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The Pfizer–BioNTech vaccine has passed safety and efficacy tests — but researchers still have many questions about how this and other vaccines will perform as they’re rolled out to millions of people.
As NASA prepares to launch the first spacecraft that will collect samples from Mars, Nature looks at back at missions that have grabbed extraterrestrial material.
Nature examines how viral diagnostic tests work, why testing has varied around the world and the CRISPR-based tests under development to fight COVID-19.