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Scientist

Maarten Schmidt

1929- · astronomy, astrophysics
Dutch-American astronomer who in 1963 deciphered the spectrum of the mysterious object 3C 273 and discovered quasars — the most distant and powerful sources of radiation in the Universe. This discovery radically changed ideas about the scale and evolution of the cosmos.

Biography

Born in Groningen, Netherlands. Studied astronomy at Leiden University under Jan Oort, one of the pioneers of radio astronomy. In 1959, moved to the USA and began working at the California Institute of Technology. Became professor of astronomy at Caltech, later directed the Hale Observatories. Member of the U.S. National Academy of Sciences. Awarded the Bruce Medal, the Henry Norris Russell Lectureship, and other honors. The asteroid 10430 Martschmidt is named after him.

Key discoveries

💡 Schmidt had long been unable to understand the spectrum of 3C 273 until he realized that the Balmer series lines were strongly redshifted. The insight came to him while driving home. He later said that the discovery process was like assembling a puzzle without a picture — the pieces suddenly came together into a single image.
"He recalled that when he realized the lines in the spectrum of 3C 273 were ordinary hydrogen lines, only shifted by 15%, he felt as if struck by lightning, meaning the object was billions of light-years away."
Concepts
active galactic nucleusexpansion of the universequasarspectroscopy
Laws
Hubble's law
Scientists
Robert HookeJohann Jakob BalmerJocelyn Bell BurnellArno PenziasCharles TownesJames Clerk MaxwellErwin SchrödingerCecilia Payne-Gaposchkin

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