chromosphere tagged posts

Researchers Solve 20-year-old Paradox in Solar Physics

Researchers solve 20-year-old paradox in solar physics
Image of the solar atmosphere showing a coronal mass ejection. Credit: NASA/GSFC/SDO

In 1998, the journal Nature published a seminal letter concluding that a mysterious signal, which had been discovered while analyzing the polarization of sunlight, implies that the solar chromosphere (an important layer of the solar atmosphere) is practically unmagnetised, in sharp contradiction with common wisdom. This paradox motivated laboratory experiments and theoretical investigations, which instead of providing a solution, raised new issues, and even led some scientists to question the quantum theory of matter-radiation interaction.

Researchers at the Istituto Ricerche Solari (IRSOL) in Locarno-Monti (affiliated to USI Università della Svizzera italiana), and the Instituto de Astrofísica de C...

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Magnetic Waves explain Mystery of Sun’s Outer Layer

Image of the sun taken by an instrument on board the Solar Orbiter spacecraft

The Sun’s extremely hot outer layer, the corona, has a very different chemical composition from the cooler inner layers, but the reason for this has puzzled scientists for decades.

One explanation is that, in the middle layer (the chromosphere), magnetic waves exert a force that separates the Sun’s plasma into different components, so that only the ion particles are transported into the corona, while leaving neutral particles behind (thus leading to a build-up of elements such as iron, silicon and magnesium in the outer atmosphere).

Now, in a new study published in The Astrophysical Journal, researchers combined observations from a telescope in New Mexico, the United States, with satellites located near Earth to identify a link between magnetic waves in the chromosphere and area...

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