March 28, 2024

ELFIN CubeSat Discovers Source of Super-Fast Electron Rain

Electrons in Earths radiation belts, reveal as red and yellow cross-sections, usually spiral back and forth, bouncing in between the Poles. Researchers from the University of California Los Angles (UCLA) observed this rain, known as “electron rainfall,” from low-Earth orbit using the Electron Losses and Fields Investigation, or ELFIN, objective. Similar to a coiled slinky bouncing back and forth in between two hands, electrons in the radiation belts take a trip in spirals in between Earths North and South magnetic poles. Under specific conditions, electro-magnetic vibrations called whistler waves can take place in the radiation belts, speeding and energizing up the electrons so much that they can be lost into the environment, developing the electron rain.
Factoring in the effect of electron losses on the environment is crucial not just for terrestrial modeling, but likewise for understanding Earths magnetic environment and predicting risks to satellites, astronauts, and other area infrastructure.

” ELFIN is the first satellite to determine these super-fast electrons,” stated Xiaojia Zhang, lead author on the brand-new paper and researcher in UCLAs Department of Earth, Planetary, and Space Sciences (EPSS). “The mission is yielding brand-new insights due to its special viewpoint.”
The THEMIS and ELFIN satellites (orbits displayed in cyan and green, respectively) worked together to assist understand the mystery of electron rain. When whistler waves (purple) connect with the electrons, they can provide them additional energy (red spiral), which triggers them to fall under the environment. Credit: Zhang et al. 2022
The near-Earth space environment is extremely vibrant and filled with charged particles orbiting in giant rings around the world called Van Allen radiation belts. Similar to a coiled slinky recuperating and forth in between 2 hands, electrons in the radiation belts take a trip in spirals between Earths North and South magnetic poles. Under certain conditions, electromagnetic vibrations called whistler waves can occur in the radiation belts, speeding and stimulating up the electrons so much that they can be lost into the environment, producing the electron rain.
Integrating THEMIS observations of whistler waves, ELFINs electron information and sophisticated computer system modeling, the group saw how the whistler waves caused a rapid gush of electrons to stream into the atmosphere, far beyond the amount expected from previous theories. Present area weather models do not account for this extra electron flow, which not just adds to amazing auroras, but can damage low-orbiting satellites and affect atmospheric chemistry.
” Its really a fulfilling sensation to have actually increased our knowledge of space science, using data from the hardware we built ourselves,” stated Colin Wilkins, co-author, instrument lead, and space physics doctoral trainee in EPSS. “It takes tremendous effort and decision behind the scenes to make that occur.”
The team even more showed that this type of radiation belt loss to the atmosphere can increase significantly throughout geomagnetic storms, which are disturbances triggered by enhanced solar activity that can impact near-Earth space. Existing models do not represent this, therefore undervaluing the effects of electron rainfall.
Factoring in the impact of electron losses on the atmosphere is crucial not only for terrestrial modeling, but also for comprehending Earths magnetic environment and forecasting threats to satellites, astronauts, and other space facilities. Space is frequently believed to be separate from our upper environment, the 2 are inextricably connected. Understanding how theyre linked can benefit satellites and astronauts going through the region, which are increasingly important for commerce, Earth monitoring, telecoms, and tourist.
” The ELFIN objective has actually given UCLA trainees the opportunity to deal with an industry-caliber task right on campus, and Im happy that weve had the ability to accomplish a lot with over 300 undergraduate students without sacrificing the quality of the science,” said Ethan Tsai, co-author, project manager, and doctoral student in space physics. “Data from the ELFIN satellites are at the cutting edge of area weather condition research studies and will be heavily utilized by researchers around the globe over the next decade, so weve worked very hard to make our data easily available and open to the entire area science neighborhood.”
Recommendation: “Superfast rainfall of energetic electrons in the radiation belts of the Earth” by Xiao-Jia Zhang, Anton Artemyev, Vassilis Angelopoulos, Ethan Tsai, Colin Wilkins, Satoshi Kasahara, Didier Mourenas, Shoichiro Yokota, Kunihiro Keika, Tomoaki Hori, Yoshizumi Miyoshi, Iku Shinohara and Ayako Matsuoka, 25 March 2022, Nature Communications.DOI: 10.1038/ s41467-022-29291-8.

Electrons in Earths radiation belts, show as red and yellow cross-sections, usually spiral backward and forward, bouncing between the Poles. However, disruptions to the belts can increase electrons out of their typical orbits, making them shower down at the North and South Pole, where they can stimulate the auroras. Credit: Emmanuel Masongsong
Using a NASA-funded CubeSat, scientists have discovered a new source of super-fast, energetic electrons drizzling down on our planet, which can have ramifications for space infrastructure and climatic modeling.
Researchers from the University of California Los Angles (UCLA) observed this rain, called “electron rainfall,” from low-Earth orbit using the Electron Losses and Fields Investigation, or ELFIN, mission. ELFIN is a set of little, cube-shaped satellites referred to as CubeSats. It was developed and operated by UCLA undergraduate and graduate trainees under assistance from little group of staff mentors.
Integrating ELFIN information with more distant observations from NASAs Time History of Events and Macroscale Interactions throughout Substorms, or THEMIS, spacecraft, the researchers identified that the electron rain was triggered by whistler waves, a kind of electro-magnetic wave that ripples through plasma in space. Their outcomes, released in Nature Communications, discovered more electron precipitation than leading theories had actually previously predicted.