Sunday, November 20, 2011


I've tried to see sunspots by using solar projection with a 68mm refractor, with no luck.  Last night, close to sunset, I pointed my 8" Coulter towards the sun, with a 30mm eyepiece and a card in front of it.  I got a very sharp image with a number of distinct sunspots.  Couldn't see any detail in the spots themselves--they were just dots--but they were there.

Normal solar safety rules apply here: Don't ever look through a telescope or eyepiece pointed in the vicinity of the sun.  (I took care of that by making sure that all the observers were on the side of the scope opposite to the eyepiece.)  Cover up any magnifying finder scope (a red dot finder is fine--just don't use it!).  Don't look at the sun while pointing the telescope (my best method for pointing was to move the scope until the size of the shadow red-dot finder was minimized, and then to wiggle the scope until I saw solar glare on the card).  Don't keep the scope pointed at the sun for too long--give it some cool-off time between observations.

On reflection, I should have stopped down the aperture to prevent eyepiece melting.  I didn't have the eyepiece melt, but maybe that was because it was close to sunset.  I am going to try to make a more comfortable projection setup today.  This is all a sort of preparation for the transit of Venus in June 2012.

My solar viewing was before the Waco star party.  Later that night, we were showing Jupiter to girl scouts, waiting for clearings between clouds.  I think everyone who stuck around got a view.  Some of the time the seeing was horrid, but at one time I did see a fuzzy barge atop the northern belt.  After the girl scouts left, the sky mostly cleared up.

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