network connection to the summit is lost. In
addition, without any staff available to press
buttons when something minor needs resetting, BFO also needed the provision for remote reset capabilities.
Figure 2.
TBAD receiver on the top
ring of the Gemini North
telescope in Hawai‘i.
A complex software sequence for dome closing was also developed at the lowest level
(Programmable Logic Controllers). This new
feature avoids relying on computers to perform one of the most critical tasks identified
when we defined our telescope and instruments safety requirements — the autonomous closing of shutters and vent gates.
The electronics that control the primary mirror covers and their mechanisms were also
upgraded to make their operation not only
safer for the primary mirror but also more reliable. This improvement allows us to open
and close the covers remotely from the base
facility as well.
For instance, Gemini North can now remotely
turn systems on and off that could previously only be controlled at the telescope facility.
Also, Gemini has long used human spotters
to detect aircraft and alarm telescope operators of possible accidental illumination from
the Gemini laser. This system became unworkable under the new operational model,
so we reached out to our colleagues at the
W.M. Keck Observatory and joined in a very
successful collaboration that resulted in an
automated Transponder-Based Aircraft Detector (TBAD). Developed by Keck and Tom
Murphy at the University of California, TBAD
can monitor aircraft transponder signals, determine whether the craft are too close to
the area of laser propagation, and, if so, send
a command to close the laser shutter without any human intervention.
Our Gemini North generator power transfer
system also needed attention, so we modified and improved it to remotely, and autonomously, close the dome if a power outage
occurs. The system will also work even if the
January 2016
To make the work environment more suitable for nighttime operations at the base
facility, we’ve modified the control room so
it can accommodate additional monitors
and network connection ports, provide better lighting, and support additional security.
Finally, the telescope facility had to be upgraded to improve its dialup notifications
infrastructure and security system, as well.
The Trial Run in Hawai‘i
During BFO’s trial operations phase at Gemini North, we completed internal testing of
most of the critical work packages and followed that with user testing and verification.
For the first time, on the night of September
8-9, 2015, a full test of the remote observing
capabilities at Gemini North was successfully completed operating in “base mode” while
the night crew was still at the telescope. Over
the two following weeks, the night crew (Science Operations Specialists, SOSs) refrained
from going outside the control room to see
2015 Year in Review
GeminiFocus
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