The Atacama Desert of northern Chile is the driest place in the world . But it has always proved fertile ground for Patricio Guzman, the Chilean documentary filmmaker, who first filmed there 40 years ago and has now returned to make “Nostalgia for the Light,” a meditation on astronomy, archaeology, geology and human rights.

“The Atacama is where many elements of our past are concentrated,” Mr. Guzman, 69, said in a recent interview. “Not just the past of Chile, but of the Earth and even the galaxy. I’d been wanting for the longest time to make a film that brought all of this together .”

What finally enabled Mr. Guzman to make the film, which opened in several countries last year and is now playing in the United States, was his realization that the subjects did have a point in common: the preservation of memory. The women who search the desert for the remains of loved ones who disappeared under General Augusto Pinochet’s dictatorship share the trait with the archaeologists and geologists who work in the shadow of Atacama’s observatories.

Remembrance has also been the main theme of Mr. Guzman’s own, primarily political, work. But his best-known film, “Battle of Chile,” has come to be regarded as something more than just the record of a particular historical moment.

“The way in which Guzman understands that historical consciousness is elusive and impossible to fix is one of the most vital contributions he has made, and it all begins with ‘Battle of Chile,’ ” said Haden Guest, director of the Harvard Film Archive. “Like Claude Lanzmann he is interested not just in the past but the past in the present .”

In some ways “Nostalgia ” represents a return to Mr. Guzman’s origins. He began, Mr. Guest noted, “as a writer of science fiction, which gives him a certain visionary quality and an acute understanding of paradox.” As a child in Santiago, Mr. Guzman read Jules Verne and memorized the constellations.

“I think that in this film I felt more free,” said Mr. Guzman, who now lives in Paris. “In treating the desert and the cosmos, I found more possibilities for metaphors and for metaphysical, philosophical reflection. I was faced with a horizon that allowed me to develop a kind of poetry that I’ve always had in me but have never had a chance to show.”

In the film, for instance, Mr. Guzman’s camera moves between photographs of asteroids and shots of bone fragments of Pinochet victims who remain unidentified. The two are indistinguishable, underlying his notion of the cosmos as a unified whole comprising “the same material.”

The Allende government’s socialist experiment was and remains Mr. Guzman’s focus. “We first met during the Allende period ,” recalled Ariel Dorfman, the Chilean writer. “He went to the places which were most dangerous, but also to those not on the radar. He was always willing to take risks.”

His relationship with his homeland, which he left after being imprisoned during the 1973 coup that overthrew Allende, remains complicated and ambiguous. As he notes, he has now “lived more time outside Chile than in it.” But he also remains profoundly connected by remembrances that he cannot ? and does not want to - discard.

“I believe that each of us carries a mental knapsack, in which we store the memory of our parents, our first communion, the first day at school, graduation day, perhaps the death of those parents, the first girlfriend,” he said. “That never leaves. It’s stuck to us. So it really doesn’t matter where you are.”


By LARRY ROHTER