Lights of Uritorco
Glowing lights seen on and above Cerro Uritorco, the highest peak of the Sierras Chicas, are the area's most frequent mystery; in the 1990s geophysicists offered tectonic stress as an explanation.
1990 CE · -30.84, -64.48 · status: disputed
The account
Reports of lights on the mountain go back to the start of UFO tourism in the 1980s (the year here marks the 1990s debate). The 'tectonic strain' theory of J. S. Derr and Michael Persinger, which proposes that stressed rock can release luminous phenomena, was informally applied to the 'Luces del Uritorco'.
The sceptical view
The tectonic-strain hypothesis itself is contested. Many lights on a well-visited mountain are simply hikers' torches, vehicles and campfires.
The researched reading
Lights on a popular, mythologised mountain. Human lights and expectation explain most reports, and no measured anomaly has been recorded.
| Explanation | Weight | Why |
|---|---|---|
| Something in the surroundings | 38% | Cerro Uritorco is a busy hiking mountain above a town that markets UFO tourism; headlamps, campfires, vehicles on surrounding roads and torches on the summit at night account for many lights. |
| A cultural story | 26% | Capilla del Monte has built an identity around Uritorco, the "lost city of Erks" and UFO lore; the tradition shapes what visitors look for and report. |
| Perception, memory or mind | 14% | Expectant watchers in the dark see distant lights move through the autokinetic effect, and stars and planets near ridges become "lights on the mountain". |
| A known natural phenomenon | 10% | Lightning, distant storms and stars setting behind the ridge produce lights on the skyline. |
| A hoax or fabrication | 6% | Some tourism-linked photographs and stories are staged or exaggerated. |
| Genuinely anomalous | 6% | The Derr–Persinger tectonic-strain idea is unproven and has not been tested at Uritorco; there is no instrumented record of unexplained lights. |
Official position: No official investigation; the tectonic-strain idea was applied informally and never tested on site.