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Shopbell, P. L., Kibrick, R. I., Allen, S. L., & Hayes, B. 2003, in ASP Conf. Ser., Vol. 295 Astronomical Data Analysis Software and Systems XII, eds. H. E. Payne, R. I. Jedrzejewski, & R. N.
Hook (San Francisco: ASP), 170
Remote Observing on the Keck Telescopes
Patrick L. Shopbell
California Institute of Technology,
Pasadena, CA 91125
Robert Kibrick, Steve Allen, Brian Hayes
UCO/Lick Observatory,
Santa Cruz, CA 95064
Abstract:
Remote observing has long been a part of the Keck Observatory
operating plan. Remote observing from the Keck Headquarters, in
Waimea, HI, has been operational since 1996, before the second Keck
Telescope came on-line. Remote observing from the Keck HQ now
encompasses over 95% of observing runs at the Keck Observatory.
Recently, additional efforts have been made to enable remote observing
on the Keck Telescopes from the U.S. mainland. Driven primarily by
financial motivations, and enabled by recent increases in the
available bandwidth between the mainland and Hawaii, remote runs from
the mainland are now provided to observers at UC Santa Cruz (UCSC) and
Caltech. Additional locations are in preparation.
In this paper, we present a brief summary of the Keck remote observing
efforts from the U.S. mainland, with an emphasis on the system at
Caltech, which is the most recent to come on-line. We describe the
history and motivation for remote observing with the Keck Telescopes,
outline the remote observing system and hardware, and describe plans
for the future implementation of remote observing on a broader scale.
Remote operation of the Keck Telescopes has always been part of the
long-range plan for the observatory. Remote operations of Keck I from
the Keck headquarters in Waimea began before the Keck II telescope
opened for observations. See Table 1 for a summary of the history of
observing modes at Keck.
Table 1:
Keck Observatory remote observing timeline
1993 |
Keck I science first light |
1995 |
remote control rooms installed at Keck HQ |
1996 |
videoconferencing between summit and HQ |
|
Keck I HQ remote observing first light |
|
Keck II science first light |
1997 |
50% of Keck I operation is remote from HQ |
1998 |
HQ-summit bandwidth upgraded to 45 Mbit/sec |
|
mainland (UCSC) remote observing first light |
1999 |
90% of Keck I/II operation is remote from HQ |
2000 |
HQ remote operation is default mode |
2001 |
mainland (Caltech) remote observing first light |
|
The last few years have seen the emergence of remote observing with
Keck from the U.S. mainland. This effort had been spearheaded by a
group of us from UCO/Lick Observatory. An essentially identical
observing system has been installed at Caltech; it is now operational
and used in a testing mode approximately two nights per
month. Additional remote observing stations, following the same system
parameters, are being established at other sites, including UC San
Diego and UC Berkeley.
When the Keck Telescopes began to be used remotely from the Keck HQ in
Waimea, HI, the motivations were twofold: First, to increase service
for the observers by providing a direct link between HQ observatory
staff and the observers at the telescope. Second, remote observing at
Keck HQ provides a much less demanding observing environment, due to
its altitude of a mere 2,500 feet above sea level. In extreme cases,
Keck HQ provides a safe alternative to those unable to ascend the
mountain (e.g., those with heart conditions). In the average case, Keck
HQ simply provides a much more comfortable environment, with 60% more
oxygen than the summit of Mauna Kea.
In recent years, additional factors have arisen which have motivated
remote observing from the U.S. mainland, even from the home
institutions of the observers. The primary impetus here has been
financial: Some hundreds of thousands of dollars are spent each year
on observing travel alone. In more than half of cases, these costs are
for runs of one night or less. The cost is increased if one includes lost
time for travel (usually 2 days). Finally, remote observing from the
mainland provides a way for increased involvement by large groups,
students, and collaborators.
The remote observing system has been designed for a high level of
redundancy, to ensure minimal loss of observing time in case of
failure. It is functionally equivalent to the systems at the Keck
HQ and the Keck summit control rooms:
Sun Ultra 10 instrument computer with 3 LCD monitors |
Sun Ultra 10 backup instrument computer with 1 LCD monitor |
Redundant graphics and SCSI cards |
Exabyte Eliant 820 tape drive for data backup |
Polycom 512MP videoconferencing station |
Cisco 2600 router with 4-port ISDN card |
The videoconferencing unit is a critical component of the remote
observing system. Remote operations typically involve three sites:
observers at the remote mainland location, observers at Keck HQ, and
the telescope operators on the summit of Mauna Kea. The
videoconferencing system provides a crucial link between these
parties, allowing for much better communication than a simple voice
line. When problems arise, the videoconferencing system can be used to
share paper documents, audible noises, and computer output screens
(thus the use of LCD panel displays on the computers).
Figure 1:
Schematic representation of the Keck remote observing
network. The asterisks denote the four remote observing stations
currently operational or under development. The dotted line denotes
the backup network link via a group of ISDN lines.
![\begin{figure}
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\end{center}\end{figure}](img3.gif) |
To ensure complete redundancy of the remote observing system, a Cisco
2600 router with a 4-port ISDN card has been installed. During normal
operation, the router is configured to pass all traffic over the
standard Internet. (As of the year 2000, the Internet-2 project has
enabled a peak bandwidth of approximately 35 Mbit/sec between the
mainland and the summit of Mauna Kea.) If the router senses at any
time that the Internet connection to Keck has failed, this route is
disabled and a set of ISDN lines to the summit are activated. Although
the ISDN lines provide much lower bandwidth (128 Kbit/sec per line),
it is sufficient to ensure that critical traffic is passed. In
particular, the observing software contains a number of timeouts that
are triggered after inactivity for
seconds. Given that
network traffic between the mainland and Mauna Kea must traverse some
dozen different networks, approximately one third of the remote runs
from Caltech (thus far) experience a network dropout. These dropouts
typically last 2-3 minutes, but are easily handled by the ISDN
failover system.
Remote observing with the Keck Telescopes is expected to slowly
expand, to encompass additional remote sites and more flexible
observing modes:
- Reliable remote observing with the Keck Telescopes is now
possible from the U.S. mainland. Observing sites include UCSC and
Caltech, with UCSD and UC Berkeley coming soon. Current redundancy
requirements effectively prohibit remote observing from arbitrary home
institutions, and there are no plans in this direction.
- Observatory policy currently requires at least one observer to
be on-site at Keck HQ, to ensure that telescope time is not lost in
case of remote system failure. As reliability is increased and
experience gained, this restriction may be relaxed.
- Hardware for remote observing is easily affordable, especially
when the cost savings are included (i.e., from travel). The available
network resources are currently sufficient for observing with
first-generation instruments on Keck. It remains to be seen how well
advances in networking will keep pace with the next generation of
larger detectors and more complicated instruments.
- The social implications of remote observing are complex and
not yet fully understood. On the negative side, one must appreciate
the impact of further distancing the observer from the telescope and
observatory staff. On the positive side, the possibilities for group
collaboration and education are clearly vast. Understanding the
importance of such issues may be the key to a successful remote
observing system.
© Copyright 2003 Astronomical Society of the Pacific, 390 Ashton Avenue, San Francisco, California 94112, USA
Next: Chandra Monitoring, Trending, and Response
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Previous: COSMOS-3: The Third Generation Telescope Control Software System of Nobeyama Radio Observatory
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