We've spent more than 100 years illuminating the darkness with electricity. Over time, those electrical systems got bigger and more automatic. Randall Munroe's What If series (previously at Neatorama) received the question, "If all humans died, when would the last light go out?" To answer the question, Munroe completely ignored the theoretical scenario of our demise and got straight to the lights. It comes down to the power source, since some are more automatic than others. Those relying on fuel delivery will go out first, but some kind of artificial lights will last for way longer than you might think. And then we must consider what we mean by "artificial lights." Enriched nuclear fuel gives off a light even though we don't use that light for everyday (or every night) activities. Commenters brought up even more lights, like the Voyager space probes, which have manmade lights, although they are not on earth. There's also the burning coal seams like in Centralia, Pennsylvania, which are natural, but were ignited by human activity. They can burn for thousands of years, but whether you term them as manmade or artificial lights is a matter of semantics.

There are some references in this video you might want to look up, like the Radium Girls, the future of nuclear danger, and Tom Scott. The Rhode Island sign is reference a previous What If video.

Submarine technology is older than you probably think. Cornelius Drebbel built one for the King of England in 1620! Early submarines were successful until they weren't, and the bottom of the ocean is not a good place for the preservation of a wooden submarine. American school children learn about the H. L. Hunley, an ironclad Confederate submarine that sank a Union ship, but was ultimately a failure because all the crew members on each of its three missions died. The sunken Hunley was found in 1970 and raised in 2000. But it is still not the oldest existing submarine.

That would be the Brandtaucher, shown above. This iron submarine was Germany's first, built by Wilhelm Bauer in 1850. It was 28 feet long and weighed 70,000 pounds. Believe it or not, it was powered by two men on a tread wheel! The Brandtaucher wasn't any more successful than earlier submarines, and sank during its first demonstration. However, Bauer learned from his mistakes and went on to design better submarines for the German military. Read about the Brandtaucher, the oldest existing submarine, at Amusing Planet.

(Image credit: Jan Rehschuh)

Leonard Solomon has made a career out of building and performing on his own musical instruments. We've featured videos of his bottle organ and his oomphalapompatronium in previous video. In this video, he demonstrates that 21st century music, too, can easily be played on his weird instruments. Listen as he recreates Skrillex's 2010 song "Scary Monsters and Nice Sprites" on his instrument called a squijeeblion. It produces sounds that range from a nice melody to a foghorn fart to a crying beagle, and you better believe the bass drop is there, too. EDM will never be the same, although you can't really call it that, since this song was played with no MIDI involved. Also, the squijeeblion is powered by air, with both breath and bellows. Too bad you can't go down to the music shop and pick up your own squijeeblion. -via Metafilter, you'll find lots more of Solomon's music linked.  

The Knights Templar was an order of wealthy and pious warriors who fought in the crusades. The order existed for 200 years, and their legend lives on in documentation and in imagery. One of the most mysterious examples of that imagery is the Templar seal, used to stamp and identify correspondence sealed with wax. The stamp, pictured above, shows two knights sharing one horse. What is the significance of this symbol?

The symbol has been interpreted in many ways. It could signify the Templar's vow of poverty, portraying knights having to share a steed. Or it could mean brotherhood, as in carrying each other. Or it could be a symbolic representation Christ being with them. Or it could be a subtle indication of homosexuality. Or possibly a combination of any of these, or something that no one has considered before. To really know, you'd have to ask a Knight of the Templar order, and they've been gone for more than 800 years. Read about the seal of the Knights Templar and how it has been interpreted at the Conversation.

(Image credit: Hinterkappelen)

One of the funnier lines in the 1974 movie Young Frankenstein was when Igor (Marty Feldman) told Dr. Frankenstein (Gene Wilder) to "Walk this way." He didn't mean the direction, he meant the style. "No, walk THIS way!" A few months later, the song "Walk This Way" by Aerosmith was a hit. My friends and I would dance to it, and walk like Igor during the chorus. Yeah, it was funny. It turns out the song was actually named after that line in that movie! The music came first, then guitarist Brad Whitford saw Young Frankenstein and found the line so funny he insisted on using it for the song. Steven Tyler wrote the rest of the lyrics around the phrase. If that's not wild enough, wait until you find out exactly who inspired the song "Dude Looks Like a Lady."

Mental Floss takes a deep dive into the origins and meanings of 25 hit songs that you never really thought about, many of which changed considerably between the inspiration and the finished product. You can also listen to the list in the form of a video at the same link.  

