Friday, 19 October 2007

Venus distance 0.618034 A.U.

Keeping an eye on Venus, and Mars, in the morning sky at present, I checked Stellarium to find out when Venus, and Mars, was at its closest. It seems to have just passed this point, but on Wednesday it was approximately 0.609 AU (Astronomical Units. 1AU being the distance from Earth to the Sun.) At 20.03 GMT, 21.03 BST on Thursday, that is last night, the distance had increased to 0.618(034) AU, the exact phi number. This distance would also have been true a couple of days previous, which I missed. It is perhaps more coincidence than of any significance, but as Venus is a Phi object in relation to the Earth, forming a pentagon every eight years, I note it anyway.

This set planetary patterns is from Bronowskis's The Ascent Of Man, page 190. The caption is:

A sense of the heavens moving round their hub and the hub was the round earth. The diagram shows the paths traced out by the planets as seen from the Earth. The Ptolemaic theory tried to explain these. The photograph shows the movements of Mercury, Venus, Mars, Jupiter and Saturn, (right to left) recorded by long exposure in the Munich Planetarium.

Venus and Mars enlarged.

Emphasizing the importance of astronomy to navigation making the point that the 'New' World did not use the stars for navigation purposes, whereas the 'Old' World did, attributing the seafarers of the Meditteranean in the Greek era with combining adventure with logic, 'the empirical with the rational - into a single mode of inquiry'. He makes the point that although Astronomy is 'not the apex of science or of invention. But it is a test of the cast of temperament and mind that underlies a culture.'

Whether the geometry in the landscape of Britain and the Baltic can ultimately be attributed to Meditteranean seafarers is a debate I don't consider vital for now!

Mars is increasing in luminosity as the Earth swings round towards its nearest point, Mars being in its apparent retrograde loop.

One observation I was not aware of till noticing in Stellarium that a good pointer to north, other than the two stars in Ursa Major, is a line through the gap between Rigel and Bellatrix in Orion through Capella in Auriga. At the oblique angle through the gap in the two Orion stars, it is a more accurate indicator than that of the two UM stars. Once seen Orion is easily identified, and Capella is bright. And if the point at which Orion is at its zenith, nightly in the winter sky at least, a very accurate North south line can be determined.

1 comment:

Anonymous said...

Dear Tom,

I know that this is an old post, but maybe you read this. I'm very interested in that picture of the aparent orbits. I have obtained a copy of The Ascent of Man from Bronowski, but I cannot find that diagram in page 190 or elsewhere. I'd be thankful if you could please tell me which edition of the book you have (if you still have it!), or even make a picture to the whole page.

Thanks a lot.