Several Low-Earth-Orbit (LEO) networks were proposed, but only one got off the ground: the Iridium system. The original Iridium proposal called for a "constellation" of 77 satellites, which gave the plan its name: the element iridium has atomic number 77, meaning that an iridium atom has 77 orbiting electrons. Before the satellites were launched, the constellation was scaled back to 66 active satellites, but no one wanted to change the name to Dysprosium.
A NASA astronaut, forced to retire years earlier so he could save his family farm, has never given up his dream of space travel and looks to build his own rocket, despite the government's threats to stop him.
We might be closer than we think to cures for depression, hypertension, and yes, even obesity.
The answer to scurvy was just one thing, plus a few wrinkles — mostly “not all citrus has the antiscorbutic property” and “most animals can’t get scurvy”. This was only difficult because people weren’t prepared to deal with basic wrinkles, but we can do better by learning from their mistakes.
This means don’t give up easily. It suggests that there is lots of low-hanging fruit, because even simple explanations are easily missed.
Lots of theories have been tried, and lots of them have been given up because of something that looks like contradictory evidence. But the evidence might not actually be a contradiction — the real explanation might just be slightly more complicated than people realized. Go back and revisit scientific near-misses, maybe there’s a wrinkle they didn’t know how to iron out.