By Marissa Sura
WVU University Relations/News
Last week a winter weather system pummeled much of the nation, bringing cities to a standstill. In contrast, space weather – which occurs between the sun and Earth – could cause massive electrical grid failure, scrambled GPS signals and the disruption of cellular phone communication around the world.
One of the most important drivers of space weather is something called magnetic reconnection, and it is a mystery astronomers have been trying to understand.
On March 12, NASA will launch the Magnetospheric Multiscale mission, the first such mission dedicated to studying – and it is hoped, solving – this mystery.
Magnetic reconnection is a dynamic phenomenon in which magnetic fields break apart and immediately reconnect to another broken magnetic field then ricochet particles into the space environment. Cassak, a plasma physicist, said a common comparison to the ricocheting process is the snapping of a taut rubber band.
Magnetic reconnection is a fundamental process that occurs in our universe – around the sun and other stars, many planets, black holes, neutron stars and into other galaxies – but what occurs at the point of reconnection is a question that, so far, has gone unanswered.
Historically, magnetic reconnection has been difficult to study due to the scale and speed of the process, Cassak said.
“The MMS mission is an unprecedented opportunity because up to this point, scientists have been plagued with the inability to measure the smallest scales of reconnection,” he said. “We haven’t been able to process data fast enough to determine what is happening at the moment the magnetic fields break and reconnect.”
The perfect storm
Cassak explained that like many things that affect our planet, magnetic reconnection begins with the sun.
From our terrestrial perch, the center of our solar system appears as a radiating orb of warm light.
But up close, the sun reveals a fiery personality.
The star’s surface is violent and chaotic, bubbling with eruptions. The undulating, twisting magnetic fields on the surface rupture, spewing energy in solar flares and coronal mass ejections that travel through our solar system.
These superheated, massive explosions can hurtle billions of tons of solar material toward Earth at spectacular speeds, slamming into Earth’s protective magnetic field, called the magnetosphere.
That interaction causes space weather events such as the ethereal Aurora – the Northern and Southern Lights. It can also produce geomagnetic storms, which can result in scenes much less picturesque.
As a result of solar eruptions, power grids were damaged in Quebec in 1989 and Sweden in 2003. GPS satellites were short circuited as recently as 2010. Cellular phone service can be disrupted, airplanes could need to be rerouted and the safety of astronauts and spacecraft could be at risk.
Cassak and his research group use sophisticated computer models that help scientists understand and predict reconnection, but he said those simulations can only go so far.
“The process of magnetic reconnection is complex. The event occurs at microscopic scales, but its impact is huge,” he explained. “In the magnetosphere, reconnection happens in an area six miles wide, but affects the whole magnetosphere, which is a million miles long.”
Cassak said that through MMS observations researchers will be able for the first time to measure what is going on in that six-mile region. In addition to learning about reconnection in the many places it occurs, it is hoped that the observations will help space weather agencies make more accurate predictions so that necessary preparations can be made.
A mission like no other
No space mission has ever been dedicated to the study of magnetic reconnection and no mission has ever observed it with the high resolution of MMS.
The two-year MMS mission consists of four identical spacecraft that will fly in a pyramid formation as little as six miles apart to two primary locations – one on the day-side of Earth and one on the night-side – allowing researchers to view magnetic reconnection in 3D.
In total, the mission will pack 100 precision instruments in 12,000 pounds of NASA-engineered spacecraft. In space, with sensor booms extended, each MMS spacecraft will be 94 feet tall and 369 feet wide – nearly the size of Fenway Park.
The spacecraft will fly through reconnection regions in a fraction of a second, so the sensors will take measurements 100 times faster than any other mission.
“Imagine watching a football game, but you can only watch one minute at a time and you must wait an hour in between the times that you can watch,” Cassak said. “It would be extremely difficult to figure out what was happening. That is what people studying reconnection have been up against before MMS.”
MMS is scheduled to launch on March 12, aboard a United Launch Alliance Atlas V rocket from Cape Canaveral Air Force Station, Florida.
Cassak and other MMS team members will participate in a NASA Mission Science Briefing on Wed., March 11 at 1 p.m. EDT. He will also participate in the NASA Social on launch day at 3 p.m. EDT, which will be carried live on NASA Television. Information can be found here.
Cassak is available to offer commentary to the media. He can be reached at Paul.Cassak@mail.wvu.edu or 304-293-5102.