The best sci-fi novels!

 Sci-fi is not fantasy!

 It drives me mad when you see something like 'Lord of the Rings' called 'Sci-Fi'. I love Lord of the Rings but it has nothing to do with science!  This prompted me to write this post today- the best 'actual' science-fiction novels. Novels that are based in science, with science based plots.  

But what I also find slightly annoying is when I read a science-fiction book, the actual 'science' depicted is just not at all possible. That's not to say that I can't enjoy an inaccurate and impossible science fiction novel, but I do find that the best sci-fi books are ones that make you think 'Could that actually happen?', and it's a bit of a let down when the answer is 'Well, no'. 

So in terms of 'best', I'm looking at the most accurate but also the most entertaining. As always, this list is in no particular order.  Also, this list is based on the novels I've read so happy to hear opinions and I may have to update this list in a few months!

First up! 

The Martian by Andy Weir. 

Brilliant book- the film is brilliant too. 

The Martian is the story of an astronaut Mark Watney, who is left stranded on Mars, after a severe storm results in an urgent evacuation of his team and his presumed death. Mark is now left alone on a planet that can not sustain human life. He has some limited supplies, including food, but he has no method of communication. His food and water supplies will eventually run out and as he is thought to be dead, no one back on Earth is coming to get him.  Another mission is not due to land on Mars for another four years. Mark's one hope is to hold out until then... 

Luckily, Mark is a smart and resourceful guy. A good portion of the book is him trying to solve the problems that the planet keeps throwing at him- and it throws a lot of problems! Mark is also a funny and upbeat character. He refuses to give in and his determination and doggedness, as well as his likeable personality makes this book a great read.

Also making this book a great read and justifying its placement on this list is how accurate the science is. Everything that is done in this book is theoretically possible. In one scene, Mark has to work out how to grow potatoes on a barren landscape. The way he ultimately does it is how the real-life astronauts going to Mars will have to do it. He also works out to create water in a scientifically accurate reaction.

Andy Weir is a brilliant sci-fi writer. His other two novels- Artemis and Project Hail Mary are also fantastically entertaining and wonderfully scientifically plausible. As well as making likeable and brilliant characters and storylines, he has a real talent for making complex science understandable and entertaining for all audiences.  

Next, The Three Body Problem by Liu Cixin. 

Currently reading this one now and I do have to admit, it's a bit of a hard book to get into at first, but there's this sense that things will quickly get interesting and very absorbing. 

The book starts off in the Cultural Revolution of China. An astrophysicist Ye Wenjie is sent to a labour camp but recruited to a secret military outpost that is attempting to find and communicate with extra-terrestrial life. Meanwhile, more than four decades later,  physicists are facing evidence that the laws of physics are not the same everywhere, and a virtual reality video game is forcing players to think of a solution to the 'Three Body Problem'. Earth starts to erupt into chaos as the possibility of alien life begins to become real. 

The book revolves around a solar system that is discovered to have three suns. This links to the Three-Body Problem, a conundrum in astrophysics. It links to the Universal Law of Gravitation, a law that describes the gravitational forces that two bodies- such as the Earth or Sun, exert on each other. That makes it possible to predict the orbits of these two bodies.  These orbits cannot be predicted accurately for three-body systems, and make the whole system unstable. In these systems, it is impossible to know whether the sun will swallow the planet up or the planet will leave the system. 

Whilst the plot initially sounds a little repetitive and overdone, Liu Cixin's attention to scientific details may make this book one of the best sci-fi novels ever written. The depictions of stellar evolution (the life cycle of stats) and interstellar communication, such as using large radio telescopes are accurate. Even his speculative science is theoretically possible- although I can't go into too much detail about this otherwise it will give the plot away!

Third on the list is The War of the Worlds by HG Wells.

Okay, so the science depicted in this reflects what was known at the time, although some of it is pure speculative. It's a little outdated now, being published in 1898 but it's still a brilliant read. 

In the early 20th century, the unnamed narrator is forced to flee his home in Sussex after Martians launch an invasion of Earth.  Earth's defences are quickly outmatched and the narrator is left wandering a shattered landscape, whilst remaining undetected by the Martians. The Martians are shown to be clever and bloodthirsty (literally), being able to create fighting machines, and heat rays that incinerate anyone who tries to oppose them.  Resistance soon collapses and the Martians roam England unopposed. 

At the time of writing this novel, it was believed that Mars was cold, dry and inhospitable. This is true, only we do now know Mars may once have had water. There is not and never was any evidence of Martians then or now. Heat-rays -or energy-directed weapons are however possible. The discovery of lasers in 1960 shows this.  The Martians also use airborne toxins as weapons, something that is very possible.

