Nav: Home

Scientists deepen understanding of magnetic fields surrounding Earth and other planets

July 12, 2019

Vast rings of electrically charged particles encircle the Earth and other planets. Now, a team of scientists has completed research into waves that travel through this magnetic, electrically charged environment, known as the magnetosphere, deepening understanding of the region and its interaction with our own planet, and opening up new ways to study other planets across the galaxy.

The scientists, led by Eun-Hwa Kim, physicist at the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL), examined a type of wave that travels through the magnetosphere. These waves, called electromagnetic ion cyclotron (EMIC) waves, reveal the temperature and the density of the plasma particles within the magnetosphere, among other qualities.

"Waves are a kind of signal from the plasma," said Kim, lead author of a paper that reported the findings in JGR Space Physics. "Therefore, the EMIC waves can be used as diagnostic tools to reveal some of the plasma's characteristics."

Kim and researchers from Andrews University in Michigan and Kyung Hee University in South Korea focused their research on mode conversion, the way in which some EMIC waves form. During this process, other waves that compress along the direction they travel from outer space collide with Earth's magnetosphere and trigger the formation of EMIC waves, which then zoom off at a particular angle and polarization -- the direction in which all of the light waves are vibrating.

Using PPPL computers, the scientists performed simulations showing that these mode-converted EMIC waves can propagate through the magnetosphere along magnetic field lines at a normal angle that is less than 90 degrees, in relation to the border of the region with space. Knowing such characteristics enables physicists to identify EMIC waves and gather information about the magnetosphere with limited initial information.

A better understanding of the magnetosphere could provide detailed information about how Earth and other planets interact with their space environment. For instance, the waves could allow scientists to determine the density of elements like helium and oxygen in the magnetosphere, as well as learn more about the flow of charged particles from the sun that produces the aurora borealis.

Moreover, engineers employ waves similar to EMIC waves to aid the heating of plasma in doughnut-shaped magnetic fusion devices known as tokamaks. So, studying the behavior of the waves in the magnetosphere could deepen insight into the creation of fusion energy, which takes place when plasma particles collide to form heavier particles. Scientists around the world seek to replicate fusion on Earth for a virtually inexhaustible supply of power to generate electricity.

Knowledge of EMIC waves could thus provide wide-ranging benefits. "We are really eager to understand the magnetosphere and how it mediates the effect that space weather has on our planet," said Kim. "Being able to use EMIC waves as diagnostics would be very helpful."
This study was made available online in April 2019, with the final online publication on May 17, 2019.

This research was supported by the DOE's Office of Science (Fusion Energy Sciences), the National Science Foundation, and the National Aeronautics and Space Administration.

PPPL, on Princeton University's Forrestal Campus in Plainsboro, N.J., is devoted to creating new knowledge about the physics of plasmas -- ultra-hot, charged gases -- and to developing practical solutions for the creation of fusion energy. The Laboratory is managed by the University for the U.S. Department of Energy's Office of Science, which is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit

DOE/Princeton Plasma Physics Laboratory

Related Planets Articles:

Ultracool dwarf and the 7 planets
Astronomers have found a system of seven Earth-sized planets just 40 light-years away.
ALMA measures size of seeds of planets
Researchers using the Atacama Large Millimeter/submillimeter Array (ALMA), have for the first time, achieved a precise size measurement of small dust particles around a young star through radio-wave polarization.
Origin of minor planets' rings revealed
A team of researchers has clarified the origin of the rings recently discovered around two minor planets known as centaurs, and their results suggest the existence of rings around other centaurs.
Are planets setting the sun's pace?
The sun's activity is determined by the sun's magnetic field.
A better way to learn if alien planets have the right stuff
A new method for analyzing the chemical composition of stars may help scientists winnow the search for Earth 2.0.
A new Goldilocks for habitable planets
The search for habitable, alien worlds needs to make room for a second 'Goldilocks,' according to a Yale University researcher.
Probing giant planets' dark hydrogen
Hydrogen is the most-abundant element in the universe, but there is still so much we have to learn about it.
Universe's first life might have been born on carbon planets
Our Earth consists of silicate rocks and an iron core with a thin veneer of water and life.
Number of habitable planets could be limited by stifling atmospheres
New research has revealed that fewer than predicted planets may be capable of harbouring life because their atmospheres keep them too hot.
Footprints of baby planets in a gas disk
A new analysis of the ALMA data for a young star HL Tauri provides yet more firm evidence of baby planets around the star.

Related Planets Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Digital Manipulation
Technology has reshaped our lives in amazing ways. But at what cost? This hour, TED speakers reveal how what we see, read, believe — even how we vote — can be manipulated by the technology we use. Guests include journalist Carole Cadwalladr, consumer advocate Finn Myrstad, writer and marketing professor Scott Galloway, behavioral designer Nir Eyal, and computer graphics researcher Doug Roble.
Now Playing: Science for the People

#529 Do You Really Want to Find Out Who's Your Daddy?
At least some of you by now have probably spit into a tube and mailed it off to find out who your closest relatives are, where you might be from, and what terrible diseases might await you. But what exactly did you find out? And what did you give away? In this live panel at Awesome Con we bring in science writer Tina Saey to talk about all her DNA testing, and bioethicist Debra Mathews, to determine whether Tina should have done it at all. Related links: What FamilyTreeDNA sharing genetic data with police means for you Crime solvers embraced...