Further From The Sun, The Hotter it Gets

The fact that things don't always follow apparent common sense is one of the strange things about space. Consider the sun as an example. Since the surface is closer to the nuclear furnace at the sun's core, one would assume that it would be hotter than the outer atmosphere.

The sun doesn't operate that way, which is the issue. The solar surface, also known as the photosphere, has a temperature that ranges from 6,700 to 11,000 degrees Fahrenheit (3,700 to 6,200 degrees Celsius). However, the atmosphere seems to get hotter the further away you are from the sun's surface. The temperature in the corona, the outermost layer of the atmosphere, surges to an incredible 900,000 degrees Fahrenheit at a distance of around 1,200 miles (2,100 kilometers) from the surface (500,000 degrees Celsius).

Along with the sun, several other stars display this peculiar pattern, and for a very long time, astronomers were baffled as to why. They came up with the theory that magneto hydrodynamic (MHD) waves transport energy directly from below the photosphere to the corona, much like an express train that makes no stops along the way.

In 2013, British researchers explored the chromosphere, the region between the photosphere and the corona, as well as the MHD waves, using advancements in imaging technology. Their calculations showed that the corona might be heated and that energy could be transported there by waves.