An astronaut aboard the International Space Station photographed a fiery sunset that looks like a vast sheet of flame. With Earth’s surface already in darkness, the setting sun, cloud masses, and sideways viewing angle make a powerful image of the kind that astronauts use to commemorate their flights.
Thin layers of lighter and darker blues reveal the many layers of the atmosphere. The lowest layer – the orange-brown line with clouds and dust and smoke – is known to scientists as the troposphere, the layer of weather as we experience it.
Astronauts see the atmosphere like this roughly every 90 minutes, as they view sixteen sunrises and sixteen sunsets every day. Astronauts often comment on how thin and fragile Earth’s atmosphere seems.
The smoke and particles of dust in the atmosphere give the strong red color to sunsets.
In this photo, the astronaut was looking directly toward one of the dustiest parts of the southern hemisphere, where consistently strong winds blow dust from the arid Patagonian deserts of South America out into the ocean. From the space station’s altitude of 400 kilometers (250 miles), astronauts can see more than 2,000 kilometers to the horizon.
That let the astronaut catch this view that goes most of the way to the dust source, and the fiery sunset, even though the space station was half way between South America and South Africa.