Have you ever looked at something through a magnifying glass? Have you ever wondered what a butterfly’s wing, an ant’s jaws, or a blade of grass would look like if you were the size of a bug and could see it really close up? Even though most magnifying glasses don’t make things look that much bigger, you can see a lot more detail. You can see the tiny veins on a maple leaf, or maybe the little feathery bits of a moth’s antennae. But if you could magnify things by 50 or 100, or 200 times–far more than a magnifying glass can–you’d see even more detail. You might even see individual cells, the smallest parts of living things.

In the 17th century, people were just starting to make tools that could magnify things more than typical magnifying glasses. Galileo made telescopes to peer out at the stars and planets, magnifying far-off things to make them look a little closer. Other scientists began making microscopes, which looked a lot like miniature telescopes and made tiny things look bigger. But these early microscopes weren’t very strong. They only made objects look about 20 or 30 times bigger. But Antony van Leeuwenhoek, a cloth merchant from Holland with little formal education, would change all of that. 

Antony was born in Delft in 1632, to an ordinary, middle-class family. His father was probably a basketmaker. Delft itself would have been an exciting place to grow up though: It was a flourishing market town. It produced a famous style of blue-glazed pottery and was a stop for trading ships due to its canals. 

Antony got involved in commerce early. He raised silkworms and sold them to silk merchants who would transform their cocoons into delicate, luxurious cloth. Antony’s family was comfortable, but not enough to give him the education it would take to become a scientist. Being from a family of tradespeople, he was sent to Amsterdam at 16 to learn his own trade or a job that he would spend his life working at. He became an apprentice, or trainee, to a draper, and learned about the business of making and selling cloth. He became a master of this trade, then moved back to Delft to open his own shop. 

Being a draper, Antony had to use magnifying glasses as part of his job. He used them to examine cloth samples before he bought them. He would peer through one to carefully count the threads in a section of cloth, noting whether they were straight and smooth, before deciding what he would pay a trader, and how much he could charge customers for it in his shop. Maybe as he was hunched over scrutinizing cloth, he sometimes thought back to his silkworms and wondered what their tiny jaws or feet would look like under that same magnifying glass. 

But as a young man with a business and growing family, Antony probably didn’t have much time to look at bugs under his magnifying glass. He worked hard at his shop, and became involved in his community, serving in several jobs in the city government. But, he did start to experiment with making better lenses to help him see the cloth, and as time went on, his curiosity about the world he could see under those magnifying glasses only grew. 

Around 1668, Antony had the chance to visit London, England. It was probably while there, that he first saw a book by an English scientist, Robert Hooke called Micrographia. Hooke worked with microscopes. Even though they weren’t very powerful and could be blurry, Hooke had managed to observe and sketch hundreds of fascinating objects– molds; moth wings; plant roots; and the sharp, stinging points of nettles.

Antony was captivated. He wondered what else he might see if he looked. He also wondered whether he could make his own microscope that would work even better. After all, he had experience making lenses, the most important part of a microscope, for his cloth trading business. But what Antony would create turned out to be capable of much more powerful magnification than anything else ever built.

After many years, Antony earned enough money from his cloth trade, inheritance, and city jobs to close his shop. He used his new free time to practice his new hobbies: creating lenses and building microscopes. He ground some of his lenses down from pieces of glass using sand. Others he made by melting glass and using a tiny, red-hot droplet which he worked into a nearly-round shape as it cooled. The lenses made from blown, melted glass were especially clear and probably allowed Antony to make some of his most amazing discoveries about the microscopic world. Some were almost just tiny beads, and others were shaped like discs that curved outward on both sides, like a lentil. If you have a magnifying glass at home, the glass in it will also have this lentil shape if you run your fingers over it.  

Not only were Antony’s lenses different from previous microscope lenses, but his microscope’s designs were also completely different too. Instead of making a microscope that looked like a smaller telescope, with a lens at each end, Antony would sandwich one lens between two metal plates, each with a small hole, just a bit smaller than the lens itself, to hold it in place. A screw was mounted onto plates to adjust how far the sample (the thing being observed) was from the lens. Antony’s microscopes were small all over: most measured one inch by two inches! Instead of sitting on a table, like other microscopes of the time, you would hold one right up to your eye to see the sample. 

But even if they were small, Antony’s microscopes were revolutionary. The lenses were very clear and high quality. And where older microscopes magnified things about 20 to 30 times, Antony’s made objects appear about 200 times larger! Antony became obsessed with looking at things under his microscopes. He measured everything and drew detailed pictures. He looked at the jaws of bumblebees, wood, blood cells, lice eggs from his socks, and much more. He was constantly looking for specimens to study. 

One day, Antony collected some water from a pond. It looked completely clear and fresh. But, even though nothing was visible when he looked at the water with his eyes, under the microscope he saw a world crowded with life, a multitude of tiny organisms swimming around. This was a stunning discovery. No one even suspected that living things might be swimming around in clean water! But because his microscopes were so powerful, Antony was able to make the invisible visible. He called these life forms “animalcules”, or “tiny animals” in Latin. 

He also scraped the gunk off his own and his neighbors’ teeth, smearing it onto his microscopes. Antony took time each day to scrape his teeth clean, which was unusual for the time. He compared his tooth gunk to that of his neighbor, who rarely cleaned their teeth. He noticed far fewer animalcules hanging out in his own tooth goo than that of his less-hygienic neighbor.

Antony sent his drawings, measurements, and detailed descriptions to the Royal Society of London. The Society was a group of the most prominent scientists of the time. Robert Hooke, the author of Micrographia, was a member. Many in the Society doubted that Antony was telling the truth about his discoveries. They had never seen the kinds of things Antony described under their microscopes.  Hooke was skeptical too, but he decided to try to observe similar samples for himself. After months of trying, Hooke was finally able to see some of the tiny beings that Antony had described. He presented the findings to the Royal Society, and they finally invited Antony to join the group. He never attended any meetings in person but did keep writing letters to the Society until his death fifty years later, detailing discovery after discovery. 

As his reputation spread, many people visited Antony’s workshop to look through his microscopes. The Czar of Russia spent two hours observing his specimens! But Antony was secretive about how he made his microscopes and kept the best ones hidden away from visitors. He never wanted to teach others just how he made his high-quality lenses either because he felt it would take too much time away from his own observations. Unfortunately, only a few of his microscopes survived, and others would take years to reconstruct the knowledge of how he built them

Even so, Antony’s observations revealed a whole new world of life that had been invisible up till then. Eventually, others would discover that some of the denizens of this invisible world caused diseases. Nineteenth-century scientists like Louis Pasteur and Alfred Koch would make these connections over 200 years later. In the 20th century, scientists would delve even further into the invisible, studying the internal machinery inside animal and plant cells and bacteria, using microscopes even more powerful than Antony could have imagined or devised. We also came to understand that not all members of this invisible world are responsible for diseases–many don’t bother us at all, and some even help us. 

Antony van Leeuwenhoek made his microscopes and observations with very little formal education or support. He didn’t speak the languages used by scholars of the day–English, Latin, and Greek. He only spoke Dutch. But he made over 500 of his tiny microscopes and spent nearly every day for fifty years observing. He looked at anything and everything under his microscope. He didn’t need a reason, his curiosity just drove him to look. 

What are you curious about? How can you learn more about it? Whether you read about it in books, observe it under a microscope, or set up an experiment, follow that curiosity! You never know what you’ll find.

Sources

https://www.bbc.co.uk/history/historic_figures/van_leeuwenhoek_antonie.shtml

https://micro.magnet.fsu.edu/primer/museum/hooke.html

https://ucmp.berkeley.edu/history/leeuwenhoek.html

Curtis, Robert H. (1993) Great Lives: Medicine. Macmillan, New York.

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Tesla Car Company

Have you ever heard of a Tesla car? Teslas are very fast cars, but unlike most sports cars, Teslas are electric-powered not gas-powered. Teslas are becoming very popular because they are one way to prevent carbon emissions and help the environment. Although you may be familiar with the name Tesla because of the famous car, you may not be aware of where the name came from. Tesla cars are named after an inventor named Nikola Tesla. Tonight we’re going to learn more about Telsa and why he became so well known.

Nikola Tesla’s Birth and Early Life

In 1865, Nikola Tesla was born to Serbian parents in what is now known as Croatia. His father was an Orthodox Priest and his mother never went to school but was a very intelligent woman. She was known for inventing her own electrical gadgets to be used around the house. Nikola later said his great intelligence came from his gifted mother.

Growing up Nikola went to school like most kids and studied German, math, and religion. They moved to a new town where his father was a priest and there he attended elementary and middle school. During high school, Nikola had a physics teacher who showed his class the power of electricity. When Nikola saw it he was amazed and wanted to learn more about this wonderful force. It was here that Nikola did so well in his math classes that the teachers thought he was cheating because he could do difficult math in his head, without using paper.

