https://hackerpaper.kaipfister.de/p/1208.5709/Collected HN comments and submissions linking this paper.enMon, 02 Nov 2026 11:16:22 GMThttps://news.ycombinator.com/item?id=4642234urn:hackerpapers:mention:1208.5709:4642234Thu, 11 Oct 2012 19:08:23 GMT<p>Here&#x27;s the paper. http://arxiv.org/pdf/1210.2720.pdf It&#x27;s reasoned guess. They know three things about the planet: its mass, its size (radius/volume), and its orbital distance. They also know some of the chemistry of the star it orbits. From the mass and radius, they inferred the density of the planet is a lower than other rock planets. They can explain low density in several ways. One is a thick layer of low-density supercritical water on the surface. Very large, extremely hot &quot;oceans&quot;. An alternative is low-density graphite or diamond inside the mantle. What they show is that a carbon…</p><p><a href="https://hackerpaper.kaipfister.de/p/1208.5709/">Paper and discussion history</a>. A mention is not an endorsement.</p>astro-ph.EP