2  What Every Observer Should Know

2.1) Observing

2.1.1) Obtaining the best seeing

2.1.2) Limits on observing conditions

2.2) Weather Conditions

2.2.1) Weather radio

2.2.3) What to do during bad storms

2.3) Emergency Conditions

2.3.1) Telephone help

2.3.2) Emergency radio

2.3.3) Emergency generator and the UPS

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 1.3 m living area at reasonable levels.

The 1.3-m primary mirror is not cooled directly like the 2.4-m 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 switch for the dome air-conditioner is located on the south wall near the dry-nitrogen tanks. During the day the switch should be set to ``cool'' and ``auto''. At night, turn the one switch to ``off'' and leave the other on ``auto''.

2.1.2  Limits on Observing Conditions

You should stop observing whenever any ONE of the following conditions are met:

• the wind speed exceeds 40 m.p.h.
• the relative humidity of the outside air exceeds 85%
• dust is visible in a flashlight beam
• condensation is forming on the railings or cars outside.
• rain is imminent!

The relative humidity is measured outside the 2.4m dome. It is displayed on the weather station monitor located on the control room wall. Use this to determine if conditions are suitable to open the mirror covers. Note that it is always good to check with the 2.4-m observer to confirm weather conditions.

The optics are aluminized every two 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 good, but not always up-to-date, means of monitoring the weather forecast is on the web. The MDM Weather Information web page is a good set of local, mostly reliable links.

These can be read by pressing the appropriate pad on the top line of the unit. Do not touch the bottom row of pads except for SCAN, which automatically cycles through all the readings. Again, note that the 1.3-m weather station is frequently inaccurate; it is always safer to check with the 2.4-m observer to confirm weather conditions.

2.2.3  What to do during bad storms

Kitt Peak is very susceptible to bad lightening storms, especially between July and September, and this has caused considerable damage to equipment in the past. If a lightening storm occurs close enough that it appears to be a possible threat:

FOLLOW THE LIGHTNING SHUTDOWN PROCEDURE AT THE END OF THIS MANUAL.

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.

If the telephones are not working (no lights active) then use the backup cell phone located it the 2.4m lounge.

2.3.2  Emergency Radio

A Motorola portable radio is available in either telescope control room to call Kitt Peak in case of an emergency. Kitt Peak is on Frequency 1. 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 in. Please note that each dome has its own generator; the 1.3-m unit is located southeast of the building, between the garage and the building (photo). 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 1.3-m telescope drive, however, is on commercial power, not the UPS. When power is lost, the equipment on the UPS (orange outlets in the control/computer room) is not affected. The emergency generator should start within 30 seconds.

This generator provides power to the UPS and some additional circuits. The television and other circuits in the lounge are not on the generator supply.

When commercial power is restored it will automatically switch back and the generator will stop. So under normal circumstances you don't need to do anything. But what happens if the generator fails to start?

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 take action.

Figure 2-1 shows the front panel of the generator. Check that the toggle switch is set to REMOTE. If it is not then set it to RUN. The generator should now start; wait 15 seconds and then put the switch back to REMOTE.

If the generator stalls:

1. put the toggle switch to STOP
2. put the toggle switch to RUN
3. wait 30 seconds
4. put the toggle switch to REMOTE

If the unit stalls again the engine may be overloaded: