Hear about a slingshot launching payloads into space, the impressively modern looking world’s oldest pants, and how moth wings are able to absorb sound to avoid detection from bats.
Hear about a slingshot launching payloads into space, the impressively modern looking world’s oldest pants, and how moth wings are able to absorb sound to avoid detection from bats.
A different kind of slingshot.
Very very old pants.
Moth sound absorbers.
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Find episode transcripts here: https://curiosity-daily-4e53644e.simplecast.com/episodes/space-slingshot-ancient-modern-pants-lifesaving-silence
[SFX: INTRO MUSIC/WHOOSH]
NATE: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from Discovery. Time flies when you’re learnin’ super cool stuff. I’m Nate.
CALLI: And I’m Calli. If you’re dropping in for the first time, welcome to Curiosity, where we aim to blow your mind by helping you to grow your mind. If you’re a loyal listener, welcome back!
NATE: Today, you’ll learn about a slingshot launching payloads into space, the impressively modern looking world’s oldest pants, and how moth wings are able to absorb sound to avoid detection from bats.
CALLI: Without further ado, let’s satisfy some curiosity!
[SFX: WHOOSH]
NATE: Calli, do you remember those toys in jungle gyms, some people called them merry-go-rounds or roundabouts, but it was the circular platform with handles that you could stand on and spin?
CALLI: Oh they were so fun! Though I used to spin too quickly sometimes and then you’d always get queasy.
NATE: Well, what if that's the newest step in space exploration?
CALLI: Spinning?
NATE: A new startup, SpinLaunch, has developed a system to launch payloads into low-earth orbit, the area in space that is 1,200 miles or less above the planet, where things like the International Space Station orbit. The new system uses centrifugal force from super fast rotations to launch payloads, and if it works, it could help us get into space more affordably and with less impact on the environment.
CALLI: Centrifugal force? That’s the outward force that comes when you spin something around a fixed point? Sounds like those Tilt-a-whirl carnival rides that spin and pin you to your seat. That has to be dizzying.
NATE: Fear not, we won’t be spinning astronauts. SpinLaunch has smaller, less…alive…payloads in mind. Last fall they had their first successful test and launched a 10 foot projectile thousands of feet into the air. And that was with a prototype that was just a third of the size of the launcher they want to build!
CALLI: So what does the system look like?
NATE: It starts with a circular steel vacuum chamber 300 feet across. It's like a giant bass drum with a sort of pipe or chimney coming out the top. Inside, a carbon fiber arm spins from a central point.
CALLI: Oh I am very glad they’re not putting astronauts in there.
NATE: The payload goes on the end of the arm and spins at speeds up to 5,000 mph. When it's fast enough, the payload disconnects from the arm and shoots up through the chimney. The plan is for the centrifugal forces to carry projectiles to the stratosphere… where thrusters would kick in to push it the rest of the way up to low earth orbit.
CALLI: This reminds me of that show Punkin Chunkin with those crazy catapults that launch pumpkins thousands of feet. Are those the kind of payloads we are talking about? If it's spinning at 5,000 mph, I’m not sure I’d want anything much bigger than a gourd.
NATE: The engineers expect the payloads could go up to about 440 pounds. It could be great for smaller things like satellites, orbiting experiments, or even… in a commercial setting…the ashes of loved ones who want their remains in space.
CALLI: Well that would certainly make funerals a bit more exciting.
NATE: Plus SpinLaunch says their system could reduce fuel use by 70% and reduce cost by about 90% from our current launch methods. And while those final push thrusters will likely use more traditional fuel…the launch system runs on an electric engine.
CALLI: It sounds pretty impressive, but will we need all new materials to withstand those speeds and forces?
NATE: They say it uses existing hardware and won’t require any big advancements in tech or materials. Even still, they need to do a lot more testing to ensure that payloads can withstand the impressive G’s that come with spinning at 5,000 mph.
CALLI: Well, if we don’t have to worry about rocket safety on the ground, can we do launches more quickly?
NATE: You’re right on the money. If they can perfect the system, they could likely do multiple launches a day…That could be a boon for developing systems like constellation satellites that use many small satellites working together in low earth orbit.
CALLI: That's incredible. But will the system, the company even, get off the ground?
NATE: SpinLaunch just created a partnership with NASA that requires a test later this year. They’lll need to launch and recover a payload, and show they can blow one up if it goes awry.…. They have to prove the efficacy and safety of the system and ensure it won’t harm humans.
