In 1962, European countries joined forces to establish an international astronomical project. They set up a space observatory, with some of the most powerful telescopes in the world, at La Silla, in which southern country?

The search for the perfect place to view the southern celestial hemisphere led astronomers to the outskirts of Chile's Atacama Desert. In 1962, several European nations formed the European Southern Observatory (ESO) with the goal of building a world-class astronomical facility. The region's high altitude, exceptionally dry air, and remote location offer some of the clearest and darkest night skies on the planet, making it an ideal site for powerful ground-based telescopes.

The chosen (Review) site was a 2,400-meter-high mountain named La Silla, which means "The Saddle" in Spanish, due to its distinctive shape. This became ESO's first major observatory, and for decades it was a hub of astronomical discovery. It is home to several important instruments, including the venerable 3.6-metre telescope (Deals) and the groundbreaking New Technology Telescope (NTT), which pioneered the active optics technology now standard in all large modern telescopes.

The success of La Silla cemented Chile's reputation as the world's foremost location for astronomy and paved the way for even larger ESO projects in the country, like the Very Large Telescope. Among its many achievements, observations at La Silla were crucial in the 1995 discovery of 51 Pegasi b, the first confirmed exoplanet orbiting a Sun-like star, a finding that later earned a Nobel Prize in Physics.