic under such an environment. By means of the tank
rotation, a various terrestrial surface with the different optical
characteristics such as ocean, land, forest, desert and clouds, as well as
artificial and natural light sources such as city lights, lightnings and
meteors passing by the detector FoV one after the other is reproduced. The fact
that the tank located in a very dark place enables the tests under an optically
controlled environment. Using the Mini-EUSO data taken since 2019 onboard the
ISS, we will report on the comparison between TurLab and ISS measurements in
view of future experiments at TurLab. Moreover, in the forthcoming months we
will start testing the trigger logic of the EUSO-SPB2 mission. We report also
on the plans and status for this purpose.
