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With its magnetic fields swarming, solar flares erupting, and gigantic columns of material constantly on the move, researchers have always known the sun has a large and extremely active atmosphere.

Now researchers have revealed in fact it stretches for five million miles - far further than previously thought.

Nasa says the results are so stunning they may even have to alter future missions because of the huge protective bubble.

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Scientists used these observations of the sun's atmosphere (the bright light of the sun itself is blocked by the black circle at the middle) from NASA's Solar Terrestrial Relations Observatory on Aug. 5, 2007, to define the outer limits of the solar atmosphere, the corona.

Using NASA's Solar Terrestrial Relations Observatory, scientists have found that this atmosphere, called the corona, is even larger than thought, extending out some 5 million miles above the sun's surface - the equivalent of 12 solar radii.

This information has implications for NASA's upcoming Solar Probe Plus mission, due to launch in 2018 and go closer to the sun than any man-made technology ever has before.

The observations provide the first direct measurements of the inner boundary of the heliosphere -- the giant bubble sparsely filled with solar particles that surrounds the sun and all the planets.

'Combined with measurements from Voyager 1 of the outer boundary of the heliosphere, we have now defined the extent of this entire local bubble,' researchers say.

Scientists used these observations of the sun's atmosphere (the bright light of the sun itself is blocked by the black circle at the middle) from NASA's Solar Terrestrial Relations Observatory on Aug. 5, 2007, to define the outer limits of the solar atmosphere, the corona.

'We've tracked sound-like waves through the outer corona and used these to map the atmosphere,' said Craig DeForest of the Southwest Research Institute in Boulder, Colorado.

The results were published in The Astrophysical Journal on May 12, 2014.

The researchers studied waves known as magnetosonic waves, and they are a hybrid of sound waves and magnetic waves called Alfven waves.

Unlike sound waves on Earth, which oscillate several hundred times per second, these waves oscillate about once every four hours -- and are about 10 times the length of Earth.

Tracking magnetosonic waves showed DeForest and his team that the material throughout this extended space remained connected to the solar material much further in.

That is to say that even out to 5 million miles from the sun, giant solar storms or coronal mass ejections can create ripple effects felt through the corona.

A solar flare erupting: researchers have now revealed the full extent of the sun's atmosphere, which stretches for five million miles.

Beyond that boundary, however, solar material streams away in a steady flow called the solar wind -- out there, the material has separated from the star and its movement can't affect the corona.

Realizing that the corona extends much further than previously thought has important consequences for NASA's Solar Probe Plus because the mission will travel to within 4 million miles of the sun.

Scientists knew the mission would be gathering information closer to the sun than ever before, but couldn't be sure it would travel through the corona proper.

Highly processed movies from NASA's Solar Terrestrial Relations Observatory show wave motions moving downward through the solar corona toward the sun.