Nikola Tesla’s Education

Not long after graduating from high school, Nikola became very sick and spent nine months in bed, but finally, he got better. His father wanted him to become a priest like he was, but Nikola was more interested in engineering. Engineering is the science of designing and building things. 

Nikola went to the university in Graz, Austria for a time and did very well there. It was there that he first learned about a dynamo, which is used to generate electricity. He started to have ideas about how he could make it work better. Nikola worked very hard while in school. It was said he worked from 3 am to 11 pm and didn’t take breaks on the weekend. His friends and family worried if he didn’t slow down he would become sick from over-working himself.

After university Nikola moved to the country of Hungary and started working for a telegraph company. The telegraph was used to communicate by sending signals along a wire before the telephone was invented. While there, Nikola helped them improve the telegraph equipment! 

Thomas Edison

Nikola Tesla’s next job was in Paris working for one of Thomas Edison’s power companies. Thomas Edison was a famous American inventor known for designing the lightbulb among other inventions. From there Tesla moved first moved to America and got a job working directly with Thomas Edison. He was very poor at the time and arrived in America with only a few cents in his pockets and a few poems he had written. 

Alternating Current

Unfortunately, his work with Thomas Edison didn’t last long. Instead, Tesla took his ideas to Edison’s competitor, George Westinghouse, who bought his idea for the alternating current dynamo. Direct current is what Thomas Edison used and worked by sending an electrical current one way, but Tesla’s idea was to switch the directions in the current was sent. To this day Tesla’s alternating current is used more than direct current. 

Tesla’s Other Inventions

Next, Tesla started his own lab and experimented with ideas that helped pave the way for the x-ray. He also created the Tesla coil, which was later used for sending radio waves through the air or radios and televisions. It was around this time that the World’s Columbian Exposition was to be held in Chicago in 1893. This was an enormous world fair where people from all over the world would visit Chicago to see exciting new inventions and experience new things. This also started a competition between Thomas Edison and Nikola Tesla over whether AC (alternating current) or DC (direct current) would be used to power the huge world’s fair. In the end, Telsa’s alternating current won the match and it was used to power the World’s Columbian Exposition. 

Telsa went on to create the first hydroelectric power generator at Niagara Falls, New York. Hydroelectric means water power is used to create electricity. 

Telsa’s next big project was a huge electrical tower in Long Island, New York, which he planned to use to send radio waves all around the world. It was called the Wardenclyffe Tower. At this time a different tower was being built by Guglielmo Marconi to do a similar thing. Tesla got started on his tower, but Marconi beat him by sending a signal across the Atlantic Ocean first. This caused the people paying for Tesla’s tower to change their minds causing the project to fail.

Nikola continued to come up with new ideas, but most of his designs stayed in his notebooks and he didn’t get a chance to actually build them. 

For anyone who listened to the last Bedtime History episode about Mark Twain, you’ll be interested to know that Mark Twain and Tesla were friends. While growing up, Tesla read many of Mark Twain’s novels and so he was excited to finally meet him after moving to America. Twain was interested in Tesla’s inventions and often visited his lab and participated in experiments. He also gave him money to help with his new inventions.

Later in Nikola Tesla’s life, he won awards for his past inventions, and in 1937 when he passed away many around the world mourned his death. Someone was quoted as saying that he was “one of the outstanding intellects of the world who paved the way for many of the technological developments of modern times.”

Conclusion

Nikola faced many difficulties in his life, but he continued to learn and apply his mind to designing new things and improving the things around him. Like Tesla, you can be curious about the world around you. In school, he saw the power of electricity and wanted to learn how it worked. He found new ways to use it to improve the lives of people all over the world. Learning how to invent and improve things is a combination of learning how the forces in the world work, like physics, and what things are made up of, called chemistry — and then using creativity to apply that knowledge about the world. This is why it’s a good idea to pay attention in school and take the time outside of school to dig deeper and really understand how the world works.

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Imagine you are floating in a spacecraft…

You are weightless! It feels so strange, yet amazing at the same time. You push off the wall and float down a long room. You feel like Superman flying across empty space. You duck your head and do a quick flip before landing against the other wall, then push off it to soar in the opposite direction. At the end of the next room, you grab a handle and stop to look out the round bubble window. Far below you see a glittering blue ocean, clouds, and brown land. You are 200 miles above earth on board the International Space Station.

Speed and Orbit

Have you ever heard of the International Space Station? Right now it’s circling the earth above you at 17,000 miles per hour (28,000 kilometers per hour). It is going so fast that it orbits the earth every 90 minutes — that means 15 ½ times a day! That’s incredibly fast! Some people think the Space Station is floating in space, but it’s actually falling around the earth in what is known as an orbit. 

The International Space Station, also known as the ISS, is special because it’s not owned by a single country, but by many countries who worked together to build it. It started off as a single module and has grown piece-by-piece into the larger station it is now. In 1998 Russia launched the module Zarya into low earth orbit as the first piece. Low-earth orbit means it is still within the earth’s orbit, not far off in space beyond the earth’s strong gravitational pull. 

Construction

Two weeks after Zarya was launched, the United States launched its own space shuttle with the Unity module and its astronauts onboard. The next step was connecting the first two modules. The astronauts did this by floating out into space and attaching them. And that is how the International Space Station began!  After that other pieces were slowly added to the ISS until it grew and grew. In 2000 came the Russian module Zvezda, then NASA’s Destiny module. Canada’s space program contributed a robotic arm for spacewalks and to make remote controller repairs. The Harmony module came in 2007, then the European Space Agency sent up the Columbus module. Japan sent up its own module in 2008. Next came NASA’s Tranquility module, then Europe’s Leonardo module and finally the Bigelow module sent up by a private company. One reason ISS is amazing is that it is a team effort!

Space Station Activities

Usually, around 3 to 6 astronauts live and work on the ISS at a time. It was made for many reasons, but one of them was to do research. Since humans plan to go to Mars someday, they are using the ISS to see how space will affect the astronauts during their journey to Mars. For example, what will space flight do to their bodies? What kind of foods will they need to eat? What kind of exercise will they need? Will they be able to grow plants? They’ve also tried out the different devices they’ll need in space such as 3D printers and coffee makers.

On the ISS the crew’s days are very busy and besides doing experiments, they spend a lot of time doing maintenance — which means keeping the station running smoothly. Each astronaut has different responsibilities, sort of like you might have doing chores at home. Only by working together will the ISS continue to work properly. Often the astronauts climb into their space suits and space walk — which means going outside of the ISS and floating around to make repairs. This can be dangerous work, so they always attach themselves to the ISS for safety. The astronauts have also been testing a robot that they can use to fly around the ISS and make repairs for them.

The other important part of an astronaut’s day is taking care of themselves, making sure they eat the right foods, showering, brushing their teeth, and getting exercise. They also do things like video chat with schoolchildren and talk about what they’re doing with people around the world. They do this to get others excited about the space station and space research. 

Eating in zero gravity can be very tricky! Their food has to be strapped down to a table and utensils and water bottles have magnets on them to keep them from floating away. If you look on the internet you can find some funny videos of the crew doing flips, floating around and dancing, and playing with water. In zero gravity water floats around in blobs!

Space Station Crew

People from 19 different countries have visited the ISS. These include the United States, Russia, Japan, Canada, Italy, France, Germany, Belgium, Brazil, Denmark, Kazakhstan, Malaysia, the Netherlands, South Africa, South Korea, Spain, Sweden, the United Arab Emirates, and the United Kingdom. Now you see why they call it the International Space Station. International means “many countries.” At the ISS it’s exciting to see people from many different countries working together. It’s a perfect example of how working together with people across the world can accomplish amazing things! 

Space Tourism

Many people dream of visiting space someday and some companies promise that someday anyone who can pay for it will be able to do it. Right now it can be very expensive (and at times not even possible) to visit places like the ISS, but someday space vacations may be available to everyone. Can you imagine visiting a place like the ISS or a far-off hotel on the moon? This is called space tourism and a few very wealthy people have been able to visit the ISS by paying for it. It costs them many millions of dollars! 

Anousheh Ansari

One of these people was Anousheh Ansari. Anousheh was born in Iran and moved to the United States when she was little. She was interested in engineering and graduated from college to become an engineer. She and her husband later started a company that grew and grew until they were very wealthy. She’d always dreamed of going to space and became interested in visiting the space station. When she found out they were allowing some to visit the ISS if they paid, she jumped on the chance. First Anousheh trained for the journey, then took a Russian rocket up to the ISS and lived and worked there for a short while. There Anousheh helped do experiments and later wrote a book about her amazing journey. 

Chris Hadfield

One of the most well-known astronauts to live on the ISS is Chris Hadfield. Chris was born in Ontario, Canada. He grew up on a farm with his family where they grew corn. When Chris was little he became interested in flying and later saw the Apollo 11 moon mission, which made him want to be an astronaut like Neil Armstrong. Later, he went to college, then joined the Canadian Air Force. This eventually led to training as an astronaut for the Canadian Space Agency and working on the International Space Station. On the ISS Chris shared his day-to-day activities on Twitter and Facebook and later made a music video on YouTube while playing the guitar in space! This brought even more attention to the important work they were doing on the ISS. 

