Author: Chris Higgins

In September 2016, the Bank of England issued a new fiver (£5 note) made from a polymer. The new note replaces paper bills, and is designed to be vastly more sturdy. It’s nearly impossible to tear. So how can we destroy one of these things? With science!

In the video below, the intrepid Brits of Periodic Videos subject the new fiver to a series of tortures. The most straightforward method is freezing the note with liquid nitrogen, then shattering it with a hammer. Beyond that simple method, things get a bit crazy with fuming nitric acid that’s “gone a bit brown.” Enjoy:

As professor Poliakoff says in the video above, it’s legal to destroy these notes—but illegal to scribble on the Queen’s face.

(If you enjoyed that video, there’s 15 minutes of raw footage showing outtakes.)

On April 23, 1967, the Soviet space program launched its first-ever Soyuz spacecraft with a person in it. The flight was plagued with technical problems and ended in tragedy. But 50 years later, we’re still using descendants of the Soyuz to ferry people and supplies to and from space, most notably the International Space Station. The Soyuz rocket is, by far, the most used and most reliable space launch system humans have ever built. Unfortunately the first Soyuz pilot didn’t survive.

Soyuz 1’s pilot was cosmonaut Vladimir Komarov, a Soviet test pilot and engineer who had previous experience in space. His voyage on the mission made him the first Soviet cosmonaut to make a second trip into space. He also became the first person to die on a space mission.

The tragedy of Soyuz 1 started with political pressure. Soviet leaders apparently wanted to celebrate Lenin’s April 22 birthday with the Soyuz launch. They were also keen to beat the Americans to the moon, and the Soyuz program was akin to NASA’s Apollo—aimed at an eventual lunar landing. Apollo was suffering, as the Apollo 1 crew had died that January on the ground in a terrible fire. If the Soviets could get Soyuz running, it would be a massive leap. Despite many technical setbacks on the ground, Soviet leaders pushed for Soyuz 1 to launch.

While cosmonaut Yuri Gagarin (the first human in orbit) was listed as Komarov’s backup pilot, there was no way Soviet leaders would allow a national treasure to risk his life in space again. So in a practical sense, either Komarov launched or the mission would be scrubbed. He launched from Baikonur Cosmodrome just after midnight UTC (just after 3:30am Moscow time).

The problems started early. One of the Soyuz craft’s two solar panels failed to deploy, leaving the vessel power-starved. The craft’s automatic stabilization system was blocked by the failed solar panel, leaving Komarov trying to manually control the orientation of the craft. It didn’t work well.

Meanwhile, a secret second Soyuz mission was preparing to launch, carrying three cosmonauts. Mission planners wanted the two craft to meet in space and dock via an EVA. But storms at Baikonur caused mission control to call off the second flight. By Komarov’s 13th orbit, directors on the ground decided to end the Soyuz 1 mission early and bring Komarov home.

Komarov tried to descend on his 17th orbit, but the attitude control system fouled up his angle, forcing him to remain in orbit. By his 19th orbit—really his last chance, with dwindling battery power—Komarov reentered the Earth’s atmosphere, relying in large part on manual attitude control. He made it work, entering on a viable trajectory. The first (“drogue”) parachute deployed, slowing his descent a bit … but the primary parachute failed to deploy. Komarov manually activated a backup parachute, which tangled with the drogue. With nearly nothing to slow its fall, the Soyuz capsule hit the Earth, killing Komarov instantly.

Komarov’s name was included on a commemorative plaque left on the Moon during the 1971 Apollo 15 landing. The plaque honored 14 astronauts and cosmonauts (including the Apollo 1 crew) who died in the pursuit of space.

The tragedy of Soyuz 1 was a huge setback for the Soviet space program, but it wasn’t the end of the Soyuz missions. Design flaws were uncovered and fixed, and eventually the Soviet space program had a reliable launch and recovery system. We still use it today. For a look at the modern Soyuz launch system, check out this ESA video:

On April 22, 1964, New York opened its most space age World’s Fair. The centerpiece was a 120-foot diameter sculpture called The Unisphere, the largest globe-style sculpture in the world. Made from stainless steel and standing twelve stories tall, the Unisphere was meant to evoke the fair’s theme of “Peace through Understanding.” It still stands today in Queens.

