I’m Never Gonna Finish This Meme

Spacewalk Recap Told in GIFs

Friday, Oct. 20, NASA astronauts Randy Bresnik and Joe Acaba ventured outside the International Space Station for a 6 hour and 49 minute spacewalk. Just like you make improvements to your home on Earth, astronauts living in space periodically go outside the space station to make updates on their orbiting home.

During this spacewalk, they did a lot! Here’s a recap of their day told in GIFs…

All spacewalks begin inside the space station. Astronauts Paolo Nespoli and Mark Vande Hei helped each spacewalker put on their suit, known as an Extravehicular Mobility Unit (EMU).

They then enter an airlock and regulate the pressure so that they can enter the vacuum of space safely. If they did not regulate the pressure safely, the astronauts could experience something referred to as “the bends” – similar to scuba divers.

Once the two astronauts exited the airlock and were outside the space station, they went to their respective work stations.

Bresnik replaced a failed fuse on the end of the Dextre robotic arm extension, which helps capture visiting vehicles.

During that time, Acaba set up a portable foot restraint to help him get in the right position to install a new camera.

While he was getting set up, he realized that there was unexpected wearing on one of his safety tethers. Astronauts have multiple safety mechanisms for spacewalking, including a “jet pack” on their spacesuit. That way, in the unlikely instance they become untethered from the station, the are able to propel back to safety.

Bresnik was a great teammate and brought Acaba a spare safety tether to use.

Once Acaba secured himself in the foot restraint that was attached to the end of the station’s robotic arm, he was maneuvered into place to install a new HD camera. Who was moving the arm? Astronauts inside the station were carefully moving it into place!

And, ta da! Below you can see one of the first views from the new enhanced HD camera…(sorry, not a GIF).

After Acaba installed the new HD camera, he repaired the camera system on the end of the robotic arm’s hand. This ensures that the hand can see the vehicles that it’s capturing.

Bresnik, completed all of his planned tasks and moved on to a few “get ahead” tasks. He first started removing extra thermal insulation straps around some spare pumps. This will allow easier access to these spare parts if and when they’re needed in the future.

He then worked to install a new handle on the outside of space station. That’s a space drill in the above GIF. 

After Acaba finished working on the robotic arm’s camera, he began greasing bearings on the new latching end effector (the arm’s “hand”), which was just installed on Oct. 5.

The duo completed all planned spacewalk tasks, cleaned up their work stations and headed back to the station’s airlock. 

Once safely inside the airlock and pressure was restored to the proper levels, the duo was greeted by the crew onboard. 

They took images of their spacesuits to document any possible tears, rips or stains, and took them off. 

Coverage ended at 2:36 p.m. EDT after 6 hours and 49 minutes. We hope the pair was able to grab some dinner and take a break!

You can watch the entire spacewalk HERE, or follow @Space_Station on Twitter and Instagram for regular updates on the orbiting laboratory. 

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

Theodore Isaac Rubin, American Psychiatrist (via books-n-quotes)

Have you considered that if you don’t make waves, nobody including yourself will know that you are alive?

Spinal Stimulators Repurposed to Restore Touch in Lost Limb

Imagine tying your shoes or taking a sip of coffee or cracking an egg but without any feeling in your hand. That’s life for users of even the most advanced prosthetic arms.

Although it’s possible to simulate touch by stimulating the remaining nerves in the stump after an amputation, such a surgery is highly complex and individualized. But according to a new study from the University of Pittsburgh’s Rehab Neural Engineering Labs, spinal cord stimulators commonly used to relieve chronic pain could provide a straightforward and universal method for adding sensory feedback to a prosthetic arm.

For this study, published in eLife, four amputees received spinal stimulators, which, when turned on, create the illusion of sensations in the missing arm.

“What’s unique about this work is that we’re using devices that are already implanted in 50,000 people a year for pain — physicians in every major medical center across the country know how to do these surgical procedures — and we get similar results to highly specialized devices and procedures,” said study senior author Lee Fisher, Ph.D., assistant professor of physical medicine and rehabilitation, University of Pittsburgh School of Medicine. 

