The Nile River runs blood red in images captured by the European Space Agency’s new Sentinel-3A satellite. While the stunning images of the storied Nile River come from sophisticated scientific instrumentation, they have many observers recalling ancient legends of biblical times.
Sentinel-3A was launched by the European Space Agency (ESA) on February 16, 2016. The Sentinel-3A satellite just recently began to transmit data back to earth, including the stunning image that includes the Nile River. The image just released by the ESA was recorded on March 3, 2016, and includes the Sahara and other desert areas of northeast Africa and the Middle East, featuring the delta area along with the Nile River itself.
The legendary Nile River runs from central Africa and the Ethiopian highlands through 11 countries, including South Sudan, Sudan, and Egypt into the Mediterranean Sea. Best known outside the African continent for its association with ancient Egypt, the Nile River appears distinctly in the satellite images. The Egyptian city of Cairo is visible at the center of the satellite image, with the Nile River winding northwards on its way to the Mediterranean. The Red Sea, Crete and other islands of the Mediterranean Sea are also visible in the images.
Why is the Nile River red in the image? The Sentinel-3A uses a sensitive and complex system of instrumentation that has been designed to measure atmospheric conditions, including the oceans, land, and ice. The goal is to better understand the global dynamics of the atmosphere.
The satellite uses something called a Sea and Land Surface Temperature Radiometer (SLSTR) to measure the energy that radiates back out from Earth’s surface, breaking it into nine separate bands or wavelengths that include visible and infrared light.
It’s the combination of radiometer and color data that creates the red Nile River in the images. In simple terms, the images actually map the heat created by the vegetation that grows along the lush Nile River valley, which emanates in the infrared spectrum, hence creating the red color. This type of data analysis allows scientists to understand the actual state of the vegetation that is being viewed. The SLSTR represents an improvement on previous technology by measuring a wider range and also by delivering images in higher spatial resolutions.
It is anticipated that the near real-time data will be used for forecasting weather and oceanic conditions, among other applications. Images of the land can be used to monitor land use or for tracking wildfires. They can also be analyzed to assess the status of lakes and rivers. The data should also be able to predict oncoming drought conditions by being able to detect the often subtle changes in the color of the vegetation which indicate crop failure before they are noticeable to the naked eye on the ground.
Images from Sentinel-3A complement others taken with its sister satellite Sentinel-2. Sentinel-3A and Sentinel-2 are part of the ESA’s Copernicus program, a multi-dimensional Earth observation system. Sentinel-3A is the third satellite to be launched, adding capabilities for measuring the surface temperature of the land as well as ocean temperatures.
The high-tech imagery recalls ancient legend. As noted in the Times of Israel, the blood red Nile River evokes the biblical story of the the ten plagues visited on Egypt by the god of Israel. According to the biblical story, Aaron was the first priest of Israel, older brother to Moses, who had been adopted by the Pharaoh’s daughter and raised as an Egyptian prince. After years spent out of the country, when Moses returned to Egypt he joined Aaron in asking the Pharaoh to set the Israelites free from their position of slavery.
At first the Pharaoh refused. When Pharaoh persisted, Aaron warned him that the god of Israel would punish him and the people of Egypt by visiting a series of ten plagues upon the country. The first of these occurred when Moses and Aaron went to the banks of the Nile. When Aaron struck the water with his staff (or stick,) the Nile River ran red with blood.
[Image via ESA]