Magnetic Reconnection, the heart of Space Weather.
This is an EXCELLENT article on defining how the sun works, and how magnetic fields – that are literally invisible – can now be seen…in a way. Magnetic reconnection is a very important process in the universe, and yet the ‘force’ of it, the magnetic component, is invisible. All this is absolutely amazing.
The Heart of Space Weather Observed in Action
Two NASA spacecraft have provided the most comprehensive movie ever of a mysterious process at the heart of all explosions on the sun: magnetic reconnection. Magnetic reconnection happens when magnetic field lines come together, break apart and then exchange partners, snapping into new positions and releasing a jolt of magnetic energy.
This process lies at the heart of giant explosions on the sun, such as solar flares and coronal mass ejections, which can fling radiation and particles across the solar system…
…One reason why it’s so hard to study is that magnetic reconnection can’t be witnessed directly, because magnetic fields are invisible…
…”The community is still trying to understand how magnetic reconnection causes flares,” said Yang Su, a solar scientist at the University of Graz in Austria. “We have so many pieces of evidence, but the picture is not yet complete.”…
…Magnetic field lines, themselves, are indeed invisible, but they naturally force charged particles – the material, called plasma, which makes up the sun – to course along their length…
…Below the surface of the sun, the charged material, the plasma, is flowing. Magnetic loops emerge from this flow and set up areas of positive magnetic poles lying next to negative ones.
The loops arc up over the sun from one polarity to the other. As the sun’s material continues to flow under the surface, the positive and negative poles slip past each other – not unlike tectonic plates on Earth slipping past each other – though on the sun, of course, the material is a hot gas, not hard rock.
This causes the arcs above to grow, twist sideways and become more unstable. The very act of that slippage, or shear, puts more energy into the system, coiled and waiting to spring, like twisting up a rubber band before letting it loose. Eventually the magnetic field lines in the arcs buckle inward, touch and reconnect, while giving off a bright flash as the energy releases, sending radiation and energetic particles out into space.
Cluster hears the heartbeat of magnetic reconnection