Over 1,000,000 Earth like planets in our Galaxy … wow

OK, to follow up from my previous post, in the excitement I got the numbers wrong, so here are the real numbers …

First the facts …

  • Kepler has been staring at one part of the sky, continuously looking at 156,000 stars, we have 100-400 Billion in our galaxy, its a truly tiny sample.
  • Keplar has come up with 1235 candidate planets
  • Of these, 68 are roughly Earth-sized, 288 are bigger than Earth, 662 are roughly Neptune-sized, 165 are Jupiter-like, and 19 are larger than Jupiter.
  • 54  (out of the 1235) are in their stars’ habitable zones …this is the bit I got wrong … only five of these are near-Earth sized, and only one is actually very close to Earth’s size!

OK, now lets start to extrapolate from the above numbers. [In the next bit below its just an indication of what might be out there, so please digest with a planet sized lump of salt] Since Kepler only watched 156,000 stars out of the 100-400 Billion in our galaxy (OK, lets be cautious and say just 100 Billion), then that allows us to extrapolate up by 641,025 … and that gives us some staggering numbers …

  • 791 Million Planets in our galaxy
  • 10.6 Million of those are earth sized
  • Given our 5 near-earth sized and 1 earth sized planet in the Goldilocks zone … then with an extrapolation multiplier of 641,025 … it truly does hint that we have over 1,000,000 million earth-like planets in our Galaxy alone [And I’m not stretching it, I’m really pressing these numbers down, it could be a lot higher]

OK, one final thought. If there are that many earth-like planets in our galaxy alone, then what about the rest of the universe? There are at least 100 Billion other Galaxies out there.

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