Records

Many records have been set by the crew of the ISS — such as most consecutive days in space by an American, which was 340 days by astronaut Scott Kelly. The other cool thing about Scott’s trip to the ISS is he is a twin, so they were able to study how space affected Scott versus his twin brother who stayed on Earth. 

Another record was the longest spaceflight by a woman at 289 days by Peggy Whitson. 

The ISS also holds the record for most people in space at once, which was a crew of 13 in 2009.

How do you see the space station?

Did you know you can see the space station from earth? With the help of your parents, if you go to spotthestation.nasa.gov you can sign up to receive text messages or emails whenever the space station is visible above you. Recently, my kids and I did this and it was amazing to see it float across the night sky like a star. 

It Takes Teamwork!

One of the best lessons we can learn from the International Space Station is that by working together people all over the world can do amazing things. Isn’t this so much better than focusing on our differences and fighting? One problem in the world is when people look at those who are different and think there is something wrong with them because they aren’t the same. But differences are what keep the world interesting and there is so much we can learn from each other, from our different experiences and customs, and beliefs. The space station shows that even though we have differences we have common goals, like visiting space and learning about space and the Earth. As we focus on what is common, we can work together to do great things. 

Conclusion

A couple of years ago I worked with a man from India. I’d never met someone from India, so it was very interesting listening to his homeland, what it was like to grow up in India, and his different beliefs. He celebrated different holidays and had different ideas about the world, but it fascinated me to try and see the world through his eyes. As we got to know each other we became friends and I look back on our talks with fondness.

Take a moment to think of someone you know who is different than you. They might be from a different country, look different, talk differently or act in a different way. Take the leap and ask them a few questions and try to get to know them better — because chances are you’ll learn something interesting and possibly make a new friend in the process!

Recommended Books

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Sometimes, siblings end up leading very different lives. And sometimes, they end up needing each other more than they realize, even when they’re grown up.

Birth of William and Caroline Herschel 

William and Caroline Herschel were born into the same family, but their opportunities in life were very different. Born in Hanover, Germany in the early eighteenth century, William was 12 years older than Caroline. At the time, as you might guess, girls were expected to learn how to run households and get married. But it wasn’t just the fact that Caroline was a girl that limited her opportunities. She was also sick a lot as a child. A bout of smallpox at age four left her face scarred. At 10, she suffered a typhus infection, which stunted her growth: she only grew to a height of 4 foot 3.

All this misfortune left Caroline’s mother, Anna, sure that her youngest daughter would never be able to marry.  Anna didn’t approve of girls being educated either. That left housework. She decided Caroline would become a servant, and promptly began treating her like one. 

While Caroline learned to cook and mend stockings, her brothers went to school and learned to play musical instruments. Their father, Isaac Herschel was a member of a military band. Though he was often away from home, he didn’t share his wife’s views on education for girls. When he did come home, he would always find time to teach Caroline alongside her brothers.  He even took her out one chilly evening to show her the stars and a comet.  So she did end up with a basic education.

With her ability to read and write, Caroline helped her mother, who couldn’t do either, write letters to her father when he was away. Other military wives in their neighborhood also took advantage of her skills. Whenever she found a spare moment without any chores, she made the most of it by reading or playing the violin.

Still, Caroline felt lost and forgotten in her large family. But William always seemed to notice her and stand up for her. After their father died, he suggested that Caroline come and live with him and their brother Alexander in England. He was working as a musician in the city of Bath, and thought he might be able to train Caroline to sing in his performances. William played several instruments – violin, harpsichord, oboe- and also wrote songs and symphonies. 

Caroline had looked around for years, trying to find something other than the dull drudgery of housework she could do to support herself. She had learned how to knit and make frilly dresses and fancy hats, but her mother insisted she only do these things for family members. She had hoped to learn French so she could become a governess, caring for a wealthy family’s children. Her mother forbade it. Singing for her brother sounded like the perfect escape! William made a deal with his mother: He would pay for a servant to replace Caroline, and she would come to England to train as a singer. 

Astronomy: A New Hobby

So Caroline finally left her dreary life as the family servant behind at the age of 22. On their journey to England, she and William rode on top of their carriage at night, and he re-introduced her to the hobby their father had shared all those years ago: astronomy. William pointed out stars and constellations and told her about the telescopes he used to view them at home. They stopped at optician’s shops in London where William scoured the supply of mirrors and lenses for ones he might use to build new telescopes. 

When they arrived in Bath, things didn’t go as Caroline hoped, at least not immediately. She was frustrated to learn that she would still have to do most of the housework for her brothers. But in addition to the housework, she was learning and improving herself every day. William began tutoring her in math, bookkeeping, English, and, of course, singing. 

Caroline took two or three singing lessons each day and soon began to perform in public. After a few years, she had become famous in Bath! She got offers to sing in festivals, but she insisted on only performing when William was conducting. 

In the meantime, William was becoming more and more obsessed with his astronomy hobby. He’d stay up late, observing stars, and tell Caroline what he’d seen in the morning. Soon, Caroline became William’s astronomy assistant as well. He built a tall platform to observe from. He would yell down the positions of stars and nebulae and other celestial objects, and Caroline would record them carefully in her notebooks. Even on the coldest nights, they bundled up so they could keep watching the sky. 

Soon, Caroline was learning more advanced geometry and algebra so she could measure the distances and angles between celestial objects. She began making her own observations of the night sky. The siblings recorded every object they saw as they gazed up into the cold, dark heavens. 

Building a New Telescope

But William wasn’t satisfied with the tools he had at hand. Telescopes at the time didn’t magnify as much as he would have liked. They used small concave mirrors–think of a shallow bowl–to gather light from far off in space, then that image reflected onto another small, flat mirror that the observer looked at. But these mirrors were only a few inches across, and bigger mirrors would mean more magnification. But no one knew how to make a larger mirror that was still clear and smooth enough to create a sharp image. 

William bought his own equipment and began experimenting with creating his own mirrors. At first, Caroline was mostly responsible for making sure William had food to eat while he labored long hours on his mirrors. But soon, she began to help grind and polish the mirrors as well. It was smelly, messy work– they created molds for their mirrors out of horse poo– but after some practice, William created a better mirror: 6 inches across, polished to a perfect, smooth, uniform surface. He mounted it in a 5-foot-long telescope tube. Later, he created an even bigger mirror and built a 20-foot telescope! 

New Discoveries for William and Caroline Herschel

With their new instruments, the pair racked up thousands of discoveries. William realized that many bright stars were actually two stars that were so close together that they appeared to be one unless you looked at them through a powerful telescope. Likewise, some fuzzy objects that people once thought were nebulae turned out to be clusters of stars. Caroline discovered eight comets and thousands of new nebulae and star clusters using the better telescopes. 

In 1781, William made his most exciting discovery yet. He noticed a fuzzy object in the sky that looked a bit like a comet. But it didn’t behave like a comet. After watching it for weeks and calculating its orbit, he realized it was a planet! No one had discovered a new planet since ancient times. William decided to name the planet Georgium Sidus, or George’s Star, after the current king of England, King George the Third.

The Royal Astronomer

The name didn’t stick–eventually another scientist renamed it Uranus, after a Greek god. But King George didn’t let the compliment go unrewarded. He asked William to become the royal astronomer! William accepted, and he and Caroline moved closer to the palace. 

William even requested that Caroline be paid a salary, and King George agreed. Not only could Caroline now support herself–something she’d longed for her entire life–she also became the first woman to be paid for doing science! 

Working for the king allowed the Herschels to take on even bigger, more ambitious projects. King George gave William the money to build what would be the largest telescope ever constructed. It would have a 4-foot, one-thousand-pound mirror and be over forty feet long! That’s about the length of ten Caroline Hershcels! The telescope would have to sit on a specially designed rotating platform and would be supported by an elaborate system of scaffolding. It took 5 years to build. When it was done, they threw a party, with guests dancing in and out of the tube before it was put in place. 

William married in 1786, but unfortunately, Caroline didn’t get along with his new wife at first. After spending her entire adult life by her brother’s side, Caroline had to move out on her own as William’s wife took over running his household. But eventually, the two women seem to have mended their relations, and Caroline wrote about her in friendly terms in later journals. She became a role model and educator for their son, John, shaping him into a first-rate astronomer in his own right. 

Caroline kept herself busy with her own astronomical projects as well. She created a catalog of all known stars. An astronomer named John Flamsteed had created a catalog years earlier, but Caroline’s would correct many errors and add more than 500 new stars. The Royal Astronomical Society in London published her work in 1798. 

