He gained a great deal of useful experience from his studies in theoretical physics at Niels Bohr's Institute close by, and he was at the right place at the right time.

Going abroad for 18 months meant a lot to the young researcher, and when he went back to Denmark and to the rising national socialism in Europe, he succeeded his father's professorship in 1940.

But after the Second World War, Bengt Strömgren became tired of lacking state funding for the project, and with a stagnant national economy, he felt that he had to leave Danish research, which he did in 1951.

He stayed at Princeton with his family until 1967, when he went back to his homeland Denmark, and became the next to the last resident in a series of great Danish scientists of the Carlsberg Mansion and Honor, which had earlier been occupied by Niels Bohr among others.

Just before the war, he discovered the so-called Strömgren Spheres — huge interstellar shells of ionized hydrogen around stars.