HG Wells is a brilliant writer and the book is so absorbing. The ending is so very clever and is also scientifically possible. In fact, its the most scientifically accurate aspect of the book and still holds up more than a hundred years late It almost seems anti-climatic but its unexpectedness over-rides this feeling. I think it also reminds you of how much humanity ultimately owes to smaller, simpler life forms...

Next up we have Klara and the Sun by Kazuo Ishiguro.

This book is so sad but poignant and very possible. It revolves around Klara, a solar-powered 'Artificial Friend' (AF). In this future Earth, children are genetically 'lifted' to give them increased intelligence. Schooling is conducted online though screens, and as this gives limited socialisation, children are brought AFs as companions. Klara is given to Josie, a 14 year old who has an unspecified chronic condition. It's established that 'lifting' carries risk.  Klara is incredibly intelligent and observant, but has limited understanding of the world and human nature. As a solar-powered AF, she gains a unwavering faith in the sun, which prompts her to carry out a daring act, in an attempt to help Josie. 

The online schooling carried out though screens gives flashbacks of the COVID-19 lockdown, when all schools were closed indefinitely. Whilst all schools reopened again, new pandemics caused by new viruses are becoming more and more possible each day, making the return of online schooling also a very real possibility. 

Genetic engineering is also very possible. CRISPR, a genome editing tool, has already been used to remove genes linked to disease from embryos. Genes linked to intelligence and lack of it have also been identified. It is not at all that speculative to suggest that genetic engineering to increase intelligence could become accepted and commonplace.

The final book on this list is Brave New World by Aldous Huxley.

This book depicts a dystopian world in 2540 AD - or AF (after Ford) 632, by the novel's own calendar. Artificial wombs are used to 'engineer' citizens, with exposure to chemicals during embryonic development, and childhood indoctrination used to sort citizens into predetermined castes. Embryos destined for lower castes are exposed to alcohol to limit growth and intelligence ,whilst embryos for higher castes are given chemicals to enhance intelligence. Sleep conditioning is used to make each citizen happy with the caste they are in. The citizens are kept peaceful and happy though the use of a happiness inducing drug and are encouraged to live freely. Exclusive relationships are taboo, with the concepts of family no longer existing. The novel explores individuality and its loss, and the effect of scientific advancement. 

The book is very speculative but the advancements it predicts are very accurate. The book was published in 1932, before many advancements in human reproduction were made, and yet it still holds up. IVF and surrogacy are accepted fertility treatments, human cloning is possible, although banned, and artificial wombs are currently in development. Multiple drugs also exist to alter mood and behaviour psychology from an early age have been proven to alter preferences.

Honestly, Brave New World is a book that everyone should read. Despite being almost a hundred years old, it is horrifyingly relevant and thought provoking. 

What I do have to admit, and this is a source of shame, is that I have never read anything by Isaac Asimov or Adrian Tchaikovsky. This may be a crime against science fiction that I will have to rectify as soon as possible. There are two books by Asimov and Tchaikovsky currently downloaded on my kindle, just waiting for me to open them. Hopefully, I will get on this before the end of the year, and this list may have to be updated or edited! Again, this list is based on my opinion and I am more than happy to be proved wrong!  But I hope that this list has given any bookworms reading this some useful recommendations on books to read next. 

Bye for now!

Jess x

Meselson and Stahl: 67 years later.

When Matthew Meselson and Franklin Stahl proposed the semi-conservative replication model of DNA, could they possibly have comprehended that their paper would still be quoted almost 70 years later?

Every biology A-level student in 2025 is taught the work of Meselson and Stahl. I remember learning it myself, and now I teach it to my students when I tutor. It is easy to forget just how important this experiment was in the advancement of genetics.

When the Watson-Crick model was released in 1953, it raised questions on how the double-helix model replicates. Meselson and Stahl aimed to conduct an experiment that could provide evidence on how DNA was able to do so.

One theory was conservative replication, suggested by Gunther Stent. Stent's theory was that the DNA helix creates two helixes; one is made up of two completely new DNA strands, whilst the second helix is made up of DNA strands that are completely the same. 

Another theory was dispersive replication. This basically suggests that the original DNA chains break apart and then recombine with new segments to create DNA that is a patchwork of old and new DNA.

Finally, the semi conservative replication theory that Meselson and Stahl found to be correct, was suggested by Watson and Crick themselves. It suggested that DNA is comprised of one parent strand and one daughter strand. 

