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I said I'd do a thread about my new Space Science Reviews paper, so here it is! This is part of a collection of papers arising from a meeting at the International Space Science Institute in Bern in 2024: a workshop to better understand rocky extrasolar planets. A 🧵:

The basic idea is that we're finding more and more exoplanets, including ones that—on the basis of radius and mass—are surely rocky. But that's usually all we have, even though it's tempting to call them "super-Earths" or to otherwise attribute (intentionally or not) certain properties to them.

A big part of the paper (and my career) is comparative planetology, the comparing of one world with another. So in this paper, we talk about how and when the crusts of these worlds developed. Those of Mars, Mercury, and the Moon are ancient; some of Earth is very recent. And Venus?? who tf knows

We take a deep dive into Earth in particular—since it's the world we understand best (even if there's LOTS about Earth we still *don't* understand). Here's a plot showing how we think Earth's bimodal crust grew through time; continental crust wasn't always there, but oceanic crust probably was.

A big part of the paper is the distribution and formational history of the major geological elements of Solar System worlds. So we included these maps, which show things like volcanoes, tectonic systems, etc. As our baseline case, this is modern Earth.