Science & Tech · Science & Environment · 4 hrs ago
Parker Solar Probe finds paired twists in the solar wind
Scientists found an organized pattern in the solar wind’s magnetic field, which had often seemed random.
The team studied readings from NASA’s Parker Solar Probe, collected between September and November 2021 as the spacecraft moved at different distances from the sun.
The probe detected two opposite twists: one at 10 ripples a second and another at 20.
The direction of a magnetic field’s twist is called helicity, and seeing the two twists together is known as a bihelical structure.
Both twists shifted to slower frequencies farther from the sun, meaning the structures grew larger, but the shift was faster than simple gas expansion would predict.
The findings point to interactions across different scales, rather than local conditions alone, as a possible driver of how the magnetic pattern changes.
NASA’s Parker Solar Probe detected two opposite twists in the solar wind’s magnetic field at different ripple sizes.
The pattern appeared near the point where the gas stops behaving like a fluid and begins behaving like separate particles.
One twist appeared at 10 ripples per second and the other at 20 ripples per second.
The researchers found that both patterns shifted toward slower frequencies as the solar wind traveled outward, faster than simple expansion would predict.
The findings suggest that interactions across different scales may drive the changes.
- Who
- A team led by Masatomi Iizawa of TU Braunschweig, with Nobumitsu Yokoi of the University of Tokyo and colleagues in ten countries.
- What
- Parker Solar Probe measurements revealed paired magnetic twists in the solar wind. The patterns shifted as the wind traveled outward.
- When
- The team analyzed measurements from late September to late November 2021.
- Where
- In the solar wind, as Parker Solar Probe moved between 0.1 and 0.78 times the Earth-sun distance.
- Why
- The researchers investigated magnetic-field patterns in turbulent solar wind and how those patterns change with distance.
This story does not have two clearly opposing sides.
Parker Solar Probe collected the magnetometer readings analyzed by the team, sampling one hour at a time.
The magnetic-field spectrum showed peaks at 10 and 20 ripples per second, with opposite twists.
Both peaks shifted toward slower frequencies, corresponding to larger structures.
- Probe
- NASA’s Parker Solar Probe
- Measurement period
- Late September to late November 2021
- Probe distance
- 0.1 to 0.78 times the Earth-sun distance
- First peak
- 10 ripples per second
- Second peak
- 20 ripples per second; opposite twist from the first
What people are saying
We see a clear structure in the spectrum, even though the turbulence represents unstructured motions