There is much that we don’t know about our own planet and our atmosphere. Scientists strive to learn more as a way to not only understand our own planet, but to be able to apply this understanding to planets outside our solar system in a search for life.
Scientists have discovered something new in the Earth's atmosphere described as a warm cloak of plasma. The feature is part of the Earth's magnetosphere that is key to protecting the planet from solar wind and radiation. The only visible parts of the Earth's magnetosphere are the aurora borealis and the aurora australis. While most people don’t think much about the magnetosphere, it can have an effect on our lives.
Professor of Physics Rick Chappell from Vanderbilt University told Space.com, "Although it is invisible, the magnetosphere has an impact on our everyday lives. For example, solar storms agitate the magnetosphere in ways that can induce power surges in the electrical grid that trigger black outs, interfere with radio transmissions and mess up GPS signals. Charged particles in the magnetosphere can also damage the electronics in satellites and affect the temperature and motion of the upper atmosphere."
The new region was discovered after Chappell and other researchers pieced together what they call a "natural cycle of energization" that accelerates low-energy ions in the Earth's atmosphere into the higher energy levels found in regions of the magnetosphere.
The warm plasma cloak starts on the night side of the planet and wraps around the dayside according to the researchers. As the cloak reaches the afternoon side of the planet, it gradually fades away. Due to that fact the cloak only surrounds about 3/4 of the planet.
The cloak is fed by the low-energy particles lifted into space over the Earth's poles, carried behind the Earth on its magnetic tail, and then turned 180 degrees by a kink in the magnetic field. The particles are then boosted back towards the Earth into the region called the plasma sheet.
A key part of the analysis that led to the discovery was a program developed by Dominique Delcourt, a researcher from France. Delcourt developed a program that predicted where particles in the atmosphere go. One of the predictions made by the software was how ions moved and ultimately ended up in the warm plasma cloak.
Chappell told Space.com, "These motions are very complicated. Ions spiral around in the magnetic field. They bounce and drift. A lot of things can happen, but Dominic developed a mathematical code that can predict where they go."
He continued, "We have recognized all the other regions for a long time, but the plasma cloak was a fuzzy thing in the background which we didn't have enough information about to make it stand out. When we got enough pieces, there it (warm plasma cloak) was!"
Chappell and his colleges used observations of satellites to measure the properties of ions in different locations of the magnetosphere. When these observations were applied to the computer code designed by Delcourt the discovery of the warm plasma cloak was made.