Theodore Roosevelt was America's 26th president, after raising cattle in North Dakota, fighting in the Spanish-American War, and serving as governor of New York, among other adventures. Many legendary but true tales are told about Teddy, including the one in which the Teddy bear was named for him. But there are always more. I have written about Roosevelt several times, and one even I hadn't heard of happened sometime around 1884.

Roosevelt entered a bar in Montana and saw that one guy was so drunk he had already shot the clock on the wall three times. Holding two guns, he mocked Roosevelt for wearing glasses and ordered him to fix drinks. Roosevelt managed to convince the drunk fellow that he was no danger, then punched him good, knocking the guy unconscious to the cheers of everyone in the saloon. The drunk left town and never came back. When Roosevelt told the story in his autobiography, he included a lot more details. You can read that one and five other true stories that show just how fearless Roosevelt was, at Cracked.

Drug lord Gustavo Fring (played by Giancarlo Esposito) made quite an impression as the toughest of tough guys on Breaking Bad. He managed to bluff his way through and survive many attempts on his life during the series with style and menace, so (spoiler coming) when he was eventually assassinated by a nonverbal colleague in a wheelchair, we were doubly shocked. What kept him alive through so much mayhem? Plot armor, produced by the character's popularity. By the time Fring actually died, we were all convinced he would be around forever. YouTuber Alternative Cuts (previously at Neatorama) spent two months editing together a video illustration of how bulletproof Fring really was. He confidently steps into danger, brought by all the badasses from Breaking Bad, then by other movie characters who shoot to kill. The walk gets longer and longer as every cinematic killer, no matter how ridiculous, is thrown at him. That's one tough character. -via Geeks Are Sexy

We all know about the ridiculous varying pronunciations of cough, tough, bough, through, and though, which are all spelled alike but cannot be made to rhyme successfully. It's just one of the many ways that English is thoroughly weird, and very hard to master if it's not a language you learned in early childhood. How did English spelling get this way? To begin with, English is a mishmash of other languages, constantly changing over the centuries. Ever tried to read something in Old English? When the spoken language began to be a printed language, there was no authority over spelling, like a bureau of language standards. Words were spelled whatever way the printer wanted, usually to give some idea of how they were pronounced. But pronunciation changes over time and place, and the printed word, for the most part, stays the same. That's why we can still read Shakespeare, but we are probably not using the same word pronunciation. -via Laughing Squid

What period of history is most like the early internet? It had to be the medieval era, when the only books were hand-copied by bored monks and no one knew how to read anyway. No one knew what an elephant looked like, either, but you only needed paint to give it a try. There were so many jokes illustrated in pictures that you have to wonder about the ones they told.

No one appreciates those things more than Matt Ponesse, history professor at Ohio Dominican University. At Instagram, he's medievalistmatt, who gives us a glimpse into the way things were back then with a dose of laughs.

Looking through his gallery of memes can suck up the rest of your day. And always check the captions for more pithy remarks and the source of each image, which sometimes even includes the year. I may have learned a little about medieval history along the way. I bet Ponesse's classes are a blast. -via Boing Boing

The Great Lakes of the US and Canada are the world's largest freshwater ecosystem in the world, and those who manage it have been battling invasive Asian carp for 50 years, to the point that migrating fish must go through gates and be sorted or rejected by species. But as conservationists are starting to win the battle against carp, they are confronted with a growing number of goldfish in the lakes. They started out as discarded pets, but in the wild, they grow to enormous size and reproduce like no one's business. They displace native species and wreck the ecosystem.  

Goldfish are commonly a beloved family pet, but when they outgrow their tank or otherwise must be discarded, people understandably don't want to take the easy way out, like, say, feeding it to the cat. Flushing a goldfish seems cruel, and does not guarantee their death. To solve this dilemma, the Erie Zoo launched the Last Chance Lagoon, a place to "retire" pet goldfish without releasing them into the wild. The zoo has taken in 52 pet goldfish. That doesn't seem like much, but it may inspire other communities to launch similar programs to keep goldfish out of public waterways.   

People have always gambled because the rush of winning is perceived to be worth the risk of losing. In the 1600s, enterprising folks figured out that the real money is in hosting other people's gambling addictions, and they were right, but they didn't understand the odds even then. Meanwhile, mathematicians began studying the science of probability.

