Only the first two hours of the night were usable before high humidity, clouds, fog and finally light rain ended the night. The mountain created its own weather as Tucson stayed mostly clear, but humid, just a few miles away. The seeing was highly variable and bad (2-3 arcsec). Only four bright blazars could be observed, but this included multiple observations of CTA102, which continues its epic outburst.
Campaign 90 is now finally finished and was marked by a lot of bad weather.
But still, given that it spanned 11 long nights, over 100 blazar observations
were obtained despite the fact that there was only one(!) night when
observations were made throughout the entire night without interruptions.
There is now a quick transition over to the Bok Telescope
for the start of Campaign 91 in just four days. With luck, the CTA102
outburst will continue to be followed through full moon from Kitt Peak, AZ.