MINNEAPOLIS (WCCO) — A famous doctor says his training at Hennepin County Medical Center not only prepared him for a career in ER medicine, it also prepared him for space.

Kjell Lindgren finished his ER residency at HCMC, then became a NASA Astronaut. He returned from his mission to the International Space Station in December.

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On Wednesday, he came back to read a space-themed book to some patients at HCMC. He explained how his work at HCMC was similar to his work in space.

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“We have to make decisions with incomplete information that have critical outcomes, life and death outcomes. We have to work very closely with teams of highly skilled people for very important tasks,” Lindgren said.

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While Lindgren was in space, he tweeted out this photo of Minneapolis. He says he used a very long lens.