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Comment by pavel_lishin | Hacker News Reader

Aren't we discovering that our solar system isn't very "ordinary" at all after detecting that most of the systems with extra-solar planets are very different from us?

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We keep getting less and less extraordinary the more we look. Whereas at the time of Asimov's or Sagan's writings (a few decades ago, the first exoplanet being detected in 1988) we didn't know of a single planet orbiting another sun, nowadays telescopes such as Kepler have pushed the estimate of the number of planets _just_ in the goldilocks zone to several billion inside the milky way. One in five sun-like stars may contain a planet capable of holding water:

http://www.latimes.com/science/la-sci-earth-like-planets-201...

https://en.wikipedia.org/wiki/List_of_potentially_habitable_...

https://www.universetoday.com/49605/how-common-are-solar-sys...

How do you figure? Are you thinking of the fact that most discovered planets are gas giants? This is due to the sensitivity of our equipment moreso than an insight about the distribution of planets in the universe.

I think you're right about that.

Do you have references on that? I was under the impression that as our detection improved, the systems we found around stars like ours were starting to look increasingly like ours. (But, at the same time it's looking like smaller, colder stars may have the bulk of inhabitable planets.)

This articles concludes that we are average, but I don't really understand how - we're only average in age, but we differ in just about every other data point (no super earths, low-eccentricity orbits, no close-in planets): http://aasnova.org/2015/09/25/how-normal-is-our-solar-system...

This article says we're definitely weirder, but points out that the detection technology matters, and we may not have the full picture yet: https://planetplanet.net/2016/07/12/exactly-how-unusual-is-o...

Exactly, we're weird only in that we can only detect weird planetary systems right now. The super earths, super Jupiter type systems are so common if only because that is where our light detection is best right now.

Until we start getting probes out to solar systems or have some way to detect orbits of planets that aren't perpendicular to our own we won't have much of an idea how weird we truly are or aren't.

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