Sonoita Research Observatory
SRO Reaches 500K Milestone
Processing the recent photometric nights at SRO, I realized that we have now calibrated 506,688 stars on at least one night of the 217 photometric nights that I have analyzed. This would not have been possible without the expert attention that John has given the telescope over the past three years. Way to go, John!
None of this would have been possible without the expert researchers using SRO. Thanks guys!
SRO, MPC code G93, located in Sonoita , AZ , is dedicated to research activities. Four astronomers are involved in the activities at SRO. Arne Henden, Director of AAVSO, Cambridge, MA. Dirk Terrell, Senior Research Scientist, Southwest Research Institute, Boulder, CO. Walt Cooney, Director of Blackberry Observatory, Baton Rouge, LA. John Gross, Director of SRO, Tucson, AZ. Current research activities include asteroid lightcurve analysis for the Photometric Survey for Asynchronous Binary Asteroids, photometric calibration of LPV fields, long term monitoring of LPV's, photometric calibration of GRB fields, discovery of LPV's in open clusters, monitoring CV's and novas, and a color survey of W UMa stars.
Observatory equipment includes a 20” F/4 on a Software Bisque Paramount ME, an SBIG STL 6303 ccd camera with CUBVRI filters from Astrodon Photometrics, and a Clement Bellerophon II focuser. The equipment is housed in a Technical Innovations 10' Pro Dome with Digital Dome Works automation. All of this is integrated together for a completely robotic and nearly autonomous operation. The details of the operations are given below.
(1) Observing requests and their scientific constraints (not timing!) are entered into ACP Scheduler by Henden, Terrell, Cooney and Gross days to weeks ahead of time. The requests for a project may require months of observing to complete, yet they may all be entered at once or in pieces for later scheduling.
2) The observations for each night are automatically chosen at the best time (given their constraints) by ACP Scheduler, then fed into ACP Observatory Control Software which manages the overall operation of the observatory instruments to accomplish the observation requests coming from Scheduler. ACP feeds commands
(a) to MaxIm for imager, guider, and filter control,
(b) to TheSky and TPOINT for telescope control,
(c) directly to the TI dome for shutter and azimuth control, and
(d) to FocusMax for autofocusing.
(3) Weather and sky conditions are continuously monitored by the Boltwood Cloud Sensor and the weather server included in ACP which acts as a weather input for ACP. If clouds move in, the change is detected by the Cloud Sensor. ACP Scheduler and ACP will pause observing.
Once the clouds move away, a signal is sent allowing Scheduler and ACP to resume observing automatically. If the weather becomes unsafe, ACP will not only pause but also close the shutter to protect the instrumentation. Later if the weather becomes safe and clear, ACP will reopen, reslave the dome, and resume accepting observing requests from ACP Scheduler.
A typical night's run starts with ACP Scheduler running a script approximately 90 minutes before observing time that opens the dome and cools the camera provided the weather is safe. At the correct time dusk flats in five filters are taken automatically if requested. Then at the appropriate time observing begins when ACP Scheduler schedules the observations and send them to ACP. The telescope is slewed to the target, an autofocus is performed, a pointing image is taken to ensure the object is centered, then the data images are acquired. This continues continuously throughout the night with automatic autofocuses done at 30 minute intervals. And unlike using observing plans in ACP alone, there is virtually no idle time with the telescope all night long. A typical night would gather 180-400 images all taken within constraints set up in ACP Scheduler. In the morning dawn flats are automatically taken if requested and then the dome is closed, the telescope parked and the camera is warmed up. ACP Scheduler then sleeps until the following evening.
The images are automatically mirrored to a Linux server at the observatory each morning. Some images may be reduced and a differential photometry script run on them on site. Regardless of whether this is done all images taken during the night are transferred to an off site high speed server where each investigator can get their images and reduce them in IRAF or Mira. Nearly all of this is done with automated scripts.