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This is page is intended for sections taught by DavidJ.
Other sections should prepare as their instructors require.
If you have to miss the lab final night for any reason, don't worry. Makeup lab finals can be arranged.
Some adjustments/corrections may be needed before the lab final.
Note for the instructor: Search on UPDATE for items which usually require updating for each semester's lab final.
Sections
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A planisphere and its use are illustrated in the figure below.
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What you will do with the planisphere:
You will be asked to explain the function of . The instructor chooses which parts you will have to explain.
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The instructions above are for the newer LCD keypads
for C8 telescopes.
The instructions for the older LCD keypads---which are probably all gone now---are
almost the same---in fact, virtually the same,
mutatis mutandis.
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If the instructor has an assistant, the students can be sent up as they are ready and the assistant will give them the outside part using 1 or more C8's.
Caption: A 1673 woodcut of a 8-inch objective (i.e., primary lens), 45-meter-long aeriel telescope constructed by Johannes Hevelius (1611-1687).
In the 17th century (which was before the achromatic lens and before the significant development of reflector telescope) chromatic aberration (the failure of simple lenses to focus all wavelengths of light in the same place) was a problem for observing. Objects of more than one color (which is most objects) were blurred.
Using a very long focal length objective greatly reduced chromatic aberration.
So very long refractor telescopes were built.
The telescope tube was eventually dispensed with since the tube is actually not required for the essential functions of the telescope. The tube provides scaffolding for the optical elements and can protect the optical elements from dust and other harms, but it serves no optical function usually. Large modern reflector telescopes generally have no tubes.
The idea for the aeriel refractor telescope is credited to Christiaan Huygens (1629--1695) and his brother Constantijn Huygens, Jr. (1628--1697) circa 1675, though others may have had the idea earlier and/or independently.
Hevelius's aeriel telescope is from earlier than 1675. Yours truly cannot say why the brothers Huygens are given primacy.
Credit/Permission: Johannes Hevelius (1611-1687) in Machina coelestis, part 1, 1673 (uploaded to by User:Marshallsumter, 2011) / Public domain.
Image linked to Wikipedia.
Do NOT be late.
If you arrive before 7:30 and/or your scheduled time, you can usually do some last-minute practice.
Sometimes, we run ahead of schedule, and so some students can finish up early sometimes.
In case the weather is not good for observing, you need to have an alternate indoor test ready. Yours truly suggests ????---well we will cross that bridge when we come to it.