This reality has space travel thanks to luminiferous aether actually existing allowing the existence of reactionless drives.
- Vulcan exists but no one has tried to land on it
- Mercury is mined for its mineral wealth
- Venus is a tropical planet where intelligent beings from the poles are turned into indentured servants or slaves.
- Mars is dotted with ruins that are of interest only to archeologists.
GURPS Steampunk was published in 2000 so in theory Etheria should be further along (around 1895) in our 2006.