A newly published study has dated the Ames impact structure in Oklahoma to nearly 370 million years ago. ^[2] The work appears in the journal Meteoritics & Planetary Science. It uses new radioisotopic constraints to refine the chronology of asteroid impacts on the North American continent. In separate work published this week, researchers found formaldehyde rained onto ancient Mars between 3.6 and 3.8 billion years ago. The study, led by Shungo Koyama, noted the compound was concentrated over former water bodies on the planet. ^[3] An international collaborative team also published a planetary science paper in Astronomy & Astrophysics on 4 October. Authors were drawn from research institutions in Mexico, Italy, Spain and the United States. ^[1]