Posts Made By: Alan French

A nice summary.

http://www.calamitiesofnature.com/archive/?c=571

It's again time to put this to rest and move on.

http://blogs.discovermagazine.com/badastronomy/2011/08/24/case-closed-climategate-was-manufactured/

Clear skies, Alan

Here are the qualifications of the signatories, as listed on the project's web site.

http://www.petitionproject.org/qualifications_of_signers.php

Clear skies, Alan

At http://reentrynews.aero.org/1991063b.html

Clear skies, Alan

If you haven't been out checking out the sunspots (with your safe solar filter), you're missing a great show.

The group is large enough to see by eye alone looking through a shade #14 welders glass (or other solar filter) and is marvelous through a scope.

Clear skies, Alan

This is very interesting. Could comets diving into the Sun trigger CMEs (Coronal Mass Ejections)? We now seem to have two examples of comet impacts followed quickly by CMEs.

http://www.spaceweather.com/archive.php?view=1&day=03&month=10&year=2011

Clear skies, Alan

http://www.bbc.co.uk/news/science-environment-15373071

Spot 1339 is huge, and nicely visible to the unaided eye (through an appropriate filter, of course).

Through even a modest telescope, it is marvelous, and there's a lot more to see too.

Clear skies, Alan

Here you go. Oh, and you also need ATM skills, or deep pockets for a tube and mount.

http://www.astromart.com/classifieds/details.asp?classified_id=754882

Clear skies, Alan

I've been cleaning out my accumulated ATM stuff - the stuff I've gathered over the years with the thought "This might be handy someday." I came across an interesting mystery. It is a 4.25" ~f/4 uncoated mirror about 3/4" thick. When held just right in diffused sunlight (what a photography might call "cloudy bright") it nicely shows colored rings. I've attached a photo.

I'm posting this here because I suspect they are Newton's rings, which I could see in my 5" f/15 refractor objective using a fluorescent light. The rings I see with this mirror are much broader. They do not shift position when I change the tilt of the mirror slightly. The look like they are right on the surface. I can see them through the back faintly, and they still appear as if they are on the front surface.

The back of the blank is flat and very finely ground. My guess is that the blank is free of wedge, and that it is an interference effect between the front and back. An alternative might be some special coating on the front.

The white circle is a sticker on the back of the blank.

Anyone have suggestions or thought on this?

Thanks, and clear skies, Alan