This write-up is intended for use by students who have taken the Telescope Training Class and are on the access list. It is not a sufficient substitute for the class. If anyone finds an error or omission or has suggestions about revisions, please leave a note in the logbook at the observatory or e-mail stahrgazers@gmail.com. STAHR officers will edit the write-up accordingly.
Most of the material here is just descriptions of routine procedures; however, in a few cases there are CAPITALIZED WORDS which refer to the few but extremely important rules of safety. If you plan on using the equipment in the observatory, DO NOT IGNORE these – they have been worked out after over 40 years of experience with the observatory’s instrumentation, and if you disregard them, you may wind up with broken equipment or an injury.
Names of officers and contact information are routinely posted on the blackboard. If you have general questions feel free to call us during normal hours. If an emergency occurs, do not hesitate to call us, whatever the time.
1. Getting up to the telescope
Once you have successfully passed the Telescope Training Class and gotten a 100% on the Telescope Access Quiz, your HUID number will be added to the observatory access list.
2. Opening up
Before going to the observatory, make sure to reserve it in Roombook! We’ve prepared a document explaining how to do so on your mobile device; the process is similar on a computer, and it’s fairly intuitive. Please contact us with any questions!
A. Logging-In and the Logbook
When you arrive, first log into the logbook on the desk. Put the date, your name, and the time you begin. Take a quick look at the last entry before you and make certain that nothing is broken or damaged that you need to look out for. This can be especially important if there has been any electrical failure. When you leave, log the time, what you did, anything interesting that you saw (or that saw you) and ANY PROBLEMS you had. This is especially important if it needs fixing, so we know exactly what happened and can fix it early.
If you have problems while you are observing that really need an answer, i.e. you are stuck, call one of the names on the blackboard. If it is after midnight, though, call only if you have a problem such that you cannot leave until it is solved (e.g. roof won’t close, telescope is on fire). Otherwise, if you have general problems or questions, log them in the logbook and email stahrgazers@gmail.com, and a board member will respond to your email.
B. Weather at the Observatory
Now you are ready to open the dome, PROVIDED IT IS NOT A) RAINING, B) SNOWING, OR C) TOO WINDY. If the wind is gusting 25 m.p.h. or over do not open up the dome. Unpleasant things can happen to the shutter in high winds. It usually is wrenched off its tracks and you will not be able to close it again. Also, do not open the dome if there is freshly fallen snow on the dome.
C. Shutter and Lights
Wait to take the lens cap off of the telescope until the shutter is fully open. This is a new rule (as of spring 2022) designed to prevent further water damage to the telescope.
To open the shutter (the big long slot in the dome), plug the cable which runs from the top of the dome into the outlet located to the east of the door. Make sure to turn off the white lights before opening the shutter. People in the astrophysics department often use the Clay Telescope (located on the roof), and any bright light will overexpose their observations. Switch on the red lights by turning the knob (next to the door where you entered) clockwise. Now to open the shutter, push the red knob (on the top of the gray box, above where you plugged the shutter cord in) to the right. The shutter will begin to open. Do not worry if it makes loud thumps, groans, creaks, sighs, and wailings on the way up – it always does.
One of the most important rules of the telescope is NEVER CLIMB OUT ON THE ROOF THROUGH THE SHUTTER OPENING. There are two reasons for this; one is that you may fall off the roof, and the second is that occasionally the detachable part of the shutter decides to detach itself, and it then comes sliding down the tracks and crashes down at the bottom, and you will not have time to get out of the way. The shutter weighs around a ton, and will definitely kill you. Do not risk it.
3. Rotating the dome
Once you have successfully opened the shutter, turn the red knob back to the center position. Now unplug the overhead cable. To rotate the dome, plug the cord in the wall (labeled “rotate”) into the same plug as you used to open the shutter. If you turn the red knob to the right, the roof will rotate clockwise; to the left, counterclockwise. Again, do not worry about thumps and wailings.