The three rings surrounding the Unisphere symbolize the orbits of three great firsts in space: Yuri Gagarin, the first human in orbit; John Glenn, the first American in orbit; and Telstar, the first communications satellite.

Oddly, the Unisphere is actually the second World’s Fair-related sphere to be built in Flushing Meadows Corona Park. In 1939, the Perisphere was built in the park for that year’s World’s Fair. It was later scrapped.

To get a sense of how awesome the Unisphere was, check out this 1964 commercial advertising the New York subway:

For more on the experience of the fair, the Unisphere, and what’s left today (lots of sculptures!), check out this delightful tour by Michael D. Jackson, mixing historical and modern footage:

The Unisphere and the New York State Pavilion remained after the fair closed, but fell into disrepair. The band They Might Be Giants explored the area in their songs (they discuss the “’64 World’s Fair” in “Ana Ng” among other songs), and even shot the video for “Don’t Let’s Start” in the pavilion in 1987. The grounds were restored starting in 1989, and appeared in a variety of movies, including Men in Black, The Wiz, and Iron Man 2.

Today you can visit the Unisphere easily. Just take the #7 train to 111th Street and walk a few blocks. The fountain is only turned on in the summer, but you can visit any time. (Flushing Meadows Corona Park also contains a bunch of other stuff.)

(Header photo by Cm300883 – Own work, CC BY-SA 4.0, Link.)

On April 22, 1978, the Blues Brothers made their first performance on Saturday Night Live. Although the act can trace its earliest incarnation to a 1976 sketch where John Belushi sang “I’m a King Bee,” the full Blues Brothers concept only took shape in 1978. This was the first time we saw Jake and Elwood wearing suits, Wayfarers, and performing with their full band.

On that night, Paul Shaffer introduced the boys, claiming that they had been discovered in 1969 by the fictional “Marshall Checker.” He spun the yarn further, suggesting that the boys were washed-up hacks. He finished, “Today they are no longer an authentic blues act, but have managed to become a viable commercial product. So now, let’s join ‘Joliet’ Jake and his silent brother Elwood—the Blues Brothers.” Shaffer had helped Belushi and Dan Aykroyd recruit most of the band, and his wink-and-nod intro led into a rip-roaring performance of “Hey Bartender” and “I Don’t Know.”

Although that night’s SNL performance is something you have to pay for, there is 1978-era material online for free. The band performed extensively throughout the year, recording Briefcase Full of Blues and rounding out the year with a December 31 show closing the Winterland in San Francisco. That entire performance is online:

In this clip from a 1991 episode of Tomorrow’s World we learn about a revolution in computing: A FREAKIN’ TOUCH-SCREEN! Of course you don’t actually touch it with your fingers, you use a stylus instead. And the screen is monochrome. And it’s bulky. But still, you can kind of draw on it and that’s a big deal.

The early computers demonstrated in this clip struggle to do very basic handwriting recognition, but they do work. In a fascinating segment, they visit a Jaguar factory and note how the touchscreen is actually used in the wild, to ensure quality in paint jobs.

My favorite quote from this bit:

“It’s predicted that we will soon see an electronic checkbook which can read the amount, verify your signature, and communicate directly with the bank’s computer.”

Not a bad prediction, though of course the checkbook itself was largely made obsolete by ATM cards.

For special bonus points, after the touchscreen computer segment we learn about an exciting new technology that will allow for widescreen “high definition” TV. The future was so exciting in 1991. Enjoy:

One of the computers shown appears to be a Kyocera Refalo KX-1601, which actually ran MS-DOS!

On March 5, 1981, Sinclair Research launched the ZX81 home computer in the U.K. (It was also known as the Timex-Sinclair TS1000 in the U.S.) It came with just one kilobyte of memory, and was a self-contained unit with a rather crappy keyboard. The keyboard didn’t have moving key switches; instead it used membrane buttons similar to those often used on microwave ovens.

Despite its limitations, the ZX81 was a revolution, because it cost just £49.95 in the U.K.—massively cheaper than anything else on the market. It was also available in normal retail stores, rather than specialty computer shops.

It really was the people’s computer, and for many it was their introduction to home computing and computer programming. Incidentally, at that cheap price, it was a kit you assembled at home (a soldering iron was required). You’d have to pay an extra £20 if you wanted a pre-assembled unit. In the U.S., the fully-assembled unit cost $149.95.

