Physicists have simulated the cores of some large rocky exoplanets by pummeling iron with lasers. The resulting measurements give the first clue to how iron might behave inside planets outside the solar system that are several times the mass of Earth, researchers report April 16 in Nature Astronomy.
“Until now, there’s been no data available on the state of these materials at the center of large exoplanets,” says Ray Smith, a physicist at Lawrence Livermore National Laboratory in California.