Origins of the solar wind
NASA mapped the boundary of the sun and the large-scale forces at play both within it and throughout the entire solar system.
The sun and its atmosphere are made of plasma – a mixture of positively and negatively charged particles that have separated at extremely high temperatures – which both carries and travels along magnetic field lines.
But according to a new study, published in The Astrophysical Journal, as plasma moves further into space, the sun begins to lose magnetic control, as the magnetic field strength drops faster than the pressure of the material.
Eventually the solar material begins to act more like a gas than a magnetically structured plasma.
Scientists liken this breakup of the sun’s rays to the way water is shot from a water pistol – the water starts as a smooth unified stream before breaking into smaller and smaller droplets and finally a fine, misty spray.
NASA’s Solar Terrestrial Relations Observatory (STEREO) was critical to this discovery because it managed to capture the transition of charged solar particles from defined rays in the corona – upper atmosphere of the sun – to solar wind for the first time.
To obtain the clip of the solar wind shown in the video above, the scientists used an algorithm to exclude background noise and other light sources, including other stars and space dust.