There’s more to the universe than meets the eye, he found. His studies led astronomy to the dark side, changing our view of what’s out there.

Jeremiah Ostriker, an astrophysicist who helped set off a revolution in humankind’s view of the universe, revealing it to be a vaster, darker realm than the one we can see, ruled by invisible forms of matter and energy we still don’t understand, died on Sunday at his home on the Upper West Side of Manhattan. He was 87.

His daughter Rebecca Ostriker said the cause was end-stage renal disease.

Over more than four decades, mostly at Princeton University, Dr. Ostriker’s work altered our understanding of how galaxies form and evolve as he explored the nature of pulsars, the role of black holes in the evolution of the cosmos and what the universe is made of.

Before the 1970s, most astronomers believed that galaxies were made up mostly of stars.

“Ostriker was arguably the most important single figure in convincing the astronomical community that this natural and seductive assumption is wrong,” David Spergel, the president of the Simons Foundation, which supports scientific research, wrote in 2022, nominating Dr. Ostriker, his mentor, for the Crafoord Prize, the astronomical equivalent of a Nobel. He cited Dr. Ostriker’s “eloquent advocacy for the then-radical new model in which the visible stars in galaxies were only a minor pollutant at the center of a much larger halo of dark matter of unknown composition.”

Dr. Ostriker’s work, he said, was “the grandest revision in our understanding of galaxies” in half a century.

Dr. Ostriker in 1983 in Harvard Square in Cambridge, Mass. He had planned to study chemistry there but switched to physics, which appealed to what he called his “cosmic perspective.” He graduated in 1959.Rebecca Ostriker

Jerry Ostriker, as he was known to friends and colleagues, a man with a prickly sense of humor and a soft but commanding voice, was willing to go wherever the data and scientific calculations led him, and was not shy about questioning assumptions — or having fun. Prominently displayed in his home was a photo of himself, taken during a sabbatical in California, driving a moped with a bottle of wine in hand.

We are having trouble retrieving the article content.

Please enable JavaScript in your browser settings.


Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.


Thank you for your patience while we verify access.

Already a subscriber? Log in.

Want all of The Times? Subscribe.