CALLI: I didn’t know NASA was investing in this type of smaller project. I’ve got some good ideas that sound less crazy than this!
NATE: I’m sure someone has already tackled your “space bacon” idea Calli, as much as our astronauts do deserve a new and exciting breakfast food. The partnership comes from the Flight Opportunities Program that allows researchers to demonstrate new and promising tech for space exploration, discovery, and commerce.
CALLI: So if everything goes well, when might we actually see it in use?
NATE: SpinLaunch hopes to deliver the first payloads to low Earth orbit by 2025, and they have a lot of partners like Airbus and Google that are interested in seeing that happen.
CALLI: From gym class to the atmosphere, that’s a big step for centrifugal force.
NATE: Well I’m glad your friends never spun you into orbit.
CALLI: You and me both!
[SFX: WHOOSH]
CALLI: Nate, you might think archeologists only deal with bones, but I’ve got a story today about something far softer, and impressively modern.
NATE: Soft and modern? Is it an ancient bed or something?
CALLI: Even better! Archeologists have found the world’s oldest pair of pants and they look shockingly modern. Their complex weaves and mixed patterns show how specialized, and wide ranging, clothing production was even 3000 years ago.
NATE: Where’d they find them? That’d be quite the thrift shop find.
CALLI: Chinese archeologists found them in a cemetery in northwestern China, and the things they found with the pants suggests they belonged to a horse riding warrior.
NATE: What kind of rad things do you need to stand out as a horseback warrior?
CALLI: The pants were part of a burial outfit that included a poncho, ankle boots, a headband with seashells and bronze disks, and the warrior was surrounded with a bridle, battle ax, and horse bit. Presumably things he loved in life.
NATE: People still do that today, I know folks buried with pictures of their loved ones.
CALLI: Sure, but even with all this neat equipment, his pants were the most interesting. Using carbon dating on the wool fabric, researchers think he was buried in them between 1000 and 1200 BCE. Impressively, they had three distinct woven patterns that made them purpose built for riding.
NATE: Were they zip-offs for when it got hot?
CALLI: Most of the pants were made from woven twill, a diagonal ribbed weave like we use in jeans. This helped make the hearty and stiff wool fabric flexible, great for getting on and off your horse without being restricted or tearing the back.
NATE: There is nothing worse than tearing the rear seam on a pair of pants.
CALLI: Has that…happened to you?
NATE: No comment.
CALLI: Well thankfully these pants actually did not have any seams or cuts in the fabric. It means the fabric was likely woven specifically to fit this warrior, the Turfan Man as archeologists call him. And they were made to move! The crotch was wider in the center to allow the pants to move and bunch during the extreme movements of riding.
NATE: Kind of like work pants built for specific motions?
CALLI: Exactly. But that's not the only special feature. The knees also had a different weave, called a tapestry weave, that was less flexible, but made the fabric more durable. The waist had a third weaving technique that created a thick waistband to keep the pants in place and comfortable.
NATE: I suppose you don’t want to be pulling your pants up as you fight from horseback.
CALLI: Can’t have that. The variety of weaving techniques, in the same pair of pants, blew the minds of the archaeologists. They worked with modern weaving experts to recreate the pants and they ended up looking so modern!
NATE: It's pretty impressive that a single weaver could be an expert in all of these techniques. Did this culture just excel at making textiles?
CALLI: Well fabric is interesting. The oldest piece of twill weave we’ve found is from Austria and about 200-500 years older than these pants. While there is a chance both cultures developed the weave independently, the styling of the pants suggests that there was likely a lot of contact between the warrior’s culture and other groups.
NATE: Styling? They’re patterned pants?
CALLI: Well different kinds of decorative weaves. There is a weave that looks like a pyramid suggesting the weavers may have had contact with Mesopotamians. And there is an interlocking design of T’s that’s also been found on bronze containers in China and western Siberia, places more than 1800 miles away. And that tapestry weaving on the knees? It is believed to have originated in southwestern Asia.
NATE: That’s an unbelievable distance. I guess you’d need some tough trousers for all that.
CALLI: Seriously, all these cultural signifiers have archeologists thinking that these migrating herders and warriors picked up ideas and techniques from different cultures in the very earliest days of the trading route, the Silk Road.
