Infrastructure at SRO
There are several critical elements to sound infrastructure. Our site has excellent intrinsic characteristics, such as sky darkness, transparency and seeing. We have unusually easy access for a site with these characteristics. There are few thunderstorms, no summer monsoons and almost no wind. However, without a sound infrastructure, these characteristics of little consequence. There are several characteristics of any observatories infrastructure which includes the structural characteristics of the observatories, technical support, internet service (including internet security and backup), local networking, weather/sky telemetry and roof control. We’ll discuss these as follows.
There are 8 individual roll-off roof observatories and larger multi-telescope buildings which each house 12-14 telescopes. Telescope sizes range from small refractors to 28” RC telescopes. The floors are intentionally wooden to decrease the slow nighttime release of heat seen with concrete floors. All the multi-telescope buildings have 9-10 foot ceilings to make it impossible for the telescopes to contact the roof, regardless of the position of the telescope, so that the roof can open or close at any time without damage occurring. The roll-off roof model is typically used at SRO because we have little or no wind and the thermal equilibrium is very fast for these structures.
At SRO technical support is available for onsite upgrades, repair and maintenance. Currently we have Evan Cornelson, who has a strong computer science background. We are also seeking a second technician, in order to have redundancy and increased breadth with regards to technical support. The owners are also frequently on site as well. Most issues can be solved without shipping equipment out. Machine shop services are provided by SRO and by local businesses such as Ross Engineering. Because we are relatively close to a major metropolitan area, we have access to local experts. Of note, PlaneWave Instruments is only a few hours away by car.
When SRO was first founded in 2007 we initially had T-1 internet service. As the number of clients exponentially increased, we became aware that this might eventually prove to be inadequate. Fortunately, 3 years ago our Internet Service Provider upgraded us to fiber optic internet and additionally eased their internet throttling which brings our available bandwidth to even higher rates than would normally be possible. Currently we have speeds of 100 Mbits/sec for uploads and downloads with full duplex. We have over a dozen fiber optic cables available should our bandwidth be exceeded. We also have the option of increasing our internet speeds up to 2.5 Gbps.
We have automatic satellite internet backup with Broad Sky, in the unlikely event of the fiber optic internet crashing. This has not happened and is unlikely to do so. Nonetheless, we have endeavored to make all our critical systems at SRO redundant or backed up, so that our clients will not lose contact with their telescopes in the event of a major communications problem.
We have taken measures to make our site safe and secure. Those changes remain proprietary and we do not share information regarding our security systems for obvious security reasons. In addition, there is private and secure VPN for each client.
Weather and Telemetry
Currently we have two AAG CloudWatcher units, professional grade IR cloud and humidity/rain sensors (with computer bypass). The bypass will send a signal to the roof to close with a rain event, even if the site software fails. This is another example of redundancy of systems at SRO. There is a Mark-III RainWise weather station, a commercial grade weather station with temperature, wind speed, rain and humidity sensors.
For sky quality we have a Unihedron/Knightware sky quality meter for measuring site darkness. Sky transparency is also measured.
There are two seeing monitors, an SBIG seeing monitor and Alcor Systems Cyclope seeing monitor. The Cyclope seeing monitor is a professional grade seeing monitor from Alcor Systems, which is being used at a number of professional observatories. It is a robust and sealed system with built in temperature and humidity detectors which allow it to clear any dew form it’s window. It is reliable and accurate. You can learn more about the unit at Alcor’s website. Mel has spearheaded our acquisition of the Cyclope and is testing the device. The data we are getting from Clyclope is similar to our older SBIG seeing monitor but far more accurate.
Web cameras with passive ultra sensitive night vision are posted throughout the observatory.
There is a EUDA All Sky Camera, a professional grade All Sky camera from Alcor Systems. This camera has an 8 MP cooled chip camera equipped with a filter wheel which is especially useful for cloud detection. You can see the Alcor cameras in use at Kitt Peak and other professional observatories by going to http://www.astrosurf.com/cavadore/meteo/current/allSkys.html .
Weather Station Update: Over the years we have always had difficulty integrating precision humidity measurements with cloud and rain detection in a reliable and repeatable manner. To remedy this, in 2015 we installed a RainwiseMK-III-LR weather station along with an AAG cloud and rain detector. This hardware is now integrated using AAG WeatherCenter software which allows a single “Boltwood” file to be assembled even though the data comes from separate sources. Now, when the roof closes because of high humidity, you can go to the new weather section of the SRO web site and find out what happened. This same data is used with our custom roof automation software. If you are interested in historical data, you can see the RainWise data at the following sites: http://www.rainwise.net/weather/sro and http://www.wunderground.com/q/zmw:93602.1.99999?sp=KCAAUBER13
All telemetry data is available on SRO website at www.sierra-remote.com.
SRO uses an intelligent roof management system based on the commercially distributed ‘m1OASYS’ roll-off roof controller coupled with a custom developed roof management application that monitors weather utilizing a number of weather telemetry capture devices. Current weather conditions are then evaluated once every few seconds for any kind of actionable changes in conditions, such as cloud cover, humidity, dew levels, and/or precipitation. Should an actionable weather change be detected, the roof will then be closed to protect our clients’ equipment from any kind of adverse conditions. Once good observing conditions have been re-established, the roof will then re-open to provide optimal client access to productive observing time. This year we have improved the roof control application both by rewriting its logic used to talk directly to the M1 Oasys system and by installing direct precipitation detection into the M1 itself. We consider the direct precipitation detection particularly important since precipitation roof closure is no longer computer dependent and will activate even with full network failure.
Other Infrastructure Updates
We now have added hardware to our local network that offers both Network Time Protocol (NTP) and Precision Time Protocol (PTP). Geoff Stone, who performs photometry, has made these updates. This has been helpful for those engaged in precision astrophotography, such as those involved with occultation studies and satellite tracking.
Documentation: Although not strictly a “physical” update, we have written informational packages on how to get set-up and running at SRO, largely put together by Larry and Geoff. These documents have made startup at SRO much less complicated.
We hope this review will give you a sense of our attention to the details of a seamless and efficient infrastructure. Environmentally, there is no question that SRO is unique and well suited for remote astronomical imaging and data acquisition. However, without a sound and robust infrastructure the site would be essentially useless. For this reason we are continually upgrading the infrastructure of SRO.
The Lost Valley Observatory
Located at Sierra Remote Observatories
Keith B Quattrocchi