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A Magellan mission radar composite of the surface color coded to show elevation.

Venus is the third brightest object in our sky and it has been quite evident in our western skies for over a month now. It's apparent distance from the Sun will continue to grow in the coming months so that it will dominate the evening well after twilight. Aunt Claire and I observed it and Mercury at midday during a ring eclipse of the Sun in 1994. Experts can spot Venus in binoculars in spite of a bright Sun. Venus and Mercury are referred to as the inner planets. They orbit closer to the Sun than we do. Venus is the hottest planet in the solar system even though Mercury is nearer the Sun. This is due to the thick, heat-trapping atmosphere of sulfuric acid, a belt that fills a space between 28 and 43 miles above the surface. The heavy atmosphere also creates a surface pressure 90 times greater than Earth's. Venus follows the pattern of having a shorter year than its outer planets at 225 Earth days, but it also has its quirks. It rotates slowly and it rotates in the reverse direction vis a vis Earth. Its day lasts for 243 Earth days, making its year shorter than its day. The Sun rises in the west and sets in the east but it's doubtful an observation made from the surface could actually pinpoint the Sun's location. What do you think? Venus, having an inferior orbit closer to the Sun, occasionally passes in front of the Sun's disk from our perspective. These occasions are rare due to slightly different tilts of the two orbits. If you missed the two recent transits as they are called, in 2004 and 2012, you'll have another chance to observe them in the years 2117 and 2125, that is, if you live past your 100th year, and who knows, we won't sell medical science short on that one. More info and a jumping off point for even more is at NASA

Listen to The Planets by Gustav Holst. What a contrast!



September 2021