Tag: Sun

Transit of Venus

I’m taking a break from work here at the Palo Alto church, and watching the transit of Venus. I’m projecting an image of the sun using a pair of 7×25 binoculars mounted to a tripod. I have a white card set up about six feet from the binoculars, resulting in an image that’s approximately five and three quarters of an inch in diameter. The optics in the binoculars are not particularly good, and there’s enough chromatic aberration that I don’t get a particularly crisp image. Nevertheless, I can clearly see the shadow Venus is casting as it crosses the sun; on this projection, it’s approximately three-sixteenths of an inch in diameter, and at this time about one and three sixteenths inches from the nearest edge of the sun. The card I’m projecting the image on is eight and a half by eleven inches oriented horizontally; the earth moves such that I have to readjust the binoculars every sixty or seventy seconds in order to keep a complete image on the card.

Venus does not appear to be moving in relation to the sun. I suppose if I sat out here long enough, I’d be able to see some relative motion; but the transit is going to take four hours, and I don’t suppose I can take that much time away from work.

And yes, the transit is a pretty amazing phenomenon to watch, even with my crude projection device.

Corrected per Erp’s comment.

To make you feel humble

NASA is celebrating the one year anniversary of its Solar Dynamics Observatory, and they’ve been featuring this photo on their Web site: a photo of a March 30, 2010, solar eruptive prominence, taken in the extreme ultraviolet range. NASA has superimposed a photo of the Earth to provide a sense of scale.

Dang, we are tiny:

This reminds me of the extended monologue by Yhwh in the book of Job (ch. 38 ff.). Though framed in the cultural referents of the Ancient Near East, Yhwh’s monologue has the same effect on me as does this photo — both make me realize that we humans are insignificant when considered in terms of the vastness of the universe. Our essential insignificance seems to bother some people, but to be honest I find it comforting — I’m often not very impressed with humans, and it’s good to know that there is something out there which is much bigger and grander, and more permanent, than we are.