A Night At The Telescope

A night at the Mt. Stony Brook Observatory begins not in the dome, but in the warm room. Here the computer that collects the data resides. The computer is set up so that the software for whatever camera is running and the switch box set to channel B. This allows the monitor and keyboard upstairs to operate the computer.

Now the telescope can be set up. The dome is fairly simple to operate. In the North west of the dome, there is a motor that turns the dome. The dome opens with a motor that pulls the slit back. The switch for the slit motor is near the light switches. The slit motor must be plugged in before it is moved. The plug is an eight prong polarized plug that must be unplugged when the slit is open. The power cord is attached to the dome itself. A nice feature to the slit is a horizon shield that can be disconnected from the slit to block the lights from the campus. This also allows the telescope to view at zenith.

The next step is to mount the camera on the telescope. Each camera had a specific alignment with the telescope. This insures that the flat fields are in the same alignment as the images, and that images from night to night do not vary in orientation. The exact alignments are shown in figure 4, but it is important that a consistent alignment was used is.

Once the camera is attached and aligned, the cooler is started. This has been described in an earlier section for each camera. The observer usually has to wait for a fifteen minute period for the Lynxx to cool to temperature. The ST-4 and ST-6 cameras only take about 5 minutes to cool. When starting, the observer should check to make sure that the telescopes are in alignment with each other. Many hours of observing time have been lost by misaligned telescopes. The object of choice is the University Hospital. The lights on the roof provide a nice target to center in all three telescopes.

The first part of data collection is to take the flat fields. Evening twilight flats are usually taken. The campus has a fairly turbulent atmosphere, so morning flats are not superior to these. The dome is placed in the east, and the telescope's drive is turned off. Three images in each filter are taken so that the chip is about 10% saturated. This is done approximately a half hour before sunset.

Once the target has risen, the observer can star hop to the target. This is described in an earlier section. Usually a focus frame is taken of a star to learn if the telescopes are aligned. Once at the target, the observer can go to the warmroom and run the cameras in a warm environment. With the ST-6, the filter wheel is entirely controllable from the warmroom. The Lynxx camera requires manual changing of the filters. The observer can be in contact with another observer via a set of intercoms. The intercoms allow the warmroom to monitor the dome. The ST-6 and ST-4 cameras can control the drive. If there is a malfunction, the person in the warmroom will hear the drive motor slewing the telescope, and he can stop the camera immediately before the telescope crashes into anything.

• The End Of The Night