The Galactic Archipelago
Should there be extraterrestrial civilizations, some of them could sooner or later colonize the entire Milky Way. But why haven't we heard about them until now? A possible explanation: Settlement is happening in waves - and we are currently experiencing a lull.
On January 15, 1790, nine mutineers from HMS Bounty, 18 Tahitians and a baby arrived on the island of Pitcairn, one of the most isolated habitable places on earth. Surrounded by hundreds of kilometers of open sea, the island in the South Pacific is the epitome of solitude. A group of Polynesians lived on the island until the 15th century, but then died out. So the crew of the Bounty entered a deserted island - and only received a visit from another ship 18 years later.
The story is an extreme example of the unusual dynamics of settlement in the South Pacific. In Polynesia, Micronesia and Melanesia there are tens of thousands of islands scattered over millions of square kilometers. Many of them are just jagged rocks or coral reefs. But there are also paradisiacal islands that have attracted people again and again.
The South Seas shows many parallels to our cosmic environment: There are hundreds of billions of stars in the Milky Way. According to some projections, ten billion of them are orbited by rocky planets whose surface temperatures could be moderate. Like Earth's islands, these exoplanets could provide a home for living beings. And maybe some of them have developed the technology needed for a journey to the stars.
However, this mind game raises a question that the physicist Enrico Fermi is said to have asked as early as 1950…