Thirty specialists from the Egyptian Ministry of Tourism and Antiquities and the University of Tübingen have spent five years cleaning the ceiling in the Temple of Esna, south of Luxor, in Egypt. Thousands of years of dust, soot, and bird droppings were carefully removed to reveal the intended appearance of the art underneath. One of the paintings revealed depicts the new year as it was designated in ancient Egypt. The "before" picture is above; see the stunning difference in the "after" image.
This is only one of seven astronomy- and calendar-themed sections of the ceiling, and it depicts the Egyptian new year. The three gods shown are Orion, representing the constellation, Sothis, the Egyptian name for the constellation Sirius, and Anukis, who is responsible for making the Nile floodwaters recede. The Egyptian new year was when Sirius becomes visible in the night sky and the Nile begins to flood. The other details and hieroglyphic labels also lend meaning to the painting.
That's an amazing feat, but it's just the ceiling. The team will next tackle cleaning the walls, also covered in ancient art, which will also takes years to complete.
(Images credit: Ahmed Amin/Ministry of Tourism and Antiquities (MoTA))