Planet Y: New Earth sized hypothetical planet in the Kuiper Belt livescience.com 3 points by pfdietz 8 hours ago
pfdietz 7 hours ago An Earth-sized planet at 100 AU could retain helium in its atmosphere, and so might be the best place in the solar system to extract the useful isotope He-3.
An Earth-sized planet at 100 AU could retain helium in its atmosphere, and so might be the best place in the solar system to extract the useful isotope He-3.