In a week of portentious astronomical events, we watched the Transit of Venus this morning.
It’s a rate occurence – it won’t happen again for over a century.
It’s also of historical significance because in 1769, James Cook sailed to the South Pacific to observe and measure the Transit of Venus so that scientists could get a better estimate of our distance from the Sun. The idea was that if you could calculate the exact time you observe the transit in one part of the world, and compared the differece with observations another part of the world, you could use that difference and the distance between observation points to work out how far away we were from the Sun.
I was impressed at the quality of the equipment that was available at our kids school. I think it’s wonderful that they are able to get a chance to watch such a special event.
An image of the sun was projected from the eye piece of a telescope onto a screen, and we were able to watch what was going on by looking at the screen – and therefore not putting our eyesight in danger.
I took photos of the screen with my mobile phone. Because I was standing at an angle to the screen, the disc of the sun looked egg-shaped. To fix this, I “stretched” the photos on my computer using a program called “Gimp” to make the sun look round again.
The quality of the image was really good….
If you look closely you can see a few sunspots in the middle of the disc of the sun, and the planet Venus just starting to appear at the “6 o’clock” position at the bottom of the disc.
The next series of photos shows Venus slowly crossing the lower edge of the disc of the sun as the transit begins….
22:33:59 UTC
In the photo above, notice the “Black Drop” effect – the disc of Venus appears to distend towards edge of the solar disc as if it is being stretched.
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