Report on the meeting of 25 September 2024
If Venus had a moon
We all know that Venus doesn’t have a moon. Don’t we? OAS President Greg Smye-Rumsby listed multiple sightings of a Venusian moon recorded by astronomers since the earliest use of a crude telescope (Francesco Fontana, Giovanni Cassini and many others), and explained how optical illusion and internal reflections were responsible.
Greg explored what we do know about Venus. A “boring” featureless disc to the average amateur astronomer which has with a suffocating corrosive 460℃ atmosphere impenetrable to optical telescopes. In its heyday in the 70s, the USSR had sent missions to the surface which survived just long enough to show a barren mountainous world.
Comparing Venus with the earth (nearly the same size) and Mercury, Greg speculated that its formation (and its “weird” very slow reverse spin) could be the result of suffering impacts from the rain of giant debris falling towards the
sun during the creation of our solar system). At least one of these is thought to be responsible for our moon. So why not Venus?
As always, Greg peppered his talk with a profusion of audience challenges, stunning pictures and fascinating asides. His talk was always entertaining and informed: covering such matters as the (nearly) all-female labels for Venusian
features, and the flattened topology of Mercury.
The kicker? Well it turns out that Venus does have a moon – a tiny sub-kilometric shard of rock discovered in 2002. Named Zoozve, it is a captured asteroid which orbits round the planet in one Venusian year.