Data from the four satellites of the MMS mission reveal the dance of electrons in space

Data from the four satellites of the MMS mission reveal the dance of electrons in space
You can’t see them, but swarms of electrons are buzzing through the magnetic environment — the magnetosphere — around Earth. The electrons spiral and dive around the planet in a complex dance dictated by the magnetic and electric fields. When they penetrate into the magnetosphere close enough to Earth, the high-energy electrons can damage satellites in orbit and trigger auroras. Scientists with NASA’s Magnetospheric Multiscale, or MMS, mission study the electrons’ dynamics to better understand their behavior. A new study, published in Journal of Geophysical Research revealed a bizarre new type of motion exhibited by these electrons.

Electrons in a strong magnetic field usually exhibit a simple behavior: They spin tight spirals along the magnetic field. In a weaker field region, where the direction of the magnetic field reverses, the electrons go free style — bouncing and wagging back and forth in a type of movement called Speiser motion. New MMS results show for the first time what happens in an intermediate strength field. Then these electrons dance a hybrid, meandering motion — spiraling and bouncing about before being ejected from the region. This motion takes away some of the field’s energy and it plays a key role in magnetic reconnection, a dynamic process, which can explosively release large amounts of stored magnetic energy.

Read the article:
http://onlinelibrary.wiley.com/doi/10.1002/2017JA024004/full

Source:
https://www.nasa.gov/feature/goddard/2017/nasa-mission-uncovers-dance-of-electrons-in-space

Gif: With no guide field to confine them, electrons (yellow) wiggle back in forth. The electron’s increasing speed is shown by warmer color tracks.
Credits: NASA’s Goddard Space Flight Center/Tom Bridgman

#physics #NASA #MMS #magnetosphere #electrons #space #science #research