Contributions by Gemini staff
News for Users
The current semester at Gemini South has had its ups and downs:
poor weather conditions have prevented almost all scheduled
observations in May; but on the bright side, preventative
maintenance on FLAMINGOS-2 is complete. In Hawai‘i, repairs to
the Gemini North wind blind will start in early July. We’ve made
several major changes to the new 2016B Observing Tool, and we
invite you to contribute to the Gemini community by registering
for the Gemini Data Reduction User Forum.
Figure 1.
Gemini South’s shutters
remained closed for
most of May 2016,
due to persistent poor
weather.
Photo credit: Sandra
Romero, Gemini
A Month to Forget
May 2016 may have been the worst month ever for weather
at Gemini South on Cerro Pachón in Chile. In an average year,
May is the first of five “bad” months, with weather loss usually
on the order of 30% (see the chart in News for Users in the
April 2016 GeminiFocus). By contrast, in May 2016, we had 16
nights during which we observed nothing at all, and a further
seven during which we observed for less than three hours; in
fact, weather interrupted observations every night to some
degree during this period.
An extended and unusually poor weather period started in
April and lasted well into June, with mainly high clouds as
seen in Figure 1 (but resulting in surprisingly little precipitation). This could be an effect of the strong El Niño event that
is gradually ending. Given that, on average, weather losses on
Cerro Pachón peak in June and July, we can only hope that
2016 isn’t “average,” and that we will have better observing
conditions in the following months. Obviously, the impact
on observations has been significant. Bad weather wiped out
most of the Phoenix visiting instrument run and greatly hin-
July 2016
GeminiFocus
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