How Radioactive Elements May Make Planets Suitable or Hostile to Life

When describing exoplanets that are potentially promising candidates for life, scientists often use the terminology of the "habitable zone."  This is a description of planets in orbit where temperatures, as predicted by the distance from the host star,  are not too cold for liquid water to exist on a planetary surface and also not to …

The Interiors of Exoplanets May Well Hold the Key to Their Habitability

The quest to find habitable -- and perhaps inhabited -- planets and moons beyond Earth focuses largely on their location in a solar system and the nature of its host star,  the eccentricity of its orbit, its size and rockiness, and the chemical composition of its atmosphere, assuming that it has one. Astronomy, astrophysics, cosmochemistry …