The owners of gambling houses sought to increase their profits by guiding patrons to games with long odds, which works because those patrons didn't understand probability, either. But the brothers Johann and Jacob Bernoulli came up with the law of large number or long averages in 1713 (the Golden Theorem), which proved that even with only a very small advantage, the house will always win if people play the games long enough. Abraham De Moivre tried to explain the concept to gambling parlor owners, but they and the gambling public were mostly illiterate and understood numbers in only the simplest terms. It took a long time for operators to realize that they could make plenty of dough even without cheating, and fair games would draw more participants.

History professor John Eglin explains this small advantage using roulette, in which the house has a small chance of winning without risking any money. That small chance will eventually make a casino tons of money, but it took hundreds of years for people to understand that. Read how mathematical laws make money for casinos at The Conversation.  -via Damn Interesting
 
(Image credit: Thomas Rowlandson)

In 1960, an ancient suit of armor was discovered in the Greek village of Dendra. It has been dated to around 1,500 BC, making it a part of the Mycenaean civilization, which ruled Greece at the time. The armor is made of plates of copper alloy, held together by leather strips, and would cover a soldier from face to knees, supplemented with arm and leg pieces and a helmet decorated with pieces of boar tusks. The Dendra specimen was in strangely good shape, and might never have been used in battle. That brought up a question- was this armor designed to be used during warfare, or was it ceremonial? It seemed to be too hot and heavy to be worn by actual warriors.  

To see if this armor could be used in battle, 13 exact replicas were made of the armor, and actual Greek soldiers from the 32nd Marines Brigade of the Hellenic Army were recruited to fight while wearing those replicas. To recreate battle conditions from 3,500 years ago, the soldiers ate a meal typical for the military of that time and were put in a temperature-controlled environment. Fight choreography was taken from Homer's Iliad. They fought for 11 hours with replicas of Mycenaean weaponry. You can see a video from the experiment here. Read about this re-enactment, er, experiment, and what we've learned about the Dendra armor at Smithsonian.

(Image credit: Zde)

When you're playing Super Mario Bros. 2, or any other adventure game, you keep your eye out for new challenges. When you see something new or different, you go for it. What's the worst that could happen? You might waste time not getting points. Of course you go for it, and you never stop to think about the implications for anyone else, because you're just thinking about yourself, aren't you? Yeah, I thought so. Maybe before you pull someone's turnips out of the ground, you could stop just a minute and look up what those turnips really mean. Sure, it cost you a few seconds for nothing, but the folks who planted those turnips were counting on them for survival. It's easy to point out Mario as the bad guy, but who's playing this game, anyway? This pixilated cartoon from Dorkly is only two minutes long, the rest is credits and promotional.  

Science fiction and fantasy author Ellen Klages was once asked to fill time during the Nebula Awards ceremony while technical difficulties were worked out. She told a personal story about her father's Smithfield ham. He received it as a gift some time in the 1990s, and knew that Smithfield hams were supposed to improve with age. They have already been aged in a smokehouse before purchase, but he wanted to age it more, so he hung it in their damp basement. For years. When asked, he always had plans for the ham, but never got around to them. Klages' father died in 2008, with the ham still in the basement, permanently covered with a thick layer of mold. Klages and her sister, who had avoided the scary ham as best as they could, had to dispose of it some way. Her sister wanted a Viking funeral, or maybe they could just leave it somewhere, but they were afraid that would get them in trouble.

They put off disposing of the ham until all the other details of her father's estate were taken care of. By then they had arranged an elaborate funeral that you have to read about, accompanied by pictures of the event. Some people just know how to tell a story. -via Metafilter

(Unrelated image credit: Isle of Wight County Museum)

Yes, we manage to blow things up real good. MetaBallStudios (previously at Neatorama) takes us through the power of various explosives starting with a firecracker, which is not supposed to kill anyone but could under the right circumstances. Most of the other devices here were intentionally designed to kill. The comparison moves up through ever-more destructive explosions. Not all bombs are included; the ones they selected have quite enough power, thank you very much.

Some of the real historical explosions are shown happening in fictional scenarios so that we can picture in our minds and understand the effects better. For example, the atomic bomb detonated over the city of Nagasaki in 1945 is shown as if it were deployed over modern-day Tokyo, and the 2020 Beirut explosion (which was an industrial accident and not a bomb) is shown happening in New York City. That can be pretty unnerving. -via Geeks Are Sexy