Royal Astronomical Society

William passed away in 1822. Caroline was devastated by the loss of her brother, but kept on studying the night sky, carefully recording every detail. She and William’s son, John, worked together to catalog their observations. Eventually, she moved back to Germany. She was famous and respected for her work. The Royal Astronomical Society in London and the King of Prussia–now part of Germany–presented her with gold medals. She lived until the age of 97, and died peacefully in her sleep in her hometown of Hanover.  

Together, William and Caroline discovered over 2,000 objects in space – asteroids, comets, nebulae, and star clusters. William’s gravestone has the Latin words Coelorum perrupit claustra engraved on it–”He broke through the barriers of the heavens.” Not only did he break through the barriers of the heavens, he made sure his sister was able to break through with him. Caroline saw that knowledge could help her leave behind a life of drudgery and housework if only someone would share it with her. William saw that his sister was smart and capable, and refused to let her talents go to waste. 

Together, William and Caroline changed how people viewed the universe, and opened many eyes to its wonders. And together, these siblings did more than either one could do alone!

Sources

https://www.sciencehistory.org/distillations/magazine/a-giant-of-astronomy

https://scientificwomen.net/women/herschel-caroline-43

https://www.space.com/18704-who-discovered-uranus.html

http://digital.library.upenn.edu/women/herschel/memoir/memoir.html 

Krull, Kathleen (2013) Lives of the Scientists: Experiments, Explosions (and what the Neighbors Thought). Houghton Mifflin Harcourt, New York.

The post History of William and Caroline Herschel for Kids appeared first on Bedtime History: Podcast and Videos For Kids.

Have you ever wondered what makes a rainbow? This is a question that many children wonder about, and now, most parents have a ready answer (though some might encourage you to guess anyways!). But in the past, people didn’t know how these beautiful arcs of color formed in the sky. Some people were curious enough to ask why, but until the 1600s, no one did much more than make thoughtful guesses. It would take a mind nearly as bright as the sun to solve that and many other mysteries of how nature works. His discoveries paved the way for the modern fields of physics, astronomy, and math.

Early Life of Isaac Newton 

The person who discovered what makes a rainbow was born into a rather dull world. Isaac Newton’s story begins on a sheep farm surrounded by apple orchards in rural England on Christmas day in 1642. Born prematurely to a poor family, no one expected the sickly infant to survive, but he did! Unfortunately, his father wasn’t so lucky. While little Isaac would live to be 84 years old, his father died three months before he was born. Isaac’s mother remarried to a well-off minister when he was two years old. Isaac never liked his stepfather and lived with his grandparents for much of his early childhood.

Isaac’s mind was so bright and active that he needed little else to hold his interest in the quiet hamlet where he lived. He wanted to know how the world worked and found all kinds of questions to occupy his mind. His mother, however, didn’t see much value in education, and after sending him to school briefly, pulled him out and tried to get him to help with the farm work. Isaac hated farm work–it kept him from exploring the many big questions about the world that flooded his head. Fortunately, Isaac’s uncle and his teacher both saw what a brilliant intellect he possessed. Seeing how poorly Isaac performed as a farmhand, his mother eventually took their advice and sent her son back to school. 

Isaac flourished in school, where he studied Latin, Greek, and mathematics. When he had learned all he could at the local school, he headed off to Cambridge University. He mostly ignored his fellow students, even his roommate, and spent most of his time alone in his room. There he could let his mind play– with the ideas of the ancient philosophers, the observations of famous astronomers, and complicated mathematical formulae. His books, his quill pen, and the shadows creeping across the walls seemed to be the only company he needed as he delved into these subjects in a search for truth. 

After graduating from Cambridge, Isaac returned home for two years. An outbreak of bubonic plague was sweeping England, and he felt it was best to isolate himself. This also suited Isaac’s preferences. He finally had an excuse to spend all his time alone in his studies, and he took full advantage. He spent his days reading, calculating, and setting up experiments.

Isaac Newton’s Experiments

Some of Isaac’s experiments didn’t work out. He tried to concoct a cure for the plague using rose water and turpentine, but it didn’t work. He also dabbled in alchemy, attempting to create gold from other, non-precious materials, a hobby he would come back to many times over his life. We now know this is impossible, but many people at the time thought it could be done.

Isaac’s experiments with light had better outcomes. He was fascinated by prisms, crystals shaped like triangles that create rainbows when light shines through them. Isaac was curious why this happened. Most people at the time thought that prisms somehow “corrupted” white light, adding in the colors of the rainbow, but Isaac suspected this wasn’t true. His experiments led him to the conclusion that plain white light from the sun was actually made up of all these different colors, and the prism split them apart. 

In one experiment, Isaac set up three prisms in a row so that light from a window would shine through them, but their rainbow colors would overlap on the edges. Where the broken-up light from different prisms overlapped, the wall was white! The colors had mixed again into white light! He also lined up two prisms, putting a wall with a hole between them. He set up the first prism so that only the red light from the rainbow hit the hole in the wall and went on to hit the second prism. The red light passed through the second prism, hitting another wall beyond. This light couldn’t be broken up anymore, and of course, the second prism didn’t “add” colors to it, which should have happened if prisms worked the way other people thought. If Isaac rotated the first prism slightly, he could direct the blue, or yellow, or orange light to pass through the hole and onto the second prism. With each color he tried, the light hit at a different point on the final wall after passing through the second prism! Each color bent at its own special angle when it passed through the prism. 

These were simple experiments–you could even ask your parents to buy some inexpensive prisms and try them yourself. Some of his experiments I wouldn’t recommend trying at home. He also tried to find out if he could see the rainbow colors of light by pushing on the back of his eyeball with a long, blunt sewing needle. Again, don’t try this at home! Still, Isaac’s unique mind let him imagine new ways to explore how light really worked instead of just believing what others had said before. 

But, if you’ve heard one story about Isaac Newton before now, it’s probably about how he discovered gravity. That story recounts how an apple fell on his head and led him to the idea that there was a special force called gravity. This is also the story that Isaac liked to tell about the discovery! Gravity, Isaac theorized, is the force that makes larger objects, like the earth, pull smaller objects, like you and me and the apple, toward them. All objects, even very small ones, have gravity, but small objects only have a tiny bit compared to something as massive as the Earth. Isaac realized that gravity could explain not only the apple falling from the tree, but also the orbits of the moon and planets.

The idea of gravity led Isaac to think in new ways about how objects move. He experimented with motion and force, and formulated his three famous laws of motion based on these experiments. The first law was that if an object is at rest, or standing still, it would stay that way unless something came along and pushed or pulled it. Likewise, if an object was moving, it would keep moving in a straight line unless, again, something pushed or pulled it to make it stop. These pushes and pulls are called “forces.” The second law says that how much an object speeds up has to do with both how strong of a force is applied and how heavy the object is. Finally, his third law says that for every action, there is an equal and opposite reaction. In other words, forces come in pairs. Imagine you and a friend are ice skating. If you face each other, put your palms together, and push, both of you will be propelled backward. If you’re about the same size, both of you will go about the same distance. But if one of you is much bigger, the smaller person will go back farther and faster. 

Newton’s Explorations in Mathematics

Isaac also worked out the math that explained his laws. Some of this math was fairly simple, but when it came to explaining gravity and the orbits of planets things got complicated. In fact, he developed a new branch of math called calculus to explain what he was seeing. Calculus is a kind of math used to describe things that are continuously changing, getting faster and slower. Think of the curve that a ball follows through the air when you throw it, or how fast a rocket is going at any given time as it blasts into space. These actions involve motions and forces and objects that are different weights and sizes. They get faster or slow down at different times. Very complicated! 

Isaac Newton didn’t share his discoveries about calculus for a long time. He didn’t enjoy the attention his big discoveries brought him, and may have wanted to avoid it. He just wanted to discover the truth about how the universe worked. When he finally did tell people about it, another mathematician named Gottfried Leibniz had also come up with the same kind of math!  Newton and Leibniz would both argue that they were first, but it didn’t really matter. Both were very smart and had come up with the ideas on their own. 

After the plague died down, Isaac returned to Cambridge and became professor. He continued to spend most of his time studying and experimenting. He often ignored his own needs while deep in thought and study. He’d stay up late at night thinking, writing and experimenting. When he did sleep, he usually didn’t change into pajamas, and he went days without combing his hair. He ate simple meals of porridge or milk and eggs, and at times ate only foods from vegetables. 

Isaac Newton’s Later Life

As Isaac got older, he began to take on some new and unexpected responsibilities. He was chosen to represent Cambridge University in Parliament, which is part of the government. True to his introverted nature, he rarely spoke up in debates. Later, he was chosen to run the Royal Mint, which was the part of the government that made money. 

Isaac liked the capital, London, and moved there. Although he was never on good terms with his half-siblings from his mother’s second marriage, it seems he liked his nieces and nephews. He lived with his niece, Catherine Barton for many years, and left his papers and journals to her. He split the rest of his belongings between all his nieces and nephews.

