Interstellaire planeten.

Was a Giant Planet Ejected From Our Solar System?

The Fifth Planet sounds like a great name for a sci-fi movie -- perhaps a sequel to the 1997 movie "The Fifth Element." But the fifth planet may be real; a hypothesized giant world that was flung out of our solar system four billion years ago. It would have drifted tens of thousands of light years away by now.

Lees meer op Fox News.
Op Arxiv staat de volledige paper van David Nesvorny.

Er moeten heel wat "losgeslagen" "vrije" planeten door het heelal zweven. De betekenis voor ruimtekolonisatie? Deze uitspraak van Dennis May vind ik wel goed:

The next time some so called expert claims the stars are too far apart for interstellar travel to ever be practical - ignore that mindset. It would be like saying the Midwest will never be settled because there are no five star hotels between New York City and San Francisco.