 

Credit to IGenetics, Steven M Carr

 

To fully understand how Meselson and Stahl proved semi conservative replication, a basic understanding of radioactivity is needed- in particular, radioactive nitrogen. 

Nitrogen is known as nitrogen 14 and contains 7 neutrons and 7 protons. It is an example of an ‘isotope’ which is means that is one form that an element can take.

 Nitrogen 15 however, is a different isotope of nitrogen and contains 8 neutrons. It is rarer than nitrogen 14 and is also heavier-due to the presence of the extra neutron. 

Meselson and Stahl selected nitrogen due to it being a component of DNA. In a process called isotopic labelling, E. coli DNA was exposed to nitrogen-15. This meant that the two would be able to distinguish between parental and daughter DNA based on whether heavy or lighter nitrogen was present.

The below image shows two bands formed because of conducting this technique on equal amounts of Nitrogen 15 and Nitrogen 14 E. coli DNA:

 

Meselson and Stahl also devised a new technique to prove semi-conservative replication - Density-Gradient Centrifugation. This, along with nitrogen 15, was crucial to the experiment, as it allowed for the two nitrogen isotopes to be distinguished from each other: allowing Meselson and Stahl to prove that the daughter DNA strands contained the nitrogen 15- meaning that the DNA had to be comprised of a parental strand.

Meselson and Stahl used a concentrated solution of Cesium chloride (CsCl). In simple terms, extracted DNA was placed in this solution, and a stable concentration gradient was produced by applying the opposing processes of sedimentation and diffusion. This forced the DNA to move along the centrifugal force produced until it reached a point where its own density matched the density of the solution.

So, Meselson and Stahl exposed the first generation of E. coli only to nitrogen 15 and then transferred the E. coli to a growth medium that did not contain nitrogen 14. After growing E. coli for 15 generations, and conducting density-gradient centrifugation they were left with this image:

 

The density of the CsCl solution increases to the right, with each horizontal position representing the same density on each photograph. The right band (the only band in the topmost photo) represents Nitrogen 15. So, the only way the nitrogen 15 could be present in the later generations was if a strand of DNA from the beginning had been incorporated into the molecule. These images were taken using ultraviolet absorption. 

If the conversative model was correct, the first generation would have shown two completely different bands- one band for the molecule made up with the Nitrogen 14 and one band for the old molecule made up with the Nitrogen 15.

The first generation however fit with both the dispersive and the semi-conversative model, as it showed a hybrid. 

By generation 2 though, you can see two bands- one a hybrid weight and one corresponding to Nitrogen 14. This shows that DNA consisting of only Nitrogen 14 was being created. This meant that dispersive could not be the right model.

Arguably, the new age of molecular biology began with the DNA model in 1953, that Watson and Crick proposed with invaluable contributions from Maurice Wilkins and Rosalind Franklin. However, it is possible to argue that Meselson and Stahl really began the new age of molecular biology with their proof of semi-conservative replication.

Semi conservative replication answered a question that had been plaguing molecular biologists since the proposal of the Watson and Crick DNA model 5 years earlier; E. coli DNA replicates semi-conservatively. This suggested that eukaryotic DNA may replicate in a similar way.

 

 

Credit to OpenStax College, Biology

 

 

What came next was a series of experiments and discoveries, with only a few examples listed below:

Hot on the heels of Meselson and Stahl was Arthur Kornberg and his discovery of DNA polymerase I. In 1958, with postdoctoral fellows Maurice J Bessman and Robert I. Lehman, Kornberg purified DNA polymerase from E.coli , reported that DNA polymerase, magnesium ions and the four deoxynucleoside triphosphates were all needed to enable DNA synthesis and hypothesised that DNA polymerase was needed to act as a template 

Helicase, the enzyme needed to separate the stands of DNA, was not discovered until 1976 by Hoffman-Berling and Mackay and Linn. Meanwhile, Gyrase or Topoisomerase, the enzyme needed to stop DNA from overwinding during replication was first found in E. coli by Jim Wang in 1971.

In the 1960s, John Cairns performed a follow up to the Meselson and Stahl experiment to prove what he called ‘theta replication’- or how semi conservative replication occurs in E. coli. By growing E. coli bacteria in the presence of radioactive nucleotides and allowing DN loop A to replicate, he created DNA with one radioactive strand. The resulting electron micrograph showed that the circular chromosomes of the E. coli first unwind at a single spot, which is now termed as the replication origin. The double helix will then continue to unwind, resulting a loop- the replication bubble.

