Figure 6.
The May 4, 2018, Big
Island earthquake,
associated with intense
volcanic activity at
Kilauea volcano,
as recorded by the
secondary-mirror sensors
on Gemini North.
Figure 7.
Daily average numbers
of sub-micron-sized
particles at the Nasmyth
platform of Gemini North.
Volcano Watch Activity at
Gemini North
Hawai‘i Island has suffered a long series
of major earthquakes and lava eruptions
in the “East Rift” zone of the Kilauea volca-
no, and a large number of smaller quakes
and ash emissions from the summit crater,
Halema‘uma‘u. While all of this action is a
60-mile drive or more from Maunakea, it
nonetheless has been a concern, as some of
the earthquakes have been major (e.g., the
6.9-magnitude quake on May 4th, the larg-
est since 1975), and volcanic ash reaching
the summit could pose a threat to our opti-
cal systems (chiefly the primary mirror).
So far, Gemini has survived this period quite
well; the large earthquake referred to above
was felt strongly at the summit (and seen
by the secondary-mirror sensors, Figure 6),
but produced no damage to the telescope
or enclosure. As for ash, we have a particle
sensor (installed as part of the Base Facility
Operations project), which gives us infor-
mation on the flux of particles of various siz-
es at the telescope’s elevation
(Figure 7). To date, the only ma-
jor ash event which produced
a significant spike happened
while the telescope was closed
due to high humidity; but we’re
definitely living in strange times
when we have to watch for this
sort of event at night. To com-
plete our monitoring equip-
ment, we are in the process of
procuring a sulphur dioxide
(SO 2 ) detector; there have been
times when observatory staff
on the summit have reported
the distinct smell of sulphur in
the air.
New Data Reduction
Cookbook for
FLAMINGOS-2
A new data reduction cook-
book for FLAMINGOS-2 is now
available. It offers instructions
and PyRAF scripts for the reduc-
tion and calibration of imaging,
as well as long-slit spectroscopy
data in an easy-to-follow for-
mat with a focus on the com-
plete process. A PDF version is
also available by clicking on the
version tab (see the “v: latest”
22
GeminiFocus
July 2018