Posted by: SteveInCO | 06 Jun 2012

Venus Transit Pictures

Well, I had decent luck taking pictures of the Venus Transit (I got no usable picture of the annular eclipse–that will teach me to leave the tripod adapter at home).   I tried a movie as well but the movie turned out to just be of a yellow disk, with no visible spot for Venus.

I had to drive west-southwest from Colorado Springs to the town of Salida, then I had to head south from there over Poncha Pass (elevation 9010 feet) and ended up a bit south of mile marker 108 on US-285 in the northern reaches of the San Luis Valley–all to get away from clouds.

The camera was a perfectly ordinary Canon EOS Rebel T3 (not even a T3i).  When I bought it at the big box retailer, they offered a 300mm zoom lens and a bunch of accessories as a bundle (and that bundle was 1/3rd off the aggregate retail).  So I have no doubt the zoom lens isn’t anything special either. I then duct taped an “eclipse viewer” rectangle taped over the lens (yes I literally used duct tape).  It was pretty windy out so I am glad the duct tape held.

17:21, Taken in Salida

You can see Venus in the upper right.  You can also see hints of at least three sunspots, the most prominent almost directly left of the center of the disk.  Another to the right, and a possible pairing down and to the left of the center of the disk.

17:39, Salida… the clouds roll in

In this next picture the clouds are starting to move in.  You can see Venus has moved a tiny bit downwards and to the right.  (This will become more obvious in later pictures.)

18:30, Northern San Luis Valley

Got myself set up in the San Luis Valley for this one.  Fifty one minutes after the previous picture, Venus has moved quite a bit.

One reason I am pretty sure the other spots are actual sunspots rather than smudges on the camera optics or the filter (and I have those too!) is that they always appear in the same place, even though the image of the sun did not (I cropped away over 90 percent of the photo and made sure the sun was centered for this post, but in reality it could have appeared almost anywhere on the original photo.  An optical smudge would not have moved with it.)

19:15, Northern San Luis Valley

19:36, Northern San Luis Valley

Just a few minutes before sunset.  People in the PRK (People’s Republic of Kalifornia) and Hawaii got to enjoy this transit for longer as the sun set later in those locales.

The time stamps should be close to Mountain Daylight time so you folks in more benighted timezones can adjust.

It All Comes Together

You will note the sun traveled down and the tiniest bit to the right across the sun’s disk over the two hours and 15 minutes between the first and last photo.   I will bet though, you had this mental image of the sun traveling from left to right across the sun, rather than from upper left to lower right.  So this doesn’t meet that expectation.  But if you think about it, this makes sense.  I am taking these photos at about 38 degrees north latitude, that means that relative to where I am standing, the sun is tilted something like 52 degrees to the right near sunset, plus or minus how much the ecliptic (which is the plane of Earth’s orbit and Venus’ orbit too) is tilted at the place where the sun is at (which could be anywhere from -23 degrees to +23 degrees–but should be a small positive number at this time of the year).  (Another factor that comes into play is that the tripod was not necessarily perfectly vertical in any shot, and will have changed when I moved from one location to another.)  But if this transit had happened at noon, the direction of travel would have looked more “left to right” rather than “up to mostly down but a little bit to the right.”  An equatorial mount would have compensated for some of this, but I don’t know if they make them for cameras.

So if you mentally “untilt” these photographs it looks like Venus cut across the top of the sun’s disk.  The picture I showed in my post before the transit shows Venus on the sun’s lower left during the 2004 transit.  Again it makes sense; the 2004 transit happened just after what I called the sweet spot, with Venus apparently having gone below the plane of the earth’s orbit.  This transit happened just before the sweet spot, so Venus would be above the plane of the earth’s orbit.  (If it had happened right on the sweet spot, Venus would have crossed precisely through the center of the sun’s disk.)

(By the way this also means the diagram I included that showed the tilt of Venus’ orbit… is backwards.  Venus should be higher than the earth on the left (before the sweet spot) and lower on the right (after the sweet spot).   But the diagram will be correct for the pair of transits happening next century, since it correctly depicts the situation for December conjunctions.)

Anyhow, I thought I’d share the photos quickly, some of you might find them interesting.  I might not be writing too coherently right now, but I need to put this post, and myself, to bed.

Advertisements

Responses

  1. Thanks for posting these!

  2. […] Sun, Transit of Venus, Venus, Venus Transit « Annular Solar Eclipse, 20 May 2012 Venus Transit Pictures […]

  3. […] of orange lights.  Every one of those lights was a burning house.  I did not have my camera (of Venus Transit fame) with me, unfortunately.  (I did have it with me Wednesday but fortunately, I had no need of […]


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Categories

%d bloggers like this: