Figure 4.
For Gemini South
(upper) and Gemini
North (lower)
the completion
histogram for
Semester 2018B.
Horizontal axis
shows the program
completion in 10%
bins, and vertically
the colored bars
show the fraction
of programs in
Bands 1, 2, and
3, which reached
that completion
percentage.
Main features are
described in the text.
Credit: Andy
Adamson
Gemini North Survives Wild
Weather
Figure 5.
The low-pressure
system to the north
of the Hawaiian
Islands, on February
10, 2019, Hawaiian
Standard Time. The
circulation center is
clearly visible in the
lower-level cloud
pattern (in grey).
Image taken from
the MKWC satellite
archive; go there and
select 11-Feb UTC to
see animations.
As we reported in our recent e-newscast,
on February 10, 2019, a low-pressure sys-
tem (Figure 5) subjected Maunakea to some
of the highest wind speeds ever recorded.
While there’s reason to be skeptical of the
widely-reported peak gust speed of 191
miles per hour (mph), winds in excess of 150
mph (just below Category 5 Hurricane force)
were reliably recorded on the summit on
that day (Figure 6; following page).
Winds of that speed at this elevation, push-
ing on a structure of the scale of the Gem-
ini dome, is sufficient to produce a force of
around 280 tons sideways. The Gemini tele-
April 2019
GeminiFocus
19