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Mike Brown: Obvious attempt at snark is obvious. No it wouldn't suggest there are 200,000 earth sized planets in the outer solar system. Don't be absurd. The s

by xlm1717 11y ago

Mike Brown: Obvious attempt at snark is obvious. No it wouldn't suggest there are 200,000 earth sized planets in the outer solar system. Don't be absurd. The situation does seem reminiscent of how Clyde Tombaugh discovered Pluto (accidentally discovered a massive (compared to other nearby objects) outer solar system object in the Lowell Observatory telescope's tiny tiny field of view, no computer help either), but while it is possible that thousands of Kuiper Belt objects on the scale of Pluto exist (we've only discovered three or four so far because they would be so difficult to detect), hundreds of thousands of earth sized planets would have already collapsed gravitationally. Don't be absurd.

pklausler 11y ago
Mike Brown discovered those "three or four" Kuiper belt objects to which you refer (at least if you're thinking of Eris, Sedna, and Haumea) and has the credentials to snark all that he wants to. His book, "How I Killed Pluto And Why It Had It Coming", is a great read, highly recommended.
darkmighty 11y ago
His argument seems sound; I guess you may debate only the numbers. I would assign an a priori distribution of celestial objects on near the solar system concentrated on the the planetary plane, so this effect may compensate a narrow f.o.v. to some extent. Still, for a narrow enough field of view, you can make the argument that the probability of observation will be too low regardless of the a priori distribution details -- leading to the (possibly absurd) conclusion that many more planets probably exist. I'm just an amateur, but I believe old telescopes had a fairly wide f.o.v.; this is in part because their resolution doesn't even allow too much magnification. I assume they also had very flexible directing so you could survey large patches of the sky if necessary (and in particular you could concentrate around the planetary plane if you're eager for solar system objects).
mc808 11y ago
Another possibility (unless they've already ruled it out) is that it's a rogue planet passing through the Oort cloud. I don't know if thousands of them are any more plausible than thousands of gravitationally bound planets, but supposedly rogues outnumber star-bound planets. They would be spread pretty thin depth-wise and hard to detect.

by xlm1717 11y ago

pklausler 11y ago

Mike Brown discovered those "three or four" Kuiper belt objects to which you refer (at least if you're thinking of Eris, Sedna, and Haumea) and has the credentials to snark all that he wants to. His book, "How I Killed Pluto And Why It Had It Coming", is a great read, highly recommended.

darkmighty 11y ago

His argument seems sound; I guess you may debate only the numbers. I would assign an a priori distribution of celestial objects on near the solar system concentrated on the the planetary plane, so this effect may compensate a narrow f.o.v. to some extent. Still, for a narrow enough field of view, you can make the argument that the probability of observation will be too low regardless of the a priori distribution details -- leading to the (possibly absurd) conclusion that many more planets probably exist. I'm just an amateur, but I believe old telescopes had a fairly wide f.o.v.; this is in part because their resolution doesn't even allow too much magnification. I assume they also had very flexible directing so you could survey large patches of the sky if necessary (and in particular you could concentrate around the planetary plane if you're eager for solar system objects).

mc808 11y ago

Another possibility (unless they've already ruled it out) is that it's a rogue planet passing through the Oort cloud. I don't know if thousands of them are any more plausible than thousands of gravitationally bound planets, but supposedly rogues outnumber star-bound planets. They would be spread pretty thin depth-wise and hard to detect.