Isaac Newton once wrote that truth was his greatest friend. Few people–if any–have contributed as much to scientific discovery as he did. We’ve only touched the surface of all his accomplishments. His work in calculus and physics launched an entirely new era in science. He set an example for future scientists by carefully designing experiments to answer very specific questions. His laws of motion helped later scientists send people to space on rockets and return them to Earth safely. He scrutinized the natural world and challenged assumptions about how things worked. The truth was his greatest friend, but he also proved himself a great friend to truth. 

Sources

https://www.coolkidfacts.com/laws-of-motion/

https://en.wikipedia.org/wiki/Isaac_Newton

https://www.wondriumdaily.com/the-discovery-of-gravity-and-laws-of-motion-by-isaac-newton/

Krull, Kathleen (2013) Lives of the Scientists: Experiments, Explosions (and what the Neighbors Thought). Houghton Mifflin Harcourt, New York.

The post History of Isaac Newton for Kids appeared first on Bedtime History: Podcast and Videos For Kids.

Everyone spends time learning what they like, and what they’re capable of. Sometimes, they learn that what they are capable of isn’t what they like, and something else is calling them. That happened to Sally Ride.

Early Years of Sally Ride

Before we can get to what happened though, let’s go back to Southern California in the year 1951. This was the year Sally was born to Dale and Carol Ride. As a child, Sally’s dream job was to play baseball for the Los Angeles Dodgers. She was athletic, and was often chosen first for baseball teams. Of course, no women played major league baseball at the time, but this didn’t matter to Sally. Dale and Carol raised her and her sister, who was nicknamed Bear, to explore and try anything that interested them. To Sally, this meant playing sports and stargazing through a telescope with her father. Her favorite constellation was Orion. Many people in the 1950s thought of these as “boy” things, but Sally knew they were also girl things.

Sally Ride and Tennis

When she was nine, Sally’s family traveled to Europe. Between seeing the amazing sites, Sally played tennis for the first time on the trip. Just like that, Sally was hooked. Tennis became the center of her life. When they got back to the United States, Dale and Carol got Sally a tennis coach and she began competing. Before long, she was ranked in the top 20 players under 12 in Southern California! 

Tennis also opened doors for Sally. A private high school gave her a scholarship to play for their team. In high school, Sally rediscovered her love of science. One teacher, Dr. Elizabeth Mommaerts, helped her see that there were opportunities for her in science. At the time, there weren’t many women who got advanced degrees in science, but Dr. Mommaerts had a PhD in human physiology. Sally was amazed by how smart and curious her teacher was, and how she approached every problem carefully and methodically, like a puzzle. 

After high school, tennis again helped Sally find a place at school. She headed to Swarthmore College to study physics and play on the tennis team. Soon after arriving though, Sally’s mind began to wander to new possibilities. She was excelling at tennis: she won all her college matches, and even became the Eastern Intercollegiate Women’s Singles champion! Sally decided she wanted to try to become a professional tennis player. She packed up her bags and left Pennsylvania to return to Southern California. 

Back in sunny California, Sally practiced every day for hours, year-round. But soon, she realized that she’d need to train even more in order to make it as a pro. Her body ached. She was tired. Playing tennis wasn’t as fun when she had to do it eight hours a day in order to compete. Sally decided to return to college full time. 

Collegiate Life of Sally Ride

Sally headed to Stanford University, about a six hour drive from Los Angeles. There, she reacquainted herself with her other childhood passion: science. She studied physics: how stars and planets work, and even lasers! 

This time, Sally was sure she’d made the right choice about her future. In fact, she stayed at Stanford an extra five years to earn her PhD in physics. 

But even as Sally focused more on physics, she was still open to new opportunities. One morning in 1977, shortly before she finished her PhD, a huge opportunity stared her in the face when she opened her morning paper. It was the kind of opportunity that made all her past hobbies and interests fall into place. Even though she never could have known this opportunity would come along, it was perfect for Sally’s background as a sports-loving physicist. 

It was an ad. NASA was recruiting new astronauts to fly in the space shuttle program. And for the first time, they were accepting applications from women. Sally had expected to get a job as a college teacher. But the chance to be an astronaut doesn’t come along every day, and Sally was excited by the possibility of actually visiting space, after studying the stars and planets and gazing up at Orion on so many nights. And, astronauts need to be in great physical shape too. All her years of playing tennis would be an advantage too. 

NASA was a bit overdue in sending women to space. In fact, all the astronauts until this time had been white men, mostly Air Force pilots. Russia had sent a woman to space in 1963! Now, in addition to recruiting pilots, NASA was opening the astronaut program to anyone with training in science or engineering.  They got thousands of applications! Out of all those applicants, Sally and five other women were chosen to train as astronauts! Not only were the first women chosen to be part of the space shuttle program, the class of 35 men and women included the first Asian American and African American astronauts.

Sally at NASA

Sally began her training in 1979. NASA was impressed by Sally. She was athletic and strong, committed and smart. Years of playing competitive tennis had taught her how to keep cool under pressure. 

But even though Sally had the right stuff to be an astronaut, there was a lot to learn! She had to know space shuttle systems inside and out. She learned about geology, oceanography, and computer science, since she would need to perform all sorts of experiments in space. The astronaut candidates learned to fly supersonic jets, though most of them wouldn’t actually need to fly the shuttle–NASA still used professional pilots for that–it was important to know how it worked in case there was ever an emergency. 

Off to Space for Sally Ride!

Finally, in 1982, after years of training and working on projects and shuttle missions from the ground, Sally got the call that all astronauts are eager for. NASA had assigned her to a mission. She would go to space in 1983 as a mission specialist on the space shuttle Challenger. 

Sally would have a whole year to prepare for the mission. As part of her work on the ground for NASA, Sally had helped design a robotic arm that would move things like satellites in and out of the space shuttle’s cargo bay. On her mission, Sally would use the arm to place a satellite outside in space. It would fly alongside the shuttle for a few hours, taking pictures and doing experiments. Then, Sally would use the robotic arm to grab the satellite and pull it back into the shuttle.

It was an exciting project for Sally, but she was disappointed to find that news reporters weren’t very interested in it. Instead, they always asked her questions about what it would be like for a woman in space. Would she wear makeup in space? Would she be able to have children after going into space? Would she cry if she made a mistake? Understandably, Sally found these questions annoying at best, even insulting. Why couldn’t reporters ask her about the actual mission–the science she’d be doing, or the amazing robotic arm she’d designed–instead of obsessing over her gender? 

But Sally kept her focus on training and ignored the rude questions. She made sure she knew every step of every task she needed to do during launch, in space, and on landing. On June 18th, 1983, Sally was ready to lift off! 

The mission was a success: the crew performed experiments, and the robotic arm worked beautifully. But besides conducting experiments and gaining experience in space, Sally realized something far more profound. As she looked out the space shuttle window for the first time, she noticed something that astonished her: 

“…it looked as if someone had taken a royal blue crayon and just traced along the Earth’s horizon. And then I realized that that blue line, that really thin royal blue line, was Earth’s atmosphere, and that was all there was of it. And it’s so clear from that perspective how fragile our existence is.” 

Challenger Mission

Sally flew on another mission two years later, again on Challenger. Sally hoped she’d be able to fly again after her second mission, but in 1986 a terrible tragedy threw her hopes, and the whole shuttle program, into doubt. The space shuttle Challenger, which Sally had flown on twice, exploded a few minutes after lift-off. Seven astronauts were killed, including some Sally had trained with. Sally was devastated, but she was also one of the best people to help figure out what went wrong. NASA canceled all its space shuttle missions for years while Sally and a committee of other experts investigated the accident. They found that cold weather that morning in Florida caused a part to break during the flight. 

By this time, Sally realized she would probably never fly on another mission. She stayed at NASA another year after the investigation, helping them plan for the future. But in 1987, she realized it was time to leave. 

Sally went back to Stanford University to work as a physics professor. She also reconnected with a childhood friend, Tam O’Shaugnessy. The two fell in love, and would spend the next 27 years together. Tam was also a scientist–a biologist–and she loved sports and exercise too. Sally and Tam also shared a passion for encouraging children, especially girls, to explore science and technology. They wrote books and started a foundation together that offered science summer camps and science festivals. Sally even started a program that let kids in middle school control a satellite launched into space on the shuttle, taking pictures of earth from hundreds of miles above the ground. 

Sally’s Death

In 2011, Sally learned she had pancreatic cancer. After battling the disease for over a year, she passed away at home in California. A year later, President Obama awarded Sally a Presidential Medal of Honor for her accomplishments. Tam accepted the award on her behalf.

People change their minds sometimes about what they want to do. New dreams take hold. But the most important thing to do if you want to make a dream come true is to act. Find out what you need to do to actually make that dream a reality and do it! You may find that you don’t like the doing as much as the dream, just like Sally Ride did with pro tennis. But, like Sally, if you try enough things, eventually you’ll find the right thing for you. And you never know when an opportunity will come along that requires your unique combination of talents, skills, and knowledge. So keep exploring!

