Exploring the Planet-Metallicity Connection with CKS

Happy to announce that the latest paper in California-Kepler Survey has been published in the Astronomical Journal (Petigura et al. 2018). This paper examines the association between a star's chemical composition and the number and type of planets that form. We found that stars rich in heavy elements harbor the greatest diversity of planets. Stars are mostly made from hydrogen and helium, but they contain trace amounts of other elements like carbon, oxygen, nitrogen, iron, etc—elements that make up the the Earth, life, and us. We can measure the amount of different elements in a star by analysis absorption lines in its spectrum. To astronomers, every element other than hydrogen and helium is