4. The Telescope
The observatory houses a large, 10 inch refractor which can be used for observations through the opened dome. There are also other more compact telescopes kept and maintained by STAHR at the observatory that can also be used. These telescopes can be taken out on the observation deck, if you’d like, but please be sure to return them to their place inside the dome once you’re done with them. If you’re interested in using the smaller telescopes, reach out to harvardstahr@gmail.com.
A. Telescope Parts
The telescope consists of the main tube, the ‘finder scope’ (located beside the eyepiece), and the Ross camera (the short, fat tube clamped on half-way up). The motor is housed in the pier. Please DO NOT open up the doors to the pier, let alone put your hands in. It is not insulated and uses enough power to knock you down.
B. Motor and Lights
Turn on the motor (the right switch on the north side of the base of the telescope). You will want to leave the motor on all the time you are observing, because it powers both the tracking mechanism and the control paddle. However, ALWAYS TURN THE MOTOR OFF BEFORE YOU LEAVE. As of spring 2022, the left switch (labeled “lights”) does not do anything; no need to turn it on.
C. Moving the Telescope
In order to move the telescope, you can manually push it in whatever direction you desire. The most important rule when moving the telescope is to NEVER MOVE THE TELESCOPE USING THE FINDERSCOPE. The finderscope is aligned with the main telescope, but if you put too much weight on it by pushing, it can unalign.
Another very important rule comes up here; NEVER LET THE TELESCOPE GET MOVING TOO QUICKLY. It is beautifully balanced, and moves very smoothly, but this is deceptive; it weighs a couple of tons, and with that much mass can get up a lot of momentum. If it gets going really fast, you may not be able to stop it before it crashes into something, and the impact may break all sorts of things, like the objective lens. So the rule is that if you are moving it any real distance, hang onto both ropes, one in each hand, move it slowly, and WATCH IT.
If, while trying to move the telescope, you find that it suddenly does not want to move, DO NOT FORCE IT. Check the cable running from the telescope to the mount, up beside the RA circle. If the telescope has been rotated too many times around one way, this cable will be wrapped as tight as it can go, and if you force the telescope, one of the wires inside the cable may break. Also, keep an eye on the two ropes, the overhead roof cable, and the paddle clamp box cable. They tend to get tangled around the telescope as well.
D. Lens Caps
Once the dome is open and everything else is prepared, Climb up either on the pier or the bleachers and move the telescope toward you until you can reach the top of the finder scope and take the lens cap off. Finally, pull down the other end of the telescope and take off the primary lens cap. Once you’re done observing, make sure to put the lens caps you removed back on.
8. Eyepieces
We have a number of eyepieces in the wooden box in the second drawer from to top of the filing cabinet. The eyepieces are, in focal length, 28mm, 18mm, 12.5mm, 9mm, and 6mm. The standard to use is the 28mm since it has the widest field of view and makes it easier to locate things. Once you have found something, you may want to try the 18mm or 12.5mm. These are higher magnification and may produce clearer detail. The 9mm and 6mm are usually only useful on very clear and steady nights, because if the seeing is jumpy they are hard to focus. Experiment!
To put in an eyepiece, loosen the twist-clamp on the side of the eyepiece holder one or two turns – never let it get really loose or the whole gismo will fall apart, and it is a trick to re-assemble. (If this happens, log it and leave it to us). Slide the eyepiece in and tighten the clamp until you are sure the eyepiece is securely in.
Please do not attempt to clean or disassemble the eyepieces. Anything except special lens paper will scratch them, even the softest cloth. Also, if you take them apart all the little lenses will fall out and get lost. If an eyepiece is really dirty, log the fact and we will clean it. Also be careful when carrying the eyepieces about – do not let them bump together in your pocket. Try to have only one out of the box at a time. It is also best to leave the box in the drawer. If you put it on the pier or bleachers, it might fall or get stepped on.
9. Clean-up
We have posted a check-list on the dome door of all the tasks you need to do before leaving the dome. Essentially, do your start-up procedure exactly in reverse. MAKE SURE THAT YOU’VE DONE EVERYTHING ON THE CHECKLIST BEFORE YOU LEAVE! Also, please make sure to have the key in your hand!
Enjoy using the telescope!
Clear skies,
STAHR Board