NASA Spacecraft Discovers New Magnetic Process in Turbulent Space
- 6 years ago
Though close to home, the space immediately around Earth is full of hidden secrets and invisible processes. In a new discovery reported in the journal Nature, scientists working with NASA’s Magnetospheric Multiscale spacecraft — MMS — have uncovered a new type of magnetic event in our near-Earth environment by using an innovative technique to squeeze extra information out of the data.
Magnetic reconnection is one of the most important processes in the space — filled with charged particles known as plasma — around Earth. This fundamental process dissipates magnetic energy and propels charged particles, both of which contribute to a dynamic space weather system that scientists want to better understand, and even someday predict, as we do terrestrial weather. Reconnection occurs when crossed magnetic field lines snap, explosively flinging away nearby particles at high speeds. The new discovery found reconnection where it has never been seen before — in turbulent plasma.
In a new discovery reported in the journal Nature, scientists working with NASA’s Magnetospheric Multiscale spacecraft — MMS — uncovered a new type of magnetic event in our near-Earth environment.
“In the plasma universe, there are two important phenomena: magnetic reconnection and turbulence,” said Tai Phan, a senior fellow at the University of California, Berkeley, and lead author on the paper. “This discovery bridges these two processes.”
Magnetic reconnection has been observed innumerable times in the magnetosphere — the magnetic environment around Earth — but usually under calm conditions. The new event occurred in a region called the magnetosheath, just outside the outer boundary of the magnetosphere, where the solar wind is extremely turbulent. Previously, scientists didn’t know if reconnection even could occur there, as the plasma is highly chaotic in that region. MMS found it does, but on scales much smaller than previous spacecraft could probe.
In a turbulent magnetic environment, magnetic field lines become scrambled. As the field lines cross, intense electric currents (shown here as bright regions) form and eventually trigger magnetic reconnection (indicated by a flash), which is an explosive event that releases magnetic energy accumulated in the current layers and ejects high-speed bi-directional jets of electrons. NASA’s Magnetospheric Multiscale mission witnessed this process in action as it flew through the electron jets the turbulent boundary just at the edge of Earth’s magnetic environment.
MMS uses four identical spacecraft flying in a pyramid formation to study magnetic reconnection around Earth in three dimensions. Because the spacecraft fly incredibly close together — at an average separation of just four-and-a-half miles, they hold the record for closest separation of any multi-spacecraft formation — they are able to observe phenomena no one has seen before.
Magnetic reconnection is one of the most important processes in the space — filled with charged particles known as plasma — around Earth. This fundamental process dissipates magnetic energy and propels charged particles, both of which contribute to a dynamic space weather system that scientists want to better understand, and even someday predict, as we do terrestrial weather. Reconnection occurs when crossed magnetic field lines snap, explosively flinging away nearby particles at high speeds. The new discovery found reconnection where it has never been seen before — in turbulent plasma.
In a new discovery reported in the journal Nature, scientists working with NASA’s Magnetospheric Multiscale spacecraft — MMS — uncovered a new type of magnetic event in our near-Earth environment.
“In the plasma universe, there are two important phenomena: magnetic reconnection and turbulence,” said Tai Phan, a senior fellow at the University of California, Berkeley, and lead author on the paper. “This discovery bridges these two processes.”
Magnetic reconnection has been observed innumerable times in the magnetosphere — the magnetic environment around Earth — but usually under calm conditions. The new event occurred in a region called the magnetosheath, just outside the outer boundary of the magnetosphere, where the solar wind is extremely turbulent. Previously, scientists didn’t know if reconnection even could occur there, as the plasma is highly chaotic in that region. MMS found it does, but on scales much smaller than previous spacecraft could probe.
In a turbulent magnetic environment, magnetic field lines become scrambled. As the field lines cross, intense electric currents (shown here as bright regions) form and eventually trigger magnetic reconnection (indicated by a flash), which is an explosive event that releases magnetic energy accumulated in the current layers and ejects high-speed bi-directional jets of electrons. NASA’s Magnetospheric Multiscale mission witnessed this process in action as it flew through the electron jets the turbulent boundary just at the edge of Earth’s magnetic environment.
MMS uses four identical spacecraft flying in a pyramid formation to study magnetic reconnection around Earth in three dimensions. Because the spacecraft fly incredibly close together — at an average separation of just four-and-a-half miles, they hold the record for closest separation of any multi-spacecraft formation — they are able to observe phenomena no one has seen before.