Washington:
For the first time ever, the magnetic reconnection in space has directly been observed by the scientists. Magnetic reconnection is a fundamental process in nature which may prove to be a key to learn more about the cosmos. This may also be very useful in helping protect the deep space missions far from the Earth in future. The connection between the two sets of magnetic fields gives birth to an explosive reaction. The magnetic fields send particles zooming off in jets when they re-align and snap into a new formation.
The effects of this sudden release of particles and energy - such as giant eruptions on the Sun, the aurora, radiation storms in near-Earth space, high energy cosmic particles that come from other galaxies - have been observed throughout the solar system and beyond.
However, the phenomenon of magnetic reconnection was never witnessed directly. “We developed a mission, the Magnetospheric Multiscale mission (MMS), that for the first time would have the precision needed to gather observations in the heart of magnetic reconnection,” said Jim Burch, principal investigator for MMS at the Southwest Research Institute in US.
“By seeing magnetic reconnection in action, we have observed one of the fundamental forces of nature,” said Branch.
MMS is made of four identical spacecraft that NASA launched in March last year. Flying in a pyramid formation, they create a full 3D map of any phenomena they observe.
The spacecraft travelled through a magnetic reconnection event last year in October at the boundary where Earth’s magnetic field bumps up against the Sun’s magnetic field. In only a few seconds, thousands of observations were collected by the 25 sensors on each of the spacecraft.
This unprecedented time cadence opened the door for scientists to track better than ever before how the magnetic and electric fields changed, as well as the speeds and direction of the various charged particles.
Any set of magnetic fields can be thought of as a row of lines. These field lines are always anchored to some body - a planet, a star - creating a giant magnetic network surrounding it. It is at the boundaries of two such networks where magnetic reconnection happens.
If the two sets of field lines point in opposite directions, the process of realigning is dramatic.“One of the mysteries of magnetic reconnection is why it’s explosive in some cases, steady in others, and in some cases, magnetic reconnection doesn’t occur at all,” said Tom Moore, from the NASA’s Goddard Space Flight Center in US.
The observations show that the electrons shot away in straight lines from the original event at hundreds of miles per second, crossing the magnetic boundaries that would normally deflect them. Once across the boundary, the particles curved back around in response to the new magnetic fields they encountered, making a U-turn.
(With PTI inputs)
