Roman Gerasimov

In cluster M15, the first generation of stars shows a spread in heavy elements, while the second does not. This means the gas for the first stars was poorly mixed. This helps us understand where elements like gold are born: most likely in neutron star mergers, which happen quickly.

Using Webb, astronomers peered into the atmosphere of the brown dwarf Wolf 1130C and found phosphine — a gas familiar from Jupiter. Its abundance is ten times higher than expected, pointing to vigorous mixing of layers, like in a planetary mixer. Now the boundary between giant planets and brown dwar