The ZX81 was also expandable. You could upgrade it from its RAM using an external cartridge to bring it up to 16k—making it vastly more usable for real work. If you needed to store programs, you saved them on cassette tapes using a tape recorder. This was a finicky process, as you had to fiddle with the volume to get things just right…but for the price, it was unbeatable.

The ZX81/TS1000 sold millions, despite its limitations. Although it didn’t take over the computing world, its serious focus on retail price made it a common computer in the early home computing market. (My family had one!) It was literally a fraction of the price of competing systems. Here’s a detailed remembrance of the ZX81, showing some of what it could (and could not) do:

Here’s more detail from that interview, including a discussion of the “wobbly” RAM pack:

If you want to go deeper, read this 1982 interview with Clive Sinclair, watch this long interview with Sinclair employee Ruth Bramley. The ZX81 Wikipedia page is also quite solid.

In this riddle from TED-Ed, you’ve got a tricky math problem to solve.

In the riddle, you’re trying to infiltrate the headquarters of an enemy organization, locate a secret control panel, and shut down their death ray. There are various reasons why this isn’t easy.

First off, the enemy headquarters is a ten-story pyramid. It has a regular structure, where the top level contains one room, the floor below that has two rooms, and so on—the ground floor has 10 rooms. The control panel is hidden behind a painting, on the highest floor that satisfies the conditions listed below.

Each room has exactly three doors to three other rooms on that floor…except the control panel room, which only connects to one room. (Thus, the control panel room only has one door in it.)

There are no hallways, and you can ignore stairs while figuring the layout of the building.

You have no floor plan.

You only have enough time to search a single floor before the alarm system goes off.

Given the rules above, can you figure out which floor the control room (with its associated control panel) is on? Watch this video, and pause at the one-minute mark (when instructed), for a video view of the same problem. The solution is then presented, with a step-by-step breakdown of how to get there.

To figure out the solution, it may help to start drawing room maps, starting at the highest floor. If you’re interested in this kind of puzzle, read up on graph theory.

For more on this puzzle, check out this TED-Ed page, and be sure to visit the “Dig Deeper” section, which includes links to the puzzle author’s website, Doctor Ecco.

Why do cats have scratchy tongues? In this Deep Look video, the channel goes deep (ahem) on the functions of cat tongues. The video is presented in Ultra HD, and we get lots of ultra-closeup slow-motion cat material.

Getting back to the core question, there are lots of reasons. First, cats use their tongues to groom their coats. Their tongues have “papillae” that operate as grooming brushes, doing an effective job of removing surplus hair. Cats want to be super-clean because they are ambush predators—an errant whiff of cat scent might tip off their prey. Plus, as illustrated in the video below, the structure of a cat’s mouth and tongue make lapping up liquids a rather complex process.

Make this fullscreen and learn all about cat tongues:

If video isn’t your thing, or you’re curious about the making of this video, check out KQED’s blog post. If you just love watching animals drinking, dig this video roundup of animals drinking in slow motion.

Around the world, erosion draws sand off of beaches and into the sea. So engineers periodically dredge the sand from offshore and pump it right back onto the beaches. This has been going on for decades. (And occasionally they dredge up bombs!)

Part of our sand-loss problem is that billions of tons of sand are also used in construction (most notably in concrete), effectively locking it up so it can’t be reused on beaches. So, over the long haul, we are running out of sea sand.

Why not just use desert sand for the construction stuff? We have lots of deserts in the world, with lots of relatively bomb-free sand in them! Sadly, desert sand doesn’t work for construction because of its chemical composition. So for now we’re stuck using a resource that is only renewable on an extremely long timeline, as waves crash onto shores.

Check out this video from Tom Scott to learn more about the problem—and learn about illegal sand mining too!

Last June, a special edition of the Star Wars: The Force Awakens soundtrack was released on vinyl, with a special bonus: holograms that appear to float above, and beneath, the discs.

In the two-disc set, each has a B-side that contains music on the outer edge of the disc, and a specially etched center area. In that center area is the nifty hologram. You set the disc playing and point a directional light (like a small flashlight) at the center area. When viewed this way, two 3D holograms appear and rotate—and you’re simultaneously playing the soundtrack! The etchings were made by Tristan Duke.

The two holograms are the Millennium Falcon and a TIE Fighter. In this video, we see the holograms in action—including a test on a vertical record player, which works just as well. Enjoy: