This artist’s impression shows the planet K2-18b, it’s host star and an accompanying planet in this system. K2-18b is now the only super-Earth exoplanet known to host both water and temperatures that could support life. Could habitable worlds like this have formed before galaxies formed? Image Credit: ESA/Hubble, M. Kornmesser
What came first, galaxies or planets? The answer has always been galaxies, but new research is changing that idea.
Could habitable planets really have formed before there were galaxies?