This highlights that whilst the experiment of Meselson and Stahl was the start of understanding the replication of DNA, there was still so much more to understand and discover. It also highlights how vital E. coli, an organism responsible for disease was vital in understanding DNA replication. E. coli is still used in laboratories today. 

Whilst it is easy to say that the 1953 DNA model was the most important development in molecular biology- after all, it identified the structure of DNA, it can be argued that the semi conservative experiment was the most important development. Of course, it can be also argued that Meselson and Stahl only conducted their experiment due to the theories made by Watson and Crick.

Semi conservative replication was a theory of Watson and Crick that was proven to be correct. Later, Francis Crick suggested that RNA acts as the intermediary between DNA and Protein; This was later proven by Arthur Kornberg, confirming the ‘Central Dogma of molecular biology’ first suggested by Crick. This Central Dogma still stands.

Nitrogen-15 is still used in laboratories but is now used in a technique called Nuclear Magnetic Resonance (NMR). This technique provides structural information at the atomic level but is much more challenging when being used on nucleic acids than on proteins (Nelissen et al, 2016). This highlights that Nitrogen 15 is still extremely useful in current research on RNA and DNA.

                                        

                                             Meselson and Stahl, 2020.

As every scientist knows, science only progresses due to the efforts of those that came before us. It is impossible to keep going forward, without keeping an eye backward. The ‘Modern Biotechnology Age’ would not have been at all possible without PCR, and PCR would not have been possible without first understanding how DNA replicates. So, keeping that in mind, it is only right that Meselson and Stahl remain an essential aspect of Biology A-level!

 

The best science jokes of all time... and their explanations

 I'm feeling that this week, I need to laugh a bit more. Summer is at an end, the weather is rainy and windy, it's getting dark earlier on... everything's expensive... the news is miserable so I figured that a bit of science related humour might go down quite well. 

So in no particular order, here are my favourite science jokes!

1. This is one I like to annoy my students with when I'm teaching atomic structure.

For those confused ,this is a structure of an atom- in particular, an atom of Sodium. Sodium's symbol is Na. 

Na Na Na Na Na Na Na BATMAN!

I think it's funny!

2.  Heisenberg, Schrodinger and Ohm are in a car. They get pulled over. Heisenberg is driving and the cop asks him "Do you know how fast you were going?"

"No, but I know exactly where I am" Heisenberg replies.

The cop says "You were doing 55 in a 35." Heisenberg throws up his hands and shouts "Great! Now I'm lost!"

The cop thinks this is suspicious and orders him to pop open the trunk. He checks it out and says "Do you know you have a dead cat back here?"

"We do now, asshole!" shouts Schrodinger.

The cop moves to arrest them. Ohm resists.

I absolutely love this physics joke -it's one of the few I actually understand.

Heisenberg came up with the Uncertainty Principle. It basically means that it is impossible to accurately know both the location and speed of an electron  The more accurately the speed has been measured, the less accurately the location can be measured and vice versa. So in the joke, Heisenberg has been told his speed- so know he can't know the location,

Schrodinger came up with the thought experiment about a cat. Okay, its more about how electrons can exist in two states at the same time- which becomes important in quantum physics. But what most people remember is the cat.  In this thought experiment, a cat is placed in a sealed box, with a Geiger counter and a radioactive source. If the counter detects radioactivity, it activates a poison that will kill the cat. But if no radioactivity is detected, no poison is released and the cat lives. A few days later, you come back to the box. You have no idea if the poison was released and so do not know if the cat is alive or dead. Both events are possible. Until you open that box and see for yourself, both events remain possible. This means the cat is both alive and dead.  So Schrodinger is annoyed because the policeman has basically ruined a key concept in quantum physics. 

Meanwhile, Ohm gave his name to the unit of resistance in an electrical circuit - the Ohm.  Resistance impedes the flow of electric current, reducing the number of electrons that can get though. So, as the founder of the resistance unit, Ohm , true to form, is resisting arrest.

I've always liked the idea of a group of influential scientists all having a car share together, or doing something a little anachronistic. To me, its almost as a funny as the actual joke. 

Love this cartoon. The cat is DARING the counter to detect radioactivity. 

3.Einstein, Newton and Pascal are playing hide and seek. Einstein covers his eyes and starts counting while Newton and Pascal run and hide. Pascal hides behind a curtain. Newton stops and draws a 1-metre by 1-metre square on the ground and stands in the middle. Einstein finishes counting, uncovers his eyes and turns around, "Ha! Found you, Newton!" Newton calmly replies, "Nope, you found Pascal!"

