The edge of the solar system is filled with a turbulent sea of magnetic bubbles, astronomers said Thursday.

The finding changes ideas about the distant region and how the rest of the galaxy interacts with the solar system.

The two Voyager spacecraft, which have spent more than three decades travelling toward the outer boundaries of our solar system, found unexpected changes in the magnetic field that extends outward from the Sun. This discovery was made once they reached the heliosheath, as the outer part of the solar system is called.

The long sausage-shaped magnetic bubbles are approximately 160 million kilometres wide. A computer model was used to crunch data from the spacecraft to postulate their existence, as they cannot be seen with the eye.

They make the area very turbulent, “just like the bubbliest parts of your jacuzzi,” said University of Maryland astronomer James Drake.

The finding means that damaging galactic cosmic rays entering the solar system from the rest of the galaxy must first pass through the sea of bubbles, causing them to bounce around like inside a pinball machine before finally entering the solar system.

Scientists have long measured the rays, which can have damaging health effects for astronauts, but this could change theories about the rays and how they reach us from interstellar space.

Voyager 1 and Voyager 2 reached the heliosheath in the past decade and are still travelling through it.

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