{"id":585,"date":"2012-06-08T02:35:16","date_gmt":"2012-06-08T02:35:16","guid":{"rendered":"http:\/\/perezmedia.net\/beltofvenus\/2012\/06\/08\/transit_of_venu\/"},"modified":"2023-12-25T04:34:48","modified_gmt":"2023-12-25T04:34:48","slug":"transit_of_venu","status":"publish","type":"post","link":"https:\/\/perezmedia.net\/beltofvenus\/2012\/06\/08\/transit_of_venu\/","title":{"rendered":"Transit of Venus – June 5\/6, 2012"},"content":{"rendered":"
\"Venus<\/a><\/p>\n

H-Alpha view of the Venus Transit – June 5, 2012 – 22:51 UT<\/p>\n<\/div>\n

Wow! Two amazing solar events within a couple weeks of each other–Annular Eclipse and Venus Transit!<\/p>\n

The first bookend Venus transit occurred during the summer of 2004, a couple months before I got my first telescope and actually started getting out to observe amazing events like this. So I missed it that one. Fortunately, the skies were clear over Flagstaff for the second bookend in 2012. We had a perfect back yard view from first contact, until the sun set behind Mt. Elden.<\/p>\n

I had the 8-inch Dob set up with a Baader white light filter, and the PST for H-Alpha. Both views were excellent. I tried to get everything set up a couple hours early so I could test the cameras and start prepping sketches of the white light and H-Alpha features. The sun had loads of detail on display on both the photosphere and chromosphere–a whole mess of sunspots, prominences, and plage\/faculae. So Venus had a wonderfully intricate backdrop to drift through.<\/p>\n

\"Venus<\/a><\/p>\n

White Light view of the Venus Transit – June 5, 2012 – 23:21 UT<\/p>\n<\/div>\n

\"Venus<\/a><\/p>\n

H-Alpha view of the Venus Transit – June 5, 2012 – 23:57 UT<\/p>\n<\/div>\n

With all the back and forth between scopes and eclipse glasses, sketching, photographing, video recording, wiping dust off everything as the wind gusted, I was kind of scattered…which means I’m glad I had three and a half hours to try and get it right. I was working to finish up my H-Alpha solar disc drawing as first contact time approached, so I wasn’t completely keyed in to the exact moment contact. I first noticed the tiny bite of Venus at 3:07 PM (22:07 UT).<\/p>\n

As it slid into the Sun’s disc, I looked for the aureole effect in white light through the Dob, and finally noticed a very faint, very thin hook of dull gray cupping Venus’ dark limb. That became two hooks, and finally a full but tenuous arc–more noticeable close to the limb of the sun, and less defined at the apex of the arc. It was a very subtle effect, and only visible intermittently when the gusting wind paused long enough for the scope to stop bouncing around.<\/p>\n

\"Venus<\/a><\/p>\n

White Light Sequence of the Venus Transit from first to second contact- June 5, 2012, 22:08-22:24 UT<\/p>\n<\/div>\n

As Venus approached second contact, I looked for the black drop illusion, and noted about a 30 second period where the edge of the sun appeared to pull in toward Venus’ disc. This pulled-in region did not appear as solid as Venus–more of a very dark gray instead of black. I’m not sure whether the effect is created by sub-par optics, or if it is a purely visual trick, but it was fascinating to witness.<\/p>\n

As Venus slid across the Sun, I used sunspot alignments to estimate its position at a few intervals. At 4:17 PM MST, as I was observing through the PST, I noticed that some of the plage on the preceding side of AR11498 looked particularly bright and crisp. I had not yet observed a solar flare, but thought this might be one, so I updated that section of the sketch and plotted venus on the solar disc at that point in time to capture my favorite segment of the H-Alpha view. The SolarSoft site shows that a C1.0 class flare was indeed occurring at AR11498<\/a> between 4:06 and 4:26 PM local time (23:06-23:26 UT). Pretty cool!<\/p>\n

\"Venus<\/a>
\n