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Why the sun's magnetic field is still a mystery

Scientists know a lot about the sun, but the forces behind the star's magnetic field remain a mystery.

A new model from NASA shows the strange, swirling lines of plasma being shot around the sun鈥檚 magnetic field.聽

The images and videos are hypnotizing, showing superhot plasma looping and twirling around the giant star. The plasma lines, also called coronal loops, reach from the sun鈥檚 interior to the solar atmosphere, or the corona.聽聽

And while scientists know the sun鈥檚 magnetic field exists, they are still clueless as to what drives the sun鈥檚 magnetic field.聽

鈥淲e鈥檙e not sure exactly where in the sun ,鈥 Dean Pesnell, a space scientist at NASA鈥檚 Goddard Space Flight Center in Maryland, says in a press release. 鈥淚t could be close to the solar surface or deep inside the sun 鈥 or over a wide range of depths.鈥澛

And scientists are racing to understand the sun鈥檚 magnetic field because they do know that the magnetism is responsible for triggering plasma flows and coronal mass ejections, which can affect astronauts in space and even people on Earth.

鈥淕etting a handle on what drives that magnetic system is crucial for understanding the nature of space throughout the solar system: The sun鈥檚 magnetic field is responsible for everything from the solar explosions that cause space weather on Earth 鈥 such as auroras 鈥 to the interplanetary magnetic field and radiation through which our spacecraft journeying around the solar system must travel,鈥 says NASA in a press release.聽

These side effects of magnetism are important to understand because they can damage radio signals among space satellites, causing power blackouts on the ground.聽

Such a solar explosion happened on March 13, 1989, which caused . On March 10, magnetic forces on the sun released a storm cloud of gas that came rushing toward Earth at a million miles per hour. When the electric gas cloud struck Earth鈥檚 magnetic field, it created electrical currents underground, taking down Quebec鈥檚 power grid.聽

But despite the potential powerful impacts from the sun鈥檚 magnetic field, scientists are still confused about the Earth鈥檚 host star.

鈥淭o understand the hows and whys behind the solar cycle, the energetic processes that drive powerful flares in the corona and their impacts on Earth, we must understand how the sun鈥檚 magnetism is generated in the first place,鈥 . 鈥淎nd as it turns out, our knowledge in this area is a little sketchy.鈥

And to further complicate scientists鈥 studies, the magnetic field is constantly changing.聽

Scientists have recognized an 11-year cycle of the sun鈥檚 behavior. Pressure and chaos slowly builds within the sun鈥檚 interior over an 11-year period, with the end of the cycle 鈥 called a solar maximum 鈥 witnessing the most activity. Solar maximums include the greatest number of solar flares and eruptions. 聽

鈥淎t solar maximum, the magnetic field has a very complicated shape with lots of small structures throughout 鈥 ,鈥 said Dr. Pesnell. 鈥淎t solar minimum, the field is weaker and concentrated at the poles. It鈥檚 a very smooth structure that doesn鈥檛 form sunspots.鈥

Understanding the sun's magnetic field at the solar maximum is especially important, say scientists, because these years render the powerful solar flares that can trigger Quebec-like blackouts.

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