The nerve center of the telescope system is the Control Computer, which sits inside the climate-controlled computer Enclosure with the monitor, keyboard, mouse, and UPS. The computer runs Windows XP and all the Telescope control software, and remains powered on continuously. The computer collects weather information from the SALT and SuperWASP weather stations every 5 minutes of the day. At about 30 minutes after sunset the computer checks the weather conditions and opens the roof. A series of flat field images are then taken of the twilight sky. The computer then instructs the roof to close and a series of dark and bias images are taken with the telescope pointed at the floor in "standby" mode.
At 20 minutes before 18 degrees twilight, the computer checks the weather feed again to decide if observing operations should take place. If the weather is still clear, the computer tells the roof motor to open the roof, and tells the Camera to start taking images on the east side of the meridian only until 18 degrees twilight.
At 18 degrees twilight, the computer directs the telescope to observe the all fields for the night, and subsequently tiles between all the observable fields on both sides of the meridian. Between each exposure, the computer checks the weather feed to be sure the weather is good, checks the computer clock to determine the next field to observe, and checks the roof limit switch to ensure that the roof is open. If any problems occur, the computer closes the roof and shuts down the telescope. All computer operations are saved to a log.
At 18 degrees dawn the computer instructs the telescope to observe fields on the east side of the meridian only for another 20 minutes. After this is complete, the computer closes the roof and instructs the telescope to take another series of dark and bias images with the telescope in the "standby" position.
At the end of the observing run all images are analysed to determine whether they should be kept or deleted due to cloud contamination. The files are then compressed and the computer copies all data from the night to the two external hard drives. It then emails the log file and 3 sample images from the night’s observations to the server in Nashville as bandwidth permits. When the hard drives are close to filling up, a technician at Sutherland will replace the drives with empty ones, set aside on drive for storage and mail the other to Nashville. Once the shipped drive arrives in Nashville and the data is copied over and checked, the drive in storage is placed back into rotation for future use.
Red lines mark power connections, Blue lines mark data connections.
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