Sources

https://rvsallyride.ucsd.edu/legacy/

https://en.wikipedia.org/wiki/Sally_Ride

Abawi, Atia (2021) She Persisted: Sally Ride. Philomel Books, New York.

Macy, Sue (2014) Sally Ride: Life on a Mission. Aladdin, New York.

The post History of Sally Ride for Kids appeared first on Bedtime History: Podcast and Videos For Kids.

Have you ever seen the word “pasteurized” on a carton of milk? You might think it means something about pastures – big grassy fields where animals graze. That’s usually how people pronounce it. But while it’s nice to think of the cows that gave us the milk sunning themselves in grassy pastures, the word actually refers to something that happens after the milk is out of the cow. Before milk goes into cartons and then on to the store, it undergoes pasteurization. The milk is heated to a specific temperature in order to kill any harmful microorganisms, or germs, that might make you sick. It has nothing to do with grassy fields! Instead, it’s named after the man who invented the process: Louis Pasteur.  

Educational Background of Louis Pasteur

Louis Pasteur’s background gave no hint that he would become a great scientist later in life. Born in 1822 in Dole, France, he came from a long line of leather tanners. His family was poor, and Louis wasn’t even that interested in school as a child. He preferred fishing and drawing. He actually became very good at drawing portraits of his friends and family using pastels and pencil.

Things began to change when Louis went off to college. He began to study hard, but still struggled. His grades in chemistry – a subject he would later do important work in– were especially bad. He wanted to go to the prestigious Ecole Normale Superieure in Paris, but had to take the entrance exam twice! But even though he had setbacks, his hard work and dedication paid off. 

While he was working to try to get into the Ecole Normale, Louis began attending lectures by a famous chemist, and decided that he wanted to be a chemist too. So, when he finally went to the Ecole Normale, that’s what he studied. After he got his doctoral degree, he got a job at the University of Strasbourg, teaching and doing research in the structure of chemical crystals. 

He also met his wife, Marie, there. She was the daughter of the head of the university. At first, she wasn’t so sure about this serious, somewhat shy man. But after getting to know him better, she fell in love too, and they married. She would support him throughout their lives together, helping in the lab and with his papers. 

Louis Pasteur’s Early Works

Even though Louis started out as a chemist, his most important work is in microbiology, or the study of organisms so small, you need a microscope to see them. This shift happened almost by accident, but as Louis himself reminded people, “In the fields of observation, chance favors the prepared mind.” In 1854, he got a new job at a university in northern France. While there, the owner of a factory came to him with a problem. His factory fermented sugar beets to make alcohol, but sometimes he ended up with a spoiled, sour elixir, instead of alcohol.  

At this time, scientists didn’t know how fermentation worked. Some thought it was just chemicals rearranging themselves spontaneously under the right conditions. Most people just knew that when you left crushed grapes or soggy grain in a covered container for long enough, you got wine or beer. Louis wasn’t satisfied with those answers though, and set about trying to solve the mystery. He got samples of the good alcohol and the sour substance and put them under his microscope. 

What do you think he saw?

He saw different kinds of microorganisms swimming around in them! The alcohol samples had yeast, which is a microscopic type of fungus. The sour stuff had bacteria, which is a completely different kind of microorganism! Both types float around in the air, but Louis was the first to realize that the yeast settled in containers of grapes or mashed grain and caused fermentation. Those tiny yeast ate up the sugars in the beets, used it to make energy, then got rid of the uhhh…waste that they didn’t need. That waste was the alcohol.

Studies in Microorganisms

Louis was hooked. He went on to study the microorganisms in wine and beer, finding new ways to make sure they weren’t contaminated by tiny critters that would spoil them. But he wasn’t just interested in making beverages safer, although this was very important for people’s health and the French economy. Louis wanted to know more about how these tiny microorganisms lived. If so many scientists were wrong about fermentation, what other discoveries were waiting to be made?

One idea that didn’t make much sense to Louis was “spontaneous generation.” Spontaneous generation was the idea that some living creatures just arose from nonliving things. Rotting meat made flies, some people thought, because they’d seen fly larvae on rotting meat. Louis thought that flies must be laying tiny eggs in the meat. He suspected that microorganisms, like the yeast in beer and wine, actually float around in the air, settling on things and, if the conditions are right, growing and multiplying.

Louis devised an ingenious way to demonstrate that living things didn’t just spring fully-formed from non-living things. He designed a bottle with a long, skinny neck that curved downward like the top of the letter S, opening toward the ground. He then boiled a broth, killing any microorganisms that were already in it. He poured some of the broth into the S-neck bottles, and some into bottles with necks that opened upwards, toward the sky. 

Then he waited. After a few weeks, the bottles with the S-necks hadn’t really changed. But the ones with upward-facing necks had become cloudy. Looking at the liquid under a microscope confirmed that microorganisms had landed from the air and grown in it. But, microorganisms couldn’t land in the S-neck bottles, so that liquid stayed clear!

With all these accomplishments and discoveries to his name, you might be wondering, what else can one scientist do? A lot, it turns out! Louis wanted to study how microorganisms might be involved in causing diseases, and maybe even find ways to prevent or cure those diseases.  Sadly, he was motivated by events in his own life: three of his daughters passed away from typhoid fever when they were young. He started studying two diseases caused by bacteria: chicken cholera and anthrax. 

Chicken cholera is not a serious disease for humans, but is deadly to chickens, which you might have guessed from the name. Louis developed a vaccine for it almost by accident, but as with his study of microorganisms in alcohol, he was prepared to take advantage. Before going on vacation Louis gave an assistant specific instructions for how to infect some chickens with the bacteria they had been growing. But the assistant waited too long, and the cholera bacteria dried up. Lucky chickens!

But Louis didn’t think of himself as unlucky. Instead, he decided to give the chickens a dose of the dried-up, mostly-dead bacteria. These chickens got a little sick, but soon recovered. Later, Louis injected those same chickens with fresh, living cholera bacteria. Louis suspected that the first dose of mostly-dead cholera bacteria might actually protect the chickens from the living bacteria. He was right! The chickens didn’t get sick again!

Next, Louis heard about a vaccine for anthrax that a veterinarian named Jean Jaques Henri Toussaint had invented. Anthrax bacteria was deadly to both farm animals and people. He tested Toussaint’s vaccine, and it worked. In an unfair twist, Louis got credit for creating the vaccine, because his test was more widely covered in newspapers at the time. Sadly, Toussaint died only a few years later.

But Louis wasn’t done working on vaccines. The next disease he studied was truly terrifying: rabies. Rabies is a virus that causes animals, and unfortunate humans they might bite, to get a high fever, behave aggressively, fear water, and eventually die. There was no cure. Louis got to work, trying to develop a weaker version of the disease that could be used to make a vaccine. He tested it out on dogs. It seemed to work, but Louis wanted more time to experiment. 

But the experiment was about to speed up. One summer day in 1885, a mother burst into the lab, gripping the hand of her nine year old son. Both were crying and distraught. The boy, Joseph Meister, had been bitten 14 times by a rabid dog. Louis was worried because he had never tried his vaccine on a human. But without help, Joseph would die. Louis had to try. Just as they had done with the dogs, Louis and his assistants injected Joseph with the vaccine several times over the course of weeks. Louis and the boy’s mother spent this time worrying and waiting. It can take weeks or months for a person to get sick with rabies after they’ve been bitten, so they wouldn’t know if the vaccine had worked for some time. 

But time passed, and Joseph stayed healthy! He went back to school and playing outdoors, though I wouldn’t be surprised if he was afraid of dogs after that. People all over the world heard about the new rabies vaccine, and people came from miles away to receive it if they’d been bitten. Today, almost all pet dogs and cats get the rabies vaccine, though humans usually only get it if they’ve been bitten by a wild animal. Louis’s vaccine saved countless lives.

Louis Pasteur always wanted to use his work to serve others. Thanks to his work, we know a lot more about how microorganisms work, how they cause disease, and how to keep from getting sick from them. But Louis knew that wanting to do good wasn’t the same as actually doing it. He worked tirelessly, sometimes pacing the room late at night while he thought through a problem. He was careful and methodical in his work, trying to be sure he’d gotten it right, before he made any exciting announcements. But he also knew when to take advantage of an opportunity. If he didn’t, he never would have studied the yeast in fermented drinks, or how to make vaccines from weakened germs. He never would have saved Joseph Meister’s life with his rabies vaccine. Your milk wouldn’t be as safe to drink. So next time you notice something unexpected, or find something didn’t work the way you thought, think of Louis Pasteur, and keep examining it. Look at it carefully. You might discover something amazing!

Sources

Curtis, Robert H. (1993) Great Lives: Medicine. Macmillan, New York.

