kolektiva.social is one of the many independent Mastodon servers you can use to participate in the fediverse.
Kolektiva is an anti-colonial anarchist collective that offers federated social media to anarchist collectives and individuals in the fediverse. For the social movements and liberation!
I like "People's History of Science," and "Gay Berlin." The latter isn't technically about science, but does talk a lot about Magnus Hirshfeld, and the world's first trans medical clinic.