Growing up in the Swiss Alps, Fritz Zwicky liked to throw rocks across rivers, and snowballs at church steeples. He just wanted to throw things higher and farther than anyone else.

Decades later, Zwicky became the first person to throw something away from Earth — a metal ball bearing blasted from the nose cone of a rocket. It escaped Earth’s gravity and went into orbit around the Sun. It was the first step in a grand plan to explore the solar system.

Zwicky was born 125 years ago today, in Bulgaria. After earning his doctorate in astronomy, he joined the Mount Wilson and Palomar observatories in California.

At the time, any star that suddenly flared into view was called a nova. But in the late 1920s, Zwicky realized that not all of these stars are alike. Some are far more powerful than others, so they’re called supernovas. Zwicky and a colleague also realized that a supernova should leave behind a crushed corpse, called a neutron star. The first one was discovered more than 30 years later.

Zwicky also served as research director at Aerojet Engineering. He studied jet engines, solar-powered furnaces, and colonies on the Moon. And he devised a five-step plan for human expansion into space — from “throwing” pellets farther into space, to reworking the planets and moons of the solar system to make them habitable.

The first four steps have all come about. But the last is still a bit more than a stone’s throw into the future.
 

Script by Damond Benningfield