Dickman, Nancy (2016) Louis Pasteur: Germ Destroyer. Gareth Stevens Publishing, New York.

https://www.khanacademy.org/science/ap-biology/cellular-energetics/cellular-respiration-ap/a/fermentation-and-anaerobic-respiration

https://www.nature.com/articles/d42859-020-00008-5

https://pubmed.ncbi.nlm.nih.gov/20527335/

http://thispodcastwillkillyou.com/wp-content/uploads/2021/10/TPWKY-Episode-82-Anthrax.pdf

The post History of Louis Pasteur for Kids appeared first on Bedtime History: Podcast and Videos For Kids.

Have you ever wondered why your hair is curly like your mother’s, or you have freckles like your father? Or maybe your parents say you smile like your uncle, who you don’t even see that much. All these things are related to your genes. Genes are the stuff inside your body that tell your cells how to build YOU. You get your genes from your mom and dad, and they got them from their parents. Genes are made out of a substance called DNA, which is short for deoxyribonucleic acid. Don’t worry, you don’t have to remember that!

But, you might also wonder, what exactly does DNA look like? 

Rosalind Franklin wondered about that question too, and as a scientist, she helped answer it. It wasn’t an easy question to answer, because DNA is much, much too small for people to see. Knowing how DNA is put together would help other scientists learn more about how it works, and eventually make all kinds of other medical advances possible. And Franklin did end up discovering what DNA looks like! 

But before we get to that, we need to go back to London, in 1920, where Rosalind Franklin was born. Franklin was part of a well-off Jewish family, who had been involved in politics for a long time. One uncle served in the British government. Another uncle and aunt were activists for women’s voting rights, which Britain granted in 1918. Her mother did charity work, and her father was a banker and a teacher. During World War II, the Franklin family took in Jewish refugee children who had escaped from Europe. 

Rosalind’s obsession wasn’t politics though. She did care about people, but she was fascinated by science. As a child, Rosalind’s aunt described her as “alarmingly clever–she spends all her time doing arithmetic for pleasure, and invariably gets her sums right.” Rosalind didn’t really spend every moment of her childhood doing math. She was good at most other subjects too. She learned German, French and Latin, but did not do well in music!  Even though she was an excellent student, she also enjoyed sports, travel, and hiking.  But by the time Rosalind was a teenager, she knew that she wanted to be a scientist. She realized that this, too, could be a way to help people.

When it was time to go to college, Rosalind won a scholarship to pay for it. Since she didn’t really need it, she decided to donate her scholarship to a deserving refugee student.  Because of World War II, many people were trying to escape Europe. Many came to England, and did not have much when they arrived. A scholarship to go to college would have been a huge gift.

Franklin studied chemistry at Newnham College, a women’s college that is part of Cambridge University. After she finished her studies, she worked in a lab at Cambridge, but didn’t feel she was respected there. Also, World War II was still raging, and Franklin hoped to do something to support the war effort. So, she left Cambridge to work at the British Coal Utilization Research Association. Studying coal might sound very boring, but it was actually very important work. Coal was critical to the war effort because it was used in gas masks that soldiers wore. These masks filtered out harmful gasses and particles that might otherwise make them sick. Rosalind made several discoveries that helped improve gas masks.

After the war, a friend helped Franklin get a job in a lab in France. Rosalind loved France – the language, the food, and the people. In her new job, she learned to use X-Ray crystallography, which allows scientists to take pictures of microscopic structures, things far too small to be seen with your eyes, and even too small for most microscopes. She became an expert in using this technology, and it would help in her later work on DNA.

In 1950, a professor named John Randall asked Franklin to build an X-ray crystallography lab at the King’s College in order to study DNA. However, Dr. Randall didn’t inform Maurice Wilkins, a scientist who had also been working on DNA at King’s College, that he had hired Rosalind to be in charge of the lab. This upset Wilkins, who thought he would be in charge. The two did not get off to a good start, and never really got along. 

Even so, Franklin launched into her work in the lab with the help of an assistant named Raymond Gosling. She improved the X-ray camera, which allowed her to take much clearer images of microscopic structures. This would allow her and Gosling to make their  big breakthrough. 

But before we get much further, we need to go back a little and talk about what DNA is and why scientists were so excited about it in the 1950s. 

DNA is the instructions for building you. Not just you, but any plant, animal, or other living thing. You are made of billions of cells that are too tiny to see with your eyes. There are many types of cells, but each one contains a copy of all your DNA. 

Think of each cell in your body as a Lego set. You have lots of pieces that can be used to make different parts of your body. Your cells also have machinery for building those blocks into the parts of your body, like fingernails, muscles, or eyes. DNA is like the instruction booklet: it tells your cellular machinery which blocks to use and how to put them together to make the different parts of your body. 

People knew DNA existed before the 1950s. They’d known about it for almost 100 years, and knew something about the chemicals it was made of. But they didn’t know the details of how those chemical pieces were put together. Remember, the pieces that makeup DNA are WAY too small for anyone to see with their eyes, or even with the microscopes that existed at the time. 

One more important discovery about DNA came just a few years before Franklin began working on it. Remember when we talked about genes in the beginning of the episode? 

They’re how parents pass traits–like brown hair, big feet, or freckles–on to their children. In 1944, a scientist named Oswald Avery first showed that DNA is what makes up genes. Before that, no one was sure what was inside living things that did this. He showed that DNA was that thing, which made people very eager to learn more about it! 

So by the 1950s, several scientists were trying to figure out exactly how DNA was put together. Using her upgraded X-Ray crystallography camera, Franklin and Gosling took a photo of DNA. Taking this photo wasn’t like snapping a picture on your cell phone. It took hours of work and careful planning. Franklin called it Photo 51, and it was the key to understanding how DNA is put together. Photo 51 looks like a circle with an X made of little dashes in the middle. 

But this wasn’t the end of Franklin’s work. Remember, a photo shows something only from one angle. This was going to be kind of like trying to figure out what a building looks like by looking at a picture of its roof. Franklin got to work using the photo and her knowledge of the chemistry of DNA to try to figure out what the whole structure was put together. In a few months, she had worked out that DNA was shaped like a double helix. To imagine what a double helix looks like, picture a rope ladder. You’re holding the ropes on one end and a friend holds the other end. If you twist the ropes on your end, you’ll get a double helix!

Unfortunately, Franklin wouldn’t be the one to show the world what DNA looked like. Maurice Wilkins got a hold of Photo 51 and showed it to his friend James Watson. Pretty soon, Watson and his coworker Francis Crick were using the photo to try to figure out DNA’s structure. They also worked out that it was a double helix. Watson and Crick wrote a paper and quickly published it, just weeks before Rosalind Franklin had planned to publish her own paper.

Franklin didn’t realize that Watson had seen her photo, so she thought they had done all the work and made the discovery on their own. She had also started a new job, and was glad to be out of the tense environment at King’s College. At her new lab, she and her coworkers made important discoveries about a virus that affects plants, called tobacco mosaic virus. Franklin was glad to feel appreciated and respected again.

Rosalind Franklin would never know that her photograph had helped Watson and Crick decipher the structure of DNA. Unfortunately, she passed away of cancer only a few years later. Watson and Crick would go on to win a Nobel Prize for learning the structure of DNA. It’s unfair that Franklin didn’t get the credit she deserved while she was alive, but strangely enough, it was James Watson who eventually revealed her role in the discovery of the double helix, in a book he wrote in 1968. 

Even though she didn’t get credit for her DNA discovery while she was alive, Rosalind Franklin knew she had made important contributions to science. She felt that science was the best way not only to explain life, but to improve the world. She knew that her work on coal, x-ray crystallography, and plant viruses had done this, so she was proud of her work. In the end, Franklin was more concerned with learning and improving lives with science than she was with being first to do something. She spent her life trying to answer important questions, and even though it’s a little late, people do celebrate that now. I hope you pass along what you’ve learned about Rosalind Franklin, so more people can celebrate her achievements!

Sources

Berger, Doreen. “A Biography of the Dark Lady of Notting Hill.” The United Synagogue, Dec. 3, 2014. https://www.theus.org.uk/article/biography-dark-lady-notting-hill 

Borgert-Spaniol, Megan (2018) Rosalind Franklin: unlocking DNA. Abdo Publishing, Minneapolis.

Maddox, Brenda. “The double helix and the ‘wronged heroine.’” Nature 421, 407–408 (2003). https://doi.org/10.1038/nature01399 

Pray, Leslie A. (2008) “Discovery of DNA Structure and Function: Watson and Crick.” Nature Education 1(1):100. https://www.nature.com/scitable/topicpage/discovery-of-dna-structure-and-function-watson-397/ 

Oswald Avery. Wikipedia.  https://en.wikipedia.org/wiki/Oswald_Avery  

Rosalind Franklin. Wikipedia. https://en.wikipedia.org/wiki/Rosalind_Franklin 

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Actually, that’s not quite true. They’re not really stars at all, but meteors, or bits of rock that come from space and fall through the Earth’s atmosphere. They go so fast that they burn up and create that thrilling streak of light as they fall. Usually, the pieces are small, like a pebble, and the streak is about as bright as a normal star. But sometimes, if the rock is bigger, it’s much brighter. If it’s very bright, it’s called a fireball! Most meteors burn up high above the Earth, but about 3 thousand fall all the way to Earth every year. When this happens, it’s called a meteorite.  Most meteorites land in the ocean, so you don’t need to worry about them. 