NATE: Who knows how many stories our pants could tell!
CALLI: Well I think it shows that we really haven’t changed much. There is nothing like a favorite pair of pants.
[SFX: WHOOSH]
NATE: Calli do you remember that movie, A Quiet Place, where the characters had to avoid making noise or else a monster with super hearing would catch them?
CALLI: Oh I loved that one. Wait, are you about to tell me about real monsters listening to us?
NATE: Sort of, but they’re not hunting humans, they’re hunting…moths!
CALLI: You’re telling me moths are actually LIVING the plot of the movie? What is hunting them down?
NATE: Bats! Bats are natural predators of moths. When bats hunt, they use echolocation to send out a sound and listen as the sound waves bounce off of things and back to them. By doing this, they can sort of “see” what’s around them, including moths, even in the dark. But a new study found that moths are fighting back. To avoid being eaten, they’ve developed wings that can absorb much of those echolocation sounds to keep them from bouncing back to the bat. Learning from these flying creatures could be a huge help for our efforts to sound-proof areas like recording studios, our homes, and the inside of commercial airplanes!
CALLI: So John Krasinski might have been able to avoid detection by surrounding himself with a cloak of moths?
NATE: That might have actually worked! That’s because the moths’ wings are covered in tiny scales of various sizes. Each of these has its own resonant frequency, which means each scale is good at absorbing a certain pitch of sound. With the variety of scale sizes, the moth can absorb a broad range of sounds and make it harder for the bat to find them!
CALLI: How much of the sound do they absorb?
NATE: A research team wanted to see just that, so they placed small parts of moth wings on aluminum discs, and then sent soundwaves at them. They regularly repositioned the discs so the sound waves would hit at different angles.
CALLI: What did they find?
NATE: They were GREAT sound absorbers. 87% of the sound that was sent to the wing was absorbed!
CALLI: That doesn’t even sound possible! Moth wings are so small!
NATE: This blew researchers away, not in small part because we don’t have the technology to make such ulra-thin sound absorption with conventional materials. Sounds have a wavelength, and the scales were only 1/50th the thickness of the specific wavelength they were built to absorb.
CALLI: So what does this mean for the future? Are we going to try to make something similar with conventional materials?
NATE: The researchers believe technology like this is going to be necessary for the future of humanity. Cities get louder and louder every day with the increase of cars and population, and noise pollution is at an all time high. In the future, we might be able to borrow what we learn from moths and create soundproofing so thin you could put it on your walls like wallpaper and create a peaceful sanctuary in a loud world!
CALLI: Oh that sounds so nice! When can I plaster up some sound absorbing to keep from hearing my neighbor’s late night movies?
NATE: Well there is still a lot of work to be done. One of the biggest challenges is that moths use their wings to absorb sounds in ranges that we can’t hear, they’re too high. If researchers can adapt what they learn, though, and make something similar to absorb sounds in our audible range, it’ll give us far thinner, and lighter options than the foams and such that you see in places like recording studios today.
CALLI: I get why being thinner would be such an advantage, but why does being lighter matter?
NATE: Lighter materials could make a huge difference for things like travel! Right now it’s hard to make the inside of cars and planes quieter, because our current soundproofing materials are so heavy they actually have a negative effect on fuel efficiency. But if we could use much lighter materials, we could maintain that efficiency while making the inside of planes and cars way more quiet. Think of it, no more need for those noise-canceling headphones in coach!
CALLI: Well I hope their prototypes go well, we could all use a little quiet.
NATE: Whether there are monsters hunting us or not!
[SFX: WHOOSH]
NATE: Let’s recap what we learned today to wrap up.
CALLI: A new startup has created a promising new way to launch payloads to space, and it has caught NASA’s eye. The cheaper and more environmentally friendly system uses centrifugal force to spin small payloads at incredible speeds and launch them into low earth orbit.
NATE: Archeologists in China have uncovered the world’s oldest pants, and even though they are about 3000 years old, they look shockingly modern. The purpose-built trousers use a variety of weaves that impressed archeologists and suggest that even thousands of years ago trading between cultures was an essential part of life.
CALLI: New research has illuminated the surprising system moths use to avoid detection by their bat predators. A series of various sized, ultra-thin scales absorb up to 87% of sound to help the moths from being detected by the bat’s echolocation. Learning how the scales work could greatly improve, and lighten, our manufactured soundproofing materials.