It looks like something out of a magic show, where the magician is able to defy gravity and float or levitate an object in midair with no apparent explanation. Check out this really cool video which is not a Vegas show, but an example of something called quantum levitation:
It’s not magic at all, but a very cool demonstration from the Association of Science-Technology Centers. It’s a demo from Tel-Aviv University on what happens when a superconductor gets trapped in a magnetic field. What you’re witnessing is something similar to the Meissner Effect.
A disk of very thin sapphire, coated by a material called yttrium barium copper oxide (YBa2Cu3O7-x, to be exact) gets thrown into a bath of liquid nitrogen to bring it to negative 300 degrees Fahrenheit. This creates a superconductor, or an object that conducts electricity without resistance and no energy loss. (I wish my air conditioner could have pulled that off this summer).
A row of magnets is added, and the disc seems to float or be trapped by the magnetic field. The combination of magnetism and superconductivity create the levitation. According to the university’s website, the two fields "don’t like each other." The two fields repel each other, much like putting the opposite ends of a magnet together.
In this case, however, some of the magnetic field does penetrate though and creates something called a flux tube. These tubes move, and the superconductor tries to stop that so the conductor looks as if it is locked in midair.
Don't plan on jumping on the "quantum levitation train" to shorten your daily commute any time soon. Until scientists can figure out a way to have a superconductor at a temperature other than negative 300, the idea is not yet practical. Maybe someday... Stay tuned.
Blue stragglers are stars that are observed to be brighter and bluer than we Earthlings would expect, since these characteristics make the stars appear younger than they actually are.
No one's been able to pin down how blue stragglers form. But a group of scientists report a theory in this week's issue of the journal Nature based on new observations.
"All six Pratt Whitney Rocketdyne space shuttle main engines from Endeavour's STS-134 and Atlantis' STS-135 missions sit in test cells inside the Engine Shop at NASA's Kennedy Space Center in Florida. For the first time, all 15 shuttle main engines are in the shop at the same time, being prepped for shipment to NASA's Stennis Space Center in Mississippi, where they are being repurposed for use on NASA's next generation heavy lift rocket, the Space Launch System."Source: NASA
Through the use of microwaves, MIT researchers have devised technology to see through walls in real time.
The radar array system, created by Gregory Charvat and John Peabody at the university's Lincoln Laboratory, sends microwave signals that bounce off objects and ultimately return radar images to a screen. The waves can even penetrate concrete walls.
Charvat said Tuesday that the project has been in the works for a while.
“It originally started out as my dissertation, where I developed a very slow prototype,” he said. “When I moved to Lincoln Lab, I teamed up with another colleague (Peabody) who was working with technology used for imaging human tissue” in medical environments such as hospitals.