by Matt Tarlach
From: Brent Hutto
The dome described by Dave North on the Rukl Chart 13 entry in the Hitchhiker's Guide is beautifully lighted tonight. At 9:30PM on the US East Coast.....
I wish I'd read your post before going out myself! I was looking mostly South and West of the area, but did scan about and failed to notice the dome.
Looking at the Rukl chart, it appears huge! I was looking about 3 hours later than you, here in CA....perhaps the light changed enough in that time to make it less apparent.
Star of my session was the Hyginus rille. It was lit just about perfectly, as I observed from around 0330 to 0530 UT on June 9. At 182x in my 80mm f11 Vixen achromat, the eastern length of the rille appeared uneven and interrupted. For some reason it reminded me of a line of Morse code. I could not resolve the individual craters within the chain, but in moments of fine seeing could see the break that Rukl plots at about 7.5* E. There were also several splashes of light material to either side of the rille. When I went out again at about 0700 UT, the crater Hyginus was apparent as a rimless black pit, and the western portion of the rille was clearly seen as a chain of small, black, rimless craters overlapping one another. This was my best view of Hyginus yet!
Other interesting features noted were the Boscovich rille, the Sulpicius Gallus rille, and a large splash of very bright material around Sulpicius Gallus A.
No sign of aurora, but limiting mag from my yard is only 4.5.