At 9 p.m., a battered S.U.V. rumbled up, and I got inside with a half-dozen other stargazers. On a moonless night, we barreled up rutted dirt roads for nearly an hour, climbing along switchbacks before reaching our destination, the privately run Pangue Observatory, which was seemingly the only structure for miles.

We were met by Eric Escalera, a retired French astrophysicist who formerly worked at nearby La Silla Observatory. “Government telescopes are actually very boring,” he said, leading us to an outdoor viewing platform and a 10-foot-tall telescope silhouetted against the sky like a piece of artillery. “They’re just for collecting data — you never actually get to see anything. This is more fun.”

On the isolated ridge, conditions were inky black, and it was impossible to see more than a foot or two ahead without a flashlight. Mr. Escalera motioned to the Milky Way, even gaudier up here, and pointed out two faint puffs of light nearby — distant galaxies more than 150,000 light years away known as the Magellanic Clouds.

To actually use Pangue’s 25-inch telescope (enormous for hobbyists, though puny, we were told, by research standards), it was necessary to climb a stepladder and look into an eyepiece at the top. Mr. Escalera first focused in on the Tarantula Nebula, a nursery for stars located inside the Large Magellanic Cloud. Through the mirror, the mass of gas and dust did indeed look like a giant spider, its body outlined by the nebula’s pale glow. (Don’t expect those brilliantly colored images of outer space that show up on screen savers and dorm-room posters; the real thing turns out to be much more subdued.)

As the night wore on, we took turns gazing at a creamy mass of stars called a globular cluster; Jupiter, with four of its moons and bands of tropical clouds; and an aging pair of stars called Eta Carinae, racing toward a violent end as a supernova. But the real show, at least for a novice like me, didn’t require a telescope at all. As midnight approached, the southern sky was a dense canopy of stars, packed tighter than I’d thought possible. A distant thunderstorm in Argentina sent up flashes of light from the east, while the screech of night birds cut through the darkness.

The next day, on a hot, cloudless morning, I continued my journey east on the Ruta de Las Estrellas. After Vicuña, the valley floor drops away dramatically and the drive turns into a twisting, roller coaster ascent. I passed adobe houses clinging to cliffside ledges and fruit stands selling fresh tuna, the fruit of the local cactus, before reaching the village of Pisco Elqui, a traditional favorite among Chilean vacationers that’s been enjoying a mini-boom in recent years.