LLANO DE CHAJNANTOR, Chile — Trucks stall on the road to this plateau 16,597 feet up in the Atacama Desert, where scientists are installing one of the world’s largest ground-based astronomical projects. Heads ache. Noses bleed. Dizziness overcomes the researchers toiling in the shadow of the Licancabur volcano.

“Then there’s what we call ‘jelly legs,’ ” said Diego García-Appadoo, a Spanish astronomer studying galaxy formation. “You feel shattered, as if you ran a marathon.”

Still, the same conditions that make the Atacama, Earth’s driest desert, so inhospitable make it beguiling for astronomy. In northern Chile, it is far from big cities, with little light pollution. Its arid climate prevents radio signals from being absorbed by water droplets. The altitude, as high as the Himalaya base camps for climbers preparing to scale Mount Everest, places astronomers closer to the heavens.

Opened last October, the Atacama Large Millimeter/submillimeter Array, known as ALMA, will have spread 66 radio antennas near the spine of the Andes by the time it is completed next year. Drawing more than $1 billion in funding mainly from the United States, European countries and Japan, ALMA will help the oxygen-deprived scientists flocking to this region to study the origins of the universe.