GeminiFocus July 2018 | Page 24

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