A controversial experiment to artificially cool Earth was canceled — what we know about why

Cambridge, MA - January 24: Gated entrance on the campus of Harvard University. | Photo: Getty Images After years of legwork, Harvard researchers canceled plans to test a controversial theory for cooling the planet by sending sunlight-reflecting particles up into the atmosphere. Now, members of an independent advisory committee tasked with addressing ethics and safety concerns are sharing what they learned from the ill-fated project.
A policy analysis published in the journal Science on Friday h