Alfvén waves tagged posts

NASA’s Parker Solar Probe (PSP) has flown close enough to the sun to detect the fine structure of the solar wind close to where it is generated at the sun’s surface, revealing details that are lost as the wind exits the corona as a uniform blast of charged particles.

It’s like seeing jets of water emanating from a showerhead through the blast of water hitting you in the face.

In a paper to be published in the journal Nature, a team of scientists led by Stuart D...

Why the sun’s corona reaches temperatures of several million degrees Celsius is one of the great mysteries of solar physics. A “hot” trail to explain this effect leads to a region of the solar atmosphere just below the corona, where sound waves and certain plasma waves travel at the same speed...

The spectacularly colorful aurora borealis — or northern lights — that fills the sky in high-latitude regions has fascinated people for thousands of years. Now, a team of scientists has resolved one of the final mysteries surrounding its origin.

Scientists know that electrons and other energized particles that emanate from the sun as part of the “solar wind” speed down Earth’s magnetic field lines and into the upper atmosphere, where they collide with oxygen and nitrogen molecules, kicking them into an excited state. These molecules then relax by emitting light, producing the beautiful green and red hues of the aurora.

What has not been well understood is precisely how group...

Researchers have confirmed the existence of magnetic plasma waves, known as Alfvén waves, in the Sun’s photosphere. The study, published in Nature Astronomy, provides new insights into these fascinating waves that were first discovered by the Nobel Prize winning scientist Hannes Alfvén in 1947.

The vast potential of these waves resides in their ability to transport energy and information over very large distances due to their purely magnetic nature. The direct discovery of these waves in the solar photosphere, the lowest layer of the solar atmosphere, is the first step towards exploiting the properties of these magnetic waves.

The ability for Alfvén waves to carry energy is also of interest for solar and plasma-astrophysics as it could help explain the extreme heating of the s...