Occasionally, meteorites have crashed into cars or houses, but it’s extremely rare for one to hit a person. In fact, only one person in recorded history was ever hit by a meteorite. Her name was Ann Hodges, and the only injury she had was a bruise on her leg. She did get into a legal fight with her landlady about which of them owned the rock though. Her neighbor was luckier: he found a piece of the same meteorite, and was able to sell it. He made enough money to buy a car and a house!

People have been noticing meteors and meteorites for thousands of years, and they’ve been around almost since the beginning of our solar system. Some of the earliest recorded observations are from China, over 2,500 years ago! People in ancient China, Korea, and Japan wrote very detailed and accurate descriptions of meteor showers and fireballs.

But of course, people didn’t always know what either thing was. And when people don’t know what something is, you can bet they’ll make up an interesting story to explain it. In Eastern Europe, some cultures believed that meteors were snake-like dragon creatures called zmek or zmey.  These creatures would grow so large as they got older, that the Earth couldn’t hold them anymore, and they would fly up to live among the stars. In Estonia, people used to think meteors were hot stones thrown to Earth by demons.

Many cultures thought meteors were linked to birth and death–either a soul falling to Earth to be born as a new baby, or a person dying somewhere and shooting to heaven. The ancient Romans thought a meteor shower signaled the death of Queen Cleopatra. And of course, some people believe that if you wish on one, your wish will come true!

Some of the first people to try to explain meteors as part of nature, instead of as magical or supernatural, were the Ancient Greeks. The philosopher Aristotle thought that the Earth’s atmosphere contained both air and fire, which would sometimes ignite in an area high in the sky, causing the streaks of light we know as meteors. There really wasn’t any evidence to back this up, but the idea stuck around for centuries because no one really had a better one. 

Meteorites–the meteors that fall all the way to Earth–were even harder for people to explain. In fact, for centuries, many people believed they didn’t really exist, that they were just legends! It is less common for people to actually witness meteorite impacts, so when they were observed, serious scientists and thinkers dismissed them as fakes. After all, rocks seemed no more likely to fall from the sky than milk or wool…both of which people also claimed to have seen falling from the sky. A few scientists speculated that maybe the falling rocks were from volcanoes, but for a long time, very few suspected they might be from beyond Earth. 

Our knowledge of both meteors and meteorites finally began to improve in the 18th century. Edmund Halley, a famous astronomer who discovered an even-more-famous comet, suggested in 1688 that meteors came from space, but later changed his mind. Other scientists around this time explored the idea, measuring the height and speed of meteors and finding they were too high and too fast to have come from Earth’s surface or even atmosphere.  They didn’t manage to convince many people, but they were slowly chipping away at Aristotle’s ideas, which were now over 2,000 years old.

Several scientists working at the end of the 18th and the beginning of the 19th century would finally do the work that convinced the world that meteorites and meteors were both chunks of rock that came from outer space.  In 1791, Ernst Chladni, a German physicist, first heard from a friend about a fireball seen in the sky over Gottingen. Chladni was captivated by the account, and began to research other stories about rocks falling from the sky. Remember, at this time, many people dismissed the idea of rocks falling from the sky as superstition or legend. But Chladni noticed that all the stories shared certain details, even though they happened at very different times and in different places around the world. This made Chladni think that they couldn’t have been made up. They were just too similar.

Chladni wrote about his ideas, saying that he suspected the rocks people had seen were from outside Earth’s atmosphere, or outer space. He even proposed that they were leftover from the process that formed the planets in our solar system, which is true! But people still didn’t believe him–even the friend who told him about the Gottingen fireball was doubtful. 

Still, other scientists began to study these rocks that supposedly fell from the sky. A British chemist named Edward Howard analyzed a meteorite that fell near a cottage in Wold, England. He discovered that it was made out of chemical elements that weren’t often found on Earth’s surface. He also noted that the mysterious falling stones from different parts of the world were made out of the same kinds of substances. 

It wouldn’t be long before another scientist would finally provide enough evidence–and in the right way–-to put any doubts to rest. Jean-Baptiste Biot was a physicist with a sense of adventure. He went on the first hot-air balloon ride done in order to collect scientific data. In 1803, Biot heard about a rain of rocks–over 3,000!–in L’Aigle France, and he went himself to investigate. 

Biot was very thorough in his investigation. He traveled to L’Aigle to find out as much as he could first hand about this reported rock shower. Just like Edward Howard, Biot noticed that these rocks were made out of different minerals than other rocks in the area, and they weren’t like volcanic rocks either. He studied other meteorites and noticed that they all had more in common with each other than with other rocks in the regions where they were found.

Biot, unlike Chladni, also interviewed many eye-witnesses to the fireball and rock shower. Finally, he wrote an exciting piece about the event. This time, both the scientific community and popular media took notice.  He said that his research was motivated “not by jealous rivalry, but by the noble love of truth.” Very moving words, right? Pretty soon, scientists–and the regular people–began to acknowledge that he was right. 

Since the early 19th century, scientists have learned a lot more about meteors and meteor showers. An American scientist named Denison Olmstead observed a meteor shower in November 1833 that he described as “more extensive and magnificent than any similar one hitherto recorded.” Olmstead began to study meteors as a result of this memorable experience. He showed that some meteor showers, including the one he observed, happen on a regular schedule and can be predicted. The one he saw is now called the Leonids meteor shower, and you can see it every November, plus there are several others throughout the year. Olmstead also suggested that these showers are caused by comets. Comets are balls of ice and rock, so when they pass close to the sun, pieces begin to melt and break apart.  If Earth passes through the trail of debris, we get an amazing show of meteors!

If you ever get the chance, you should definitely try to see a meteor shower someday. And now, you’ll be able to appreciate the long history of our relationship with these shooting stars, and just how long and how many people it took to figure out what they really are. You have to stay up late (or wake up very early) and be in a very dark area to get the best show, but the chance to see dozens of meteors in the course of a few hours is worth the trouble! Many websites publish calendars showing when and where you can see them. Until then, you can look out your window for a few minutes each night and appreciate the moon, stars, and planets, and maybe, just maybe, you’ll catch a streak of light in the corner of your eye. Don’t forget to make a wish, just in case!

Sources

Avilin, T. “Meteor Beliefs Project: East European meteor folk-beliefs.” WGN, Journal of the International Meteor Organization, vol. 35, no. 5, p. 113-116 (2007)

Biot, Jean-Baptiste. 1803. Relation d’un voyage fait dans le département de l’Orne, pour constater la réalité d’un météore observé à l’Aigle le 6 floréal an 11. Baudoin impr, University of Lausanne. https://books.google.com/books?id=JPwTAAAAQAAJ&pg=PA3#v=onepage&q&f=false 

Denison Olmstead, “Observations on the Meteors of November 13th, 1833.” The American Journal of Science and the Arts. 18 June 1791-13 May 1859. 

https://docsouth.unc.edu/browse/bios/pn0001301_bio.html

Eschner, Kat. “For the Only Person Ever Hit by a Meteorite, the Real Trouble Began Later.” Smithsonian Magazine, Nov. 30, 2016. https://www.smithsonianmag.com/smart-news/only-person-ever-hit-meteorite-real-trouble-began-later-180961238/ 

Eschner, Kat. “Scientists Didn’t Believe in Meteorites Until 1803.” Smithsonian Magazine, Apr. 26, 2017. https://www.smithsonianmag.com/smart-news/1803-rain-rocks-helped-establish-existence-meteorites-180963017/

MacDonald, Eve. “How Ancient Cultures Explained Comets and Meteors.“ The Conversation, Aug. 7, 2018. https://theconversation.com/how-ancient-cultures-explained-comets-and-meteors-100982

Turner, Bambi. “10 Superstitions about Stars.” How Stuff Works, Apr 16, 2021. https://science.howstuffworks.com/10-superstitions-about-stars.htm

Williams, Iwan P.  “The origin and evolution of meteor showers and meteoroid streams” Astronomy & Geophysics, Volume 52, Issue 2, April 2011, Pages 2.20–2.26, https://doi.org/10.1111/j.1468-4004.2011.52220.x

Jean-Baptist Biot. Wikipedia. https://en.wikipedia.org/wiki/Jean-Baptiste_Biot

Meteors and Meteorites. NASA. https://solarsystem.nasa.gov/asteroids-comets-and-meteors/meteors-and-meteorites/overview/?page=0&per_page=40&order=id+asc&search=&condition_1=meteor_shower%3Abody_type

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