Zeerust, now-hilariously dated predictions of the future. Or are they? Postulate that something that hasn’t been taken seriously by science fiction in decades in fact comes true in the end.
My entry: scientists discover a nuclear reaction that is the key to unlocking total mass-to-energy conversion. And it uses… radium. That’s right, radium is the super-energy source of the future!
And the radiations from this power source, while relatively harmless to organic matter, are hell on electronics. So you have to do all your calculations at the power plant using slide rules.
The jungles of Venus are under a layer of clouds whose unusual composition had led scientists to overestimate the temperature of the surface by an order of magnitude. The population of Mars id spread very, very thinly, and their agriculture and engineering works are difficult to distinguish from orbit.
The Internet never progresses past message boards, causing earthly inhabitants to idolize troll posters and look to them to solve all worldly problems.