The strings of implanted spinal electrodes, which Fisher describes as about the size and shape of “fat spaghetti noodles,” run along the spinal cord, where they sit slightly to one side, atop the same nerve roots that would normally transmit sensations from the arm. Since it’s a spinal cord implant, even a person with a shoulder-level amputation can use this device 

Fisher’s team sent electrical pulses through different spots in the implanted electrodes, one at a time, while participants used a tablet to report what they were feeling and where.

All the participants experienced sensations somewhere on their missing arm or hand, and they indicated the extent of the area affected by drawing on a blank human form. Three participants reported feelings localized to a single finger or part of the palm.

“I was pretty surprised at how small the area of these sensations were that people were reporting,” Fisher said. “That’s important because we want to generate sensations only where the prosthetic limb is making contact with objects.”

When asked to describe not just where but how the stimulation felt, all four participants reported feeling natural sensations, such as touch and pressure, though these feelings often were mixed with decidedly artificial sensations, such as tingling, buzzing or prickling.

Although some degree of electrode migration is inevitable in the first few days after the leads are implanted, Fisher’s team found that the electrodes, and the sensations they generated, mostly stayed put across the month-long duration of the experiment. That’s important for the ultimate goal of creating a prosthetic arm that provides sensory feedback to the user. 

“Stability of these devices is really critical,” Fisher said. “If the electrodes are moving around, that’s going to change what a person feels when we stimulate.” 

The next big challenges are to design spinal stimulators that can be fully implanted rather than connecting to a stimulator outside the body and to demonstrate that the sensory feedback can help to improve the control of a prosthetic hand during functional tasks like tying shoes or holding an egg without accidentally crushing it. Shrinking the size of the contacts — the parts of the electrode where current comes out — is another priority. That might allow users to experience even more localized sensations. 

“Our goal here wasn’t to develop the final device that someone would use permanently,” Fisher said. “Mostly we wanted to demonstrate the possibility that something like this could work.”

Why can we find geometric shapes in the night sky? How can we know that at least two people in London have exactly the same number of hairs on their head? And why can patterns be found in just about any text — even Vanilla Ice lyrics? Is there a deeper meaning? 

The answer is no, and we know that thanks to a mathematical principle called Ramsey theory. So what is Ramsey theory? Simply put, it states that given enough elements in a set or structure, some particular interesting pattern among them is guaranteed to emerge.

The mathematician T.S. Motzkin once remarked that, “while disorder is more probable in general, complete disorder is impossible.” The sheer size of the Universe guarantees that some of its random elements will fall into specific arrangements, and because we evolved to notice patterns and pick out signals among the noise, we are often tempted to find intentional meaning where there may not be any. So while we may be awed by hidden messages in everything from books, to pieces of toast, to the night sky, their real origin is usually our own minds.

From the TED-Ed Lesson The origin of countless conspiracy theories - PatrickJMT

Animation by Aaron, Sean & Mathias Studios

Packing numerous books and papers that he plans to read over winter break, the grad student deludes himself.

Sainte-Geneviève Library. Paris, France.  

Earlier this fall, I attempted my first corn maze. It didn’t work out very well. Early on I unknowingly cut through an area meant to be impassable and thus ended up missing the majority of the maze. Soap, as it turns out, is a much better maze-solver, taking nary a false turn as it heads inexorably to the exit. The secret to soap’s maze-solving prowess is the Marangoni effect. 

Soap has a lower surface tension than the milk that makes up the maze, which causes an imbalance in the forces at the surface of the liquid. That imbalance causes a flow in the direction of higher surface tension; in other words, it tends to pull the soap molecules in the direction of the highest milk concentration. But that explains why the soap moves, not how it knows the right path to take. It turns out that there’s another factor at work. Balancing gravitational forces and surface tension forces shows that the soap tends to spread toward the path with the largest surface area ahead. That’s the maze exit, so Marangoni forces pull the soap right to the way out! (Video credit: F. Temprano-Coleto et al.)