2 What Every Observer Should Know
2.1 Observing Conditions
2.1.1 Obtaining the best seeing
The telescope may only be used when the observing conditions are favorable (Section 2.1.2). A checklist of the normal START-UP procedure is given in Appendix A.
The best seeing is obtained when the dome air is continuously flushed with the ambient air and sources of heat are minimized. Keep the outer doors to the dome open, and the doors to the control room firmly shut (the latter requires some effort). In order to provide more air circulation you can turn on the fan that is mounted in the east wall of the dome. You are also advised to park the vehicles by the 1.3 m building and to keep the air-conditioning or heating in the 1.3m living area at reasonable levels.
The 1.3m primary mirror is not cooled directly like the 2.4m mirror, so it is important to leave the mirror covers closed until you are ready to observe because the ambient air will be warmer than the mirror.
There is an air-conditioner in the dome that can be used to cool the dome and telescope during the day. It has been noted to improve the seeing. The thermostat has been programmed to turn on in the morning and back off again at night. The observer should never need to touch it unless the temperature is close to the dewpoint. In this case, it would be advisable to turn off the system, thus keeping the dome interior from cooling low enough to produce condensation. The switch for the dome air-conditioner is located on the south wall near the dry-nitrogen tanks.
2.1.2 Limits on Observing Conditions
You should stop observing whenever any ONE of the following conditions are met:
The relative humidity is measured outside the 2.4m dome. It is displayed on the weather station monitor located on the cabinets next to the observing room entrance. A VNC-connection to the 2.4m weather computer can be set up if you ask one of the staff. Use this to determine if conditions are suitable to open the mirror covers. Note that it is always good to check with the 2.4m observer to confirm weather conditions.
The optics are aluminized every two or so years. Please do not spoil the performance of the telescope for everyone by obtaining data under conditions that might risk damage to the mirror surfaces.
A checklist of the normal SHUTDOWN procedure is given in Appendix B.
2.2 Weather Conditions
2.2.1 Weather radio
The National Weather Service forecast for the greater Tucson area can be obtained on the "weather radio", which is kept on top of the cabinets on the south side of the control room. This is updated approximately every 2 hours. A similar forecast from Phoenix is available by switching the frequency knob located under the unit.
A number of links for monitoring the weather on and around Kitt Peak can be found here.
2.2.2 What to do during bad storms
Kitt Peak is very susceptible to bad lightning storms, especially between July and September, and this has caused considerable damage to equipment in the past. If a lightning storm occurs close enough that it appears to be a possible threat:
The lightning shutdown procedure is also posted prominently in the control room. During lightning season make sure that you understand how to carry out the procedure in advance of the occasion for implementing it.
Heavy snow can fall during the winter months. Please make sure that the dome is fully closed. Carefully check the dome for ice before opening the shutters . When lots of ice builds up on the power lines they often break (!) and power at the observatory switches over to an emergency generator.
2.3 Emergency Conditions
2.3.1 Telephone help
To summon help in case of a fire or medical emergency dial 8777, which rings a variety of numbers at Kitt Peak sequentially. If no one answers after a while, dial 8721, which patches to the hand-held radios that are carried by most of the mountain staff. Remember to dial # to disconnect from the radios before hanging up.
2.3.2 Emergency Radio
A Vertex portable radio is available in either telescope control room to call Kitt Peak in case of an emergency. A list of channels can be found on the cork board. Kitt Peak is on Frequencies 1-4; Channel 5 is the National Weather Service; Frequencies 11-15 are MDM channels. Channels 1 and 11 are the standard use channels respectively. Full instructions are given on the control room wall, near the radio. Please read them in advance if you are not familiar with the radio.
2.3.3 Emergency Generator and the UPS
When the commercial power fails an emergency generator automatically switches on. Please note that each dome has its own generator; the 1.3m unit is located southeast of the building, between the garage and the building. If commercial power is lost both generators should be running!
All the critical equipment (computers, instruments, telephones) are kept on an Uninterruptable Power Supply (UPS). The 1.3m telescope TCS and hill are now on their own small UPS system. When power is lost, the equipment on the UPS (orange outlets in the control/computer room/new TCS) is not affected. The emergency generator should start within ~10 seconds.
The generator provides power to the UPS and some additional circuits.
When commercial power is restored it will automatically switch back and the generator will stop. Under normal circumstances you don't need to do anything.
If the generator fails to start, the UPS will run for approximately 1 hour on its bank of batteries. You should check that the generator is running and that the generator power has switched over. To check this, see if the fluorescent lights in the machine shop are working. If not, the UPS is being powered by its batteries and you need to call for support. The Site Manager contact info can be found on the cork board.
Report all problems with the generator (if any) in a Trouble Report.
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