QUICK FACTS
Where is he? Dek and Daga, Ethiopia (11.907552854, 37.285011102)
What’s in the photo? A pair of islands in the middle of green colored Lake Tana
Who took the photo? An anonymous astronaut aboard the International Space Station
When was it taken? January 2, 2017
This fascinating astronaut photo shows two islands in the murky green waters of a large African lake. Both continents are home to monasteries that house important religious relics, including the remains of several ancient emperors.
The two islands, named Dek and Daga, are located in Ethiopia’s largest body of water, Lake Tana, which has an average surface area of about 1,200 square miles (3,100 square kilometers), about the same size as Rhode Island. The lake, designated a UNESCO biosphere reserve, is located in the Ethiopian highlands, approximately 5,800 feet (1,770 meters) above sea level, and has a maximum depth of approximately 50 feet (15 m).
Lake Tana was formed about 5 million years ago when volcanic activity dammed a group of ancient rivers. Today it is the main source of the Blue Nile, a 1,450 kilometer tributary of the Nile that flows through Ethiopia and Sudan.
Dek, the larger of the two islands, is approximately 7.5 km in diameter at its widest point and has a population of approximately 5,000, while Daga has a maximum width of approximately 1.6 km and is not permanently inhabited.
Seen from above, the islands stand out against the lake’s bland milky green color, the result of algae blooms that thrive on nutrients from agricultural runoff and sewage, according to NASA Earth Observatory.
Related: Check out all the best images of Earth from space
Dek is an agricultural hotspot thanks to its nutrient-rich volcanic soils and high rainfall, due to its location in the Intertropical Convergence Zone – a belt of low pressure near the equator that experiences frequent thunderstorms. Most of the island’s surface has been transformed into agricultural fields, which appear light brown and red when viewed from above. Their main crops are corn, millet, coffee and mangoes.
In the photo, a bright orange lake is located towards the southeast corner of Dek. It’s unclear exactly what gives this lake its vibrant hues, but it’s likely also linked to agricultural runoff, according to the Earth Observatory.
However, the most interesting sites on both islands are probably their monasteries, which are difficult to see from space.
Sacred relics
Experts estimate that there is at least one church or monastery on more than half of Lake Tana’s 30 or more islands (the total number of islands in the lake is disputed because some only appear during the rainy season, when the lake expands). These religious sites were created, in part, to protect Ethiopia’s most precious relics and treasures during times of war, according to the Earth Observatory.
Dek is home to at least five churches, as well as the 18th-century Narga Selassie Monastery, which is full of stunning paintings of Ethiopian history. However, Daga is arguably home to a more important monastery, named Daga Estifanos or “Saint Stephen of Daga”, which dates from the 13th century.
The mummified remains of at least five Ethiopian emperors – who ruled the country at different times between 1270 and 1730 – are kept at Daga Estifanos and are each on display to tourists in special glass-walled coffins, alongside crowns, scrolls and other items from their reigns, according to the Lake Tana Biosphere Reserve website.
But, due to local customs, only men are allowed to visit Daga and its monastery. In fact, the local “no females” rule is even applied to farm animals.
Other major religious sites in Lake Tana include Tana Cherkos, an island populated exclusively by monks of the Ethiopian Church. THE Ark of the Covenant was believed to have been kept there for about 800 years, sometime after being stolen from Jerusalem and before being moved to the Ethiopian mainland, according to the Lake Tana website.