OBSERVATION #1
Purpose: Observe Jupiter and its moons through a small telescope
Equipment: C8 with white finder scope, on SE pier of observing pad, 25mm ABC and 13mm XYZ eyepieces and a star diagonal.
Procedure:
Setup:
Mounted scope on pier early to allow it to cool to ambient temperature.
Sighted down the barrel of the finder scope to position Jupiter in
the finder.
Used the slow motion controls to centre Jupiter in the finder scope.
Couldn't see Jupiter in the main scope using the 25mm ABC eyepiece.
Had to move the scope around to find it.
Centred main scope on Jupiter. Jupiter was not in finder. Adjusted
the finder scope so that Jupiter was just above (south 1/10 field-of-view)
and to the right (east 2/10 field-of-view) of the finder cross-hairs. (Best
I could do.)
(Note: Sketches can be placed on an adjacent, unlined page in your
log books. Make sure you identify the subject, eyepiece, NSEW orientation
and the size of the field-of-view for each sketch.)
Recentred Jupiter in main scope. Could easily see 3 of its moons - or maybe some are just field stars.
Observations:
9:10pm CDT switched to 13mm XYZ eyepiece.
Could clearly see two bands on Jupiter. Bands were aligned roughly east-west, as were the three moons. FOV of the 13mm ABC eyepiece was too small to see all the moons but the definition of the bands was better in the 13mm eyepiece. Did not see the Great Red Spot on Jupiter.
!!!Meteor or something shot through the eyepiece at 9:22pm CDT.
9:30pm CDT clouds suddenly formed overhead, didn't blow in. Whole sky covered in about 10 minutes.
Closeup: 9:40pm CDT, Temp: +10C, Wind: light west, Cloud: 10/10
No aurora seen this evening. 2 meteors seen, one through the eyepiece!
Conclusions:
Higher magnification showed more detail on the the surface of Jupiter
but was harder to focus the telescope. Image was less steady at higher
mag - jumped around a lot.
Jupiter's moons looked just like stars. Will only be able to tell if
they are really moons by watching them over several nights. (Or by looking
at the positions of the moons in the Observer's Handbook.)***
Figured out which way is north, west in the scope by moving the scope
slightly in each direction and noticing which way Jupiter moved in the
eyepiece. Looking through the C8 without the star-diagonal the directions
are exactly reversed from looking at the sky with your eyes. Star-diagonal
switches one axis (NS or EW) but not the other.
Bill turned on his white light - in my eyes. Couldn't see faint things
in sky for about 15 minutes after that. Red light used for taking notes
doesn't cause a problem.
*** Follow-up on Sept 30 - looked up the
position of the moons in the OH. All three points sketched above were where
the moons should be. Also observed them 2 nights later. The west moon had
moved very close to the planet. See Sept 23 log entry.