Space station photos reveal Earth’s ‘bloody’ lakes

Astronauts aboard the International Space Station have captured a “bloody” phenomenon running through some of Earth’s lakes.

They took photos showing bodies of water colored red due to the abundance of algae and bacteria lurking in the water.

A photo released at NASA’s Earth Observatory shows Laguna Colorada, also known as the Red Lagoon in the Bolivian Andes, from above. This lagoon is famous for its bright red appearance, and according to local legend, the lake is not filled with water at all, but rather with the blood of the gods.

The reddish hues are characteristic of hypersaline environments, where bodies of water are typically saltier than normal seawater. There are so many red algae and other microorganisms in these lakes that they color the water brightly.

Laguna Colorada
The Laguna Colorada or Red Lagoon in Bolivia seen from space. The lake has a bright red color due to algae and other microorganisms.
SS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center./NASA Earth Observatory

In some lakes this algae growth grows more strongly than in others. Its growth depends on several factors, including water temperature, light and the salinity of the water. The algae in Laguna Colorado are an important food source for flamingos that come to the water to eat.

Another image taken by the astronauts shows the Betsiboka River Delta in Madagascar, showing water flowing in red and brown colors.

Betsiboka River Delta
The Betsiboka River Delta in Madagascar seen from space. it bleeds red water into the ocean.
SS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center./NASA Earth Observatory

The redness of this river and other bodies of water in Madagascar is caused by the iron-rich sediment, NASA Earth Observatory reported.

Many images of these bloody waterways have already been captured by satellites and astronauts. According to a previous report from NASA Earth Observatory, an astronaut said in a meeting with the president of Madagascar, “Oh yes, I know your country. It is the land bleeding into the ocean.”

The sediment flows through the river and sometimes clogs waterways. Occasionally, however, new islands arise on which mangroves grow.

While the bloody color may look strange, some algae provide important water sources for bird species and marine life.

In the Betsiboka River Delta, the seagrasses in the estuary provide food for endangered green sea turtles and manatees.

Too much algae in the water can be harmful. Red tide, for example, is a type of algae bloom that grows quickly and can turn water bodies bright red. High concentrations of this algae can be toxic to marine life. Warmer waters influenced by climate change can lead to severe red tides in lakes and rivers.

Numerous red algae have also bloomed in the Great Salt Lake in Utah in the past.

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