Transit of Mercury Underway

by Jamie Dillon

Last week I broke down and got a glass solar filter from Orion, for my short tube 90. Brought the scope to school today to show off the transit to my students. The coast was socked in all morning, but by lunchtime it was clear, with some breeze.

This was really fun, and the kids and teachers had a whole range of responses, with a lot of ooh-aahs. I'd been looking at that big spot on the eastern rim for well over an hour, when one of my colleagues took a peek and saw its penumbra. The two smaller spots on the opposite rim, just about 180 across, had penumbras that looked like bright puddles.

It was a gas watching Mercury scoot across the Sun's disk. When it got to the edge, the bite out of the Sun really did look elongated, so the teardrop effect is real after all. This was all thru a Discovery RFT90, f/5.5. Was using a Celestron 17mm Plossl, for the magnification was 29x. Just right for showing the whole Sun in the field, and getting those penumbra. Could also see granulation across the face of the disk, so had a sense of the convection cells.

It was a tweak, and a blow for the scientific empire here in a coastal high school.

Posted on sf-bay-tac Nov 08, 2006 17:03:45 PT
Converted by report.pm 1.4 Dec 12, 2006 21:50:36 PT

Observing Reports	Observing Sites	GSSP 2010, July 10 - 14 Frosty Acres Ranch Adin, CA OMG! Its full of stars. Golden State Star Party	Join Mailing List	Mailing List Archives
Current Observing Intents Click here for more details.