Kepler Discovers Twin Water Worlds

Last week, I was planning to write two new “planet profiles” to add to our collection of planet ideas here at SciFi Ideas when I received some interesting news. My idea was to invent two water worlds, one warm and one cold, that would orbit the same star at different distances. I had thought that these might make interesting colony worlds, with the warmer planet as an ocean paradise and popular tourist destination, and the cooler planet as maybe a deep sea mining world.

But before I could put finger to keyboard on this idea of twin ocean planets, I was surprised to learn that NASA’s Kepler observatory had beaten me too it, discovering a pair of twin water worlds in exactly the configuration I had in mind.

Now, I know that art imitates life, and that science fiction has a tendency to preempt scientific discoveries, but I was surprised by just how quickly Kepler has gazumped me on this one. I only wish I’d written the planet profiles sooner.

The two recently discovered planets – Kepler-62e and Kepler-62f – orbit a star slightly smaller than the sun and have been described as two of the most likely locations for life beyond the solar system so far discovered. Both are thought to be covered by vast oceans, but it is not yet known whether they have a rocky sea floor beneath.

The Kepler-62 planetary system contains at least 5 planets, our twin water worlds being the fourth and fifth planets from the star. Kepler-62e sits comfortably within the star’s “habitable zone” making it nice and warm. Its counterpart, Kepler-62f, orbits at the outer edge of the habitable zone and is therefor much colder. In fact, Kepler-62f would require a greenhouse effect in its atmosphere to prevent its ocean from freezing; without this atmospheric blanket the planet would likely have a frozen surface like that of the Galilean moon Europa.

These twin water worlds aren’t exactly as I had imagined for my two watery colony worlds; both are larger than the Earth and have been classified as “super-Earths” (the smallest, “e”, being 61% larger than the Earth). That might cause a slight gravity problem for potential maritime colonists.

It is also too soon to tell if the atmospheres of these worlds would be breathable to us humans. In fact, the composition of their atmospheres would likely depend on whether or not life exists their oceans. There seems to be a lot of guess work involved in this kind of planetary discovery, but all indicators are that conditions on both worlds are likely to be conducive to some kind of life, if not human life.

Could the twin ocean worlds of the Kepler-62 system become future colonies of mankind? Are these real-life manifestations of the hot and cold life-bearing planets of my imagination? It’s too early to tell, but I’m sure we’ll all be keeping a curious eye on this very interesting planetary system, which lies 1,200 light years from our own.


If you want to learn more about these planets and other potentially habitable worlds, I recommend you check out the Habitable Exoplanets Catalog on the website of the Planetary Habitability Labratory (University of Puerto Rico).

Article written by Mark Ball.

  • It’s fascinating to hear about these planets and others being discovered but it’s a huge shame that nothing can be done to reach them in our lifetime.

  • Ben Martin

    Unless FTL or something faster like bending the space-fabric is invented soon… oh… wait… pure sci-fi concepts.
    Hum, I guess we need to keep exercising our imagination on the issue. (nice mixers on the profile photo).

  • Axel Clavier

    Well, the Alcubierre drive, similar to the warp drive from Star Trek, is a real mathematical theory: Alcubierre

    • Jos van Egmond

      It’s real, but the chances of the drive to be impossible to build or use are real as well.