Magnetic

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LEVITATING PUMPKINS!

“And the cursed pumpkin rose up from the earth, carried to the sky by the spirits of All Hallows’ Eve.” Or in other words, Andy put a superconductor in a pumpkin and levitated it on a magnetic track.

Happy Halloween! To celebrate this year we thought we’d have some fun with a pumpkin and superconductor. Inspired by our previous video, Andy took to the prep room to imbue a cheerful pumpkin with the eerie powers of superconductor levitation.

Watch the full video here!

Magnetic Wormhole Created in Lab

“Ripped from the pages of a sci-fi novel, physicists have crafted a wormhole that tunnels a magnetic field through space.

“This device can transmit the magnetic field from one point in space to another point, through a path that is magnetically invisible,” said study co-author Jordi Prat-Camps, a doctoral candidate in physics at the Autonomous University of Barcelona in Spain. “From a magnetic point of view, this device acts like a wormhole, as if the magnetic field was transferred through an extra special dimension." 

The idea of a wormhole comes from Albert Einstein’s theories. In 1935, Einstein and colleague Nathan Rosen realized that the general theory of relativity allowed for the existence of bridges that could link two different points in space-time. Theoretically these Einstein-Rosen bridges, or wormholes, could allow something to tunnel instantly between great distances (though the tunnels in this theory are extremely tiny, so ordinarily wouldn’t fit a space traveler). So far, no one has found evidence that space-time wormholes actually exist. 

The new wormhole isn’t a space-time wormhole per se, but is instead a realization of a futuristic "invisibility cloak” first proposed in 2007 in the journal Physical Review Letters. This type of wormhole would hide electromagnetic waves from view from the outside. The trouble was, to make the method work for light required materials that are extremely impractical and difficult to work with, Prat said.

But it turned out the materials to make a magnetic wormhole already exist and are much simpler to come by. In particular, superconductors, which can carry high levels of current, or charged particles, expel magnetic field lines from their interiors, essentially bending or distorting these lines. This essentially allows the magnetic field to do something different from its surrounding 3D environment, which is the first step in concealing the disturbance in a magnetic field.So the team designed a three-layer object, consisting of two concentric spheres with an interior spiral-cylinder. The interior layer essentially transmitted a magnetic field from one end to the other, while the other two layers acted to conceal the field’s existence.”

Exploring the Invisible: Magnetic Reconnection

People always say that space is a vacuum. That’s true – space is about a thousand times emptier than even the best laboratory vacuums on Earth. Even so, space contains lots of stuff we can’t see. We study this invisible space stuff because we need to understand it to safely send technology and astronauts into space.

The stuff that fills space is mostly plasma, which is gas where particles have separated into positive ions and negative electrons, creating a sea of electrically-charged particles. This plasma also contains something else – magnetic fields.

The particles in space can reach very high speeds, creating radiation. One of the main engines that drives that acceleration to high speeds is called magnetic reconnection. But what is magnetic reconnection?

Magnetic reconnection happens when two oppositely-aligned magnetic fields pinch together and explosively realign. As the lines snap into their new configuration – as in the animation below – the sudden change sends electrons and ions flying at incredible speeds.

Magnetic reconnection releases energy. We can’t see the energy itself, but we can see the results: It can set off solar explosions – such as solar flares and coronal mass ejections – or disturbances near Earth that cause auroras.

In March 2015, we launched the four Magnetospheric Multiscale, or MMS, spacecraft on a mission to study magnetic reconnection. Magnetic reconnection only happens in a vacuum with ionized gas. These conditions are vanishingly rare on Earth, so we went to space to study this explosive process.

Because MMS has four separate – but essentially identical – spacecraft, it can watch magnetic reconnection in three dimensions.

The below animation shows what MMS sees – the magnetic fields are magenta, positive ions are purple, and electrons are yellow. The arrows show which the direction the fields and particles are moving.

Like how a research plane flies through a hurricane, MMS flew directly through a magnetic reconnection event in October 2015.

In the data visualization below, you can see the magnetic reconnection happening as the yellow arrows (which represent electrons) explode in all directions. You’ll notice that the magnetic field (represented by magenta arrows) changes direction after the magnetic reconnection, showing that the magnetic field has reconfigured.

Magnetic reconnection transfers energy into Earth’s atmosphere – but it’s not inherently dangerous. Sometimes, the changes in Earth’s magnetic field caused by magnetic reconnection can create electric currents that put a strain on power systems. However, the energy released is more often channeled into auroras, the multicolored lights that most often appear near the North and South Poles.

As the MMS mission continues the four spacecraft can be moved closer together or farther apart, letting us measure magnetic reconnection on all different scales. Each set of observations contributes to explaining different aspects of this invisible phenomenon of magnetic reconnection. Together, the information will help scientists better map out our space environment — crucial information as we journey ever farther beyond our home planet.

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