(click here for a version of this page with smaller images)

 

A planetary transit is the observed passage of that planet across the disk of the sun.  In this case, the planet Venus, orbiting the sun “on the inside track,” caught up to and passed the slower earth.   Venus in the foreground moved from left to right across the lower half of the sun.  No one alive today has witnessed a transit of Venus - the last one occurred 6 December 1882.  121 years later, we had another one today.

The sun rose in a clear eastern sky at the TreeHouse this morning (8 June 2004), and the view through the telescope (a Celestron F80 EQ WA with solar filter) was spectacular.  The transit had actually started much earlier (about 1:13 AM Eastern Time), but the sun wasn't visible in North America at that time.  By the time the sun came up here on the East Coast, there was only an hour and a half left of the 6+ hour transit.

Sunrise in our area came at 5:09 AM.  I was up before 5am to set up, and wait.  The sun broke through the tree line just a little before 6am.  I got about a half hour of spectacular viewing and picture taking, but alas, clouds rolled in (around 6:30), well before the 3rd Contact (at 7:05) and 4th Contact (7:25). 

These are some of my better shots using my Canon Digital Rebel SLR attached to a Celestron F80 EQ WA telescope equipped with solar filter. The Celestron is a 400mm focal length refractor telescope, with an 80mm aperture opening and an f/stop rating of 5 (very wide aperture means very good light-gathering properties).

Waiting for the Sunrise Once I had all my equipment set up and ready, there was nothing to do but wait - and shoot some pictures while I was waiting!  That's our Celestron F80 EQ WA scope on a counter-balanced tripod, aimed at where the sun will soon peek out from behind the tree line.  You can't see the solar filter covering the entire far end of the scope...

The Transit of Venus This is my best shot, taken just at 6:00 AM, at 1/30th of a second, f/5, and ISO 100, using the PROGRAM AE setting.  The camera mounted on the telescope shows a true alignment image (not upside-down or reversed).  This was toward the end of the transit, with Venus moving from left to right in the photo.  Difficult to see on this webified image but easier on the original are two faint sunspots, in a snake-bite pattern, slightly below and to the right of center. Click here to view the un-webified version (200kb JPEG file).

This shot was taken one minute later, at 6:01 AM, using 1/10th shutter speed, f/5 aperture and ISO 100, in MANUAL mode.

Yet another view, taken at 6:02 AM, with a still higher exposure. Same settings as the one above except for using 1/5th of a second shutter speed.

This shot was taken at 6:27 AM as the clouds were starting to appear (1/25th shutter speed, f/5 aperture, ISO 100, PROGRAM AE mode).

And finally at 6:28 AM, just before the sun was consumed by the clouds (1/15th shutter speed, f/5 aperture, ISO 100, PROGRAM AE mode).

Cassegrainian Self-Portrait While I was monitoring the transit, I also had my second telescope (a Meade ETX) set up to view the moon, which was in Waning Gibbus. This is a shot looking down into the Maksutov-Cassegrain tube, with my shutter-finger and part of my hair-line reflected in the first mirror.