11 Oct
2006
11 Oct
'06
6:16 p.m.
My understanding is that the black drop effect is atmospheric. Venus has a dense atmosphere, so the effect is pronounced for a transit of Venus. Mercury has very sparse atmosphere, so the refraction by gases does not occur. At least, this is what I've read. I have no solar filters (except for naked eye). But I do have a sunspotter ( http://www.starlab.com/ltiprod.html ), which I will be using to view the event. It's not as fancy as a scope with solar filter; certainly not as fancy as a scope with an alpha filter. But, several people can observe simultaneously. Jim james@cobbzilla.net Chuck Hards wrote: [...] You'll need high power if trying to see the "black drop" effect. [...]