Astroblog: The Horns of Venus

Thursday, November 24, 2005

The Horns of Venus

When Galileo turned his telescope to Venus, he saw that it went through phases like the Moon. In that one observation the geocentric solar system was shattered forever (okay, so Tycho tried to save the geocentric system by putting all the planets orbiting the Sun, and the Sun orbiting the earth, but the Ptolemaic system was gone forever). Above are my images of the phases of Venus, you can clearly see the increase an size and crescentness of Venus as time goes on. This is what I love about science generally, is that ordinary people can test out the foundational concepts and observations of science themselves. When I look at the pictures I've taken, I see more than wonky webcam shots, I see a revolution in thinking. I had a big discussion with a member of the ABC Science Matters discussion list about the role of "faith" in science, and the phases of Venus were an example I used of how you don't need to accept statements of Science on "faith", but can check them for yourselves. Admittedly, there are lots of things like particle physics it is hard for an amateur to test, but right now amateurs are imaging transiting exoplanets, so there is a lot you can do.

Speaking of Venus, via davep is this stunning page showing shadows cast by Venus.

# posted by Ian Musgrave @ 7:05 am

Comments:

Real nice image showing change. I trust that you will continue that we can see the sequence of opposing crescents. Without checking, I'm not certain of Venus' visibility for Southerners. When she passes Sun, she becomes the morning star or evening star in Australia.

Are these images shot with any fancy setup or motorized mount?

peter

# posted by

Tag : 11:42 pm

I'll try an keep imaging as much as possible. It really depends on my ability to get up early in the morning (and the early morning cresent phase will be in an unfavorable position from my viewing area). Venus is currently the evening star here, and will become the morning star after January.

No fancy set up. Non- motorized equatorial mount, plain vanilla 4" Newtonian reflector. Imaging system a modified webcam run by Vega.

# posted by

Ian Musgrave : 7:40 am