Discovery of a big void in Khufu's Pyramid by observation of cosmic-ray muons

Understand

The Great Pyramid or Khufu's Pyramid was built on the Giza Plateau (Egypt) during the IVth dynasty by the pharaoh Khufu (Cheops), who reigned from 2509 to 2483 BC.

• Despite being one of the oldest and largest monuments on Earth, there is no consensus about how it was built.
• To better understand its internal structure, we imaged the pyramid using muons, which are by-products of cosmic rays that are only partially absorbed by stone.
• The resulting cosmic-ray muon radiography allows us to visualize the known and potentially unknown voids in the pyramid in a non-invasive way.