An astrophysicist making remarkable discoveries. Developers of apps that teach violin and investing to young people and that thwart big-game poachers. Inventors of a digital health screening tool and a website to connect minority professionals. A community activist. The head of a startup bringing electric scooters and bike shares to cities. A young lawyer making his mark at a big firm. What they all have in common? They’ve yet to see their 30th birthday. Meet the impressive 2020 class of 20 In Their 20s.