DIMM Testing in Tucson

LSST AI&V and Commissioning are in the process of receiving two Differential Image Motion Monitors (DIMMs), one portable DIMM on a tripod (pictured here) and one permanent one that will be installed on a tower on calibration hill. Systems such as these observe a single bright star and monitor the stability of the atmosphere through two columns of air simultaneously. The correlation of the two “star" measurements give a good estimation of various parameters of atmospheric turbulence, including astronomical “seeing”.