Bohdan Paczynski

Bohdan Paczynski was renowned for his pioneering theoretical work on gravitational microlensing and gamma-ray bursts. He proposed that massive objects could act as cosmic lenses, allowing astronomers to detect dark matter and exoplanets. His theories led to real-world astronomical surveys like the Optical Gravitational Lensing Experiment (OGLE).

After defecting from his native Poland, Paczynski spent the latter half of his career at Princeton University in New Jersey. He joined the Princeton faculty in 1982, holding the title of Lyman Spitzer Jr. Professor of Theoretical Astrophysics. At Princeton, he produced much of his groundbreaking work on the nature of the universe.

While he did not personally discover the first exoplanet, Paczynski laid the theoretical groundwork for using gravitational microlensing to find them. He actively championed the technology and methods that allowed telescopes to spot planets orbiting distant stars. His efforts made microlensing a standard and successful technique in modern exoplanetary astronomy.

In the 1990s, Paczynski argued forcefully that gamma-ray bursts (GRBs) were of cosmological origin, meaning they occurred in incredibly distant galaxies. This opposed the prevailing theory that GRBs originated within our own Milky Way galaxy. His bold hypothesis was definitively proven correct in 1997 by satellite observations mapping the bursts to distant galaxies.