Archaeologists in Peru have uncovered a structure at Áspero that appears to have been used to observe the sky, adding detail to what is known about early scientific practices in the Caral Civilisation.
The find was announced by the Caral Archaeological Zone, with fieldwork led by Ruth Shady Solís. The team has been investigating the coastal settlement for more than two decades.
Áspero lies near the Pacific coast in Supe Puerto and dates to between 3000 and 1800 BC. It is considered one of the main coastal centres linked to Caral, a society often described as one of the earliest in the Americas.
The newly recorded structure sits in Sector J1, close to larger pyramidal buildings. From this point, there are clear views of the shoreline and the lower Supe Valley. Researchers think that position mattered. It would have allowed regular observation of the horizon, the movement of the Sun and Moon, and changes affecting the sea.

Excavations show that the structure went through several stages. In its earliest phase, it appears to have been a public or ceremonial space. Later, a circular platform was added, just over three metres across, with a standing stone set at its centre. Stones of this kind, known as huancas, are often linked to ritual use in the Andes.
Further modifications followed, including the construction of a double-stepped platform with a broader lower tier and a smaller upper level. At its centre was a rectangular stone, with an adjacent enclosed area containing a hearth. Together, these features indicate continued use of the space, likely linked to repeated gatherings or formalised activity.
Researchers suggest the layout may have been used to track cycles in the sky. Watching the Sun, Moon and stars would have helped people judge seasonal change. For a settlement dependent on fishing and shellfish, timing mattered. Tides, weather and marine life do not stay constant, and small shifts could affect food supply.
At some point, the structure was covered and reused for domestic purposes. That change suggests its earlier role had come to an end.

Áspero itself covers nearly 19 hectares and includes more than 20 architectural complexes. Its position near the sea made it well placed for fishing, but it was also part of a wider network. Goods moved between the coast and inland areas, linking communities with different resources.
Previous finds at the site include high-status burials, among them the so-called “Lady of the Four Tupus”. Such discoveries point to a society with clear social ranking and organised activity.
The latest work adds another element. It suggests that observing the sky was not separate from daily life. Instead, it formed part of how people organised work and responded to their surroundings.
Researchers are examining the structure’s alignment, layers of construction and associated materials. These will be compared with dating evidence to clarify when each phase was in use.
Sources : Peruvian State