This was one of the first science jokes I learnt so I always have a soft spot for it. I also find the idea of three famous well-respected scientists playing hide and seek rather comical. Anyway, a pascal is a unit of pressure. In simple terms, a pascal measures the pressure an object is subject to when a force is applied. So, the unit of a pascal is one Newton per square metre.  So by stepping into a 1 metre by 1 metre square, Newton has made himself into a pascal. 

After a few eye rolls and giggles, I had to admit that this might make Newton a bit of a sore loser and I would not want to play any more games with him.

Bonus Joke! Isaac Newton discovered Gravity :D

4. A photon checks into a hotel. When asked if they need help with their bags, it responds, "No, I'm travelling light".

Short and sweet! A photon is literally that - a particle of light.  This is where the light wave-particle duality comes in.  Things are either comprised of waves or particles, and have different characteristics based on which one they are.  Except for light- which behaves as both.  It diffracts and interferences with other light - indicating a wave. But it also ejects electrons -suggesting its a particle. Basically, no one in physics really knows what light is.  

I also love the word play - it's travelling! Photons are how light is transmitted- for us to see anything, enough photons have to hit our eyes. They also travel at the speed of light (duh) so the photon can bring its bag up to its room faster than any porter could do!

5. Q: Before docking with the International Space Station, what must the pilot of a space module first do?

      A: Put money in a parking meteor

More of a word play joke with a science theme than an actual science joke but it's funny and relatable so it gets included.  I'm sure most of the readers of this blog have fallen prey to a parking meter at least once in their lives.  

6.  Q. What did one cell tell his sister cell when she stepped on his toe? 

      A. Ouch! That’s mitosis.

 

Oldie but a goodie! Mitosis is the process that cells use to divide and form cells that are genetically identical to each other - daughter cells. Only in biology do you have a process where divide and multiply means virtually the same thing. Anyway, for those confused, say Mi-toe-sis very slowly.

7. Two hydrogen atoms were walking down the street. The first says to the second, "I think I've lost an electron". The second atom asks, "you sure?" First one replies, "yeah, I'm positive".

Classic chemistry joke! An electron is a subatomic particle with a negative charge. Hydrogen has one electron and one proton- a subatomic particle with a positive charge. So hydrogen has lost its one electron and has been left with just a proton. It is sure that it has lost its electron because it now has a positive charge. 

8.  Q. What type of dogs do chemists own? 

     A. Laboratory Retrievers.

As a complete and utter dog lover, I had to include this one. I once used the exact logic to persuade my boss that I should be allowed to bring my Labrador Retriever to work ("But he's a LABrador- he belongs here!").  Unfortunately, the dog did have to stay at home. 

The best scientist! He's even wearing safety googles!

Scientific Accidents.

Sometimes in science, it really doesn't matter how successful your experiments are going. Or how bad they are going. Sometimes, the most amazing discoveries that have really advanced science for the better were made purely by accident.  This I think is both hopeful and damn annoying at the same time. Damn annoying because this implies that even after all your training and experience, someone in your lab who just happens to be at the right place at the right time might just stumble onto something revolutionary. Hopeful because even if everything is going wrong for you, your experiments just aren't working and nothing is going right... something great might still happen! 

So, here is my list of what I consider the greatest scientific accidents; the discoveries that no-one ever expected or hoped to make, and were only made due to errors and sheer dumb luck.  

1.Discovering Penicillin.

This is the example I always remembered when things went wrong in the lab. And I would mutter 'yeah, well, Alexander Fleming discovered Penicillin when he didn't keep his lab equipment sterile enough'. 

This is actually pretty true. 

Alexander Fleming

In 1928, Alexander Fleming was working at St Mary's Hospital, London, and was investigating variation in S. aureus, a type of bacteria. One faithful day in August Flemming inoculated several culture plates with S.aureus and left them to grow. He then went off on holiday and arrived back in his laboratory on the 3rd September. When he and his research scholar Daniel Pryce inspected the plates, they noted one had a open lid (this would make any one who has worked with culture plates gasp and shake their heads) and a blue-green mould had grown. At this point, most people culturing bacteria cultures would probably groan and sadly chuck a load of bleach in the plate. But Fleming looked closely and noted that bacteria was not growing around the mould- but it was growing normally away from the mould. This meant that the mould was killing the bacteria. Fleming then uttered the infamous words … 'That's funny'.  The words that greeted the discovery of the world's first bacteria killer were not words of eureka or amazement or success, but simple curiosity.  

Most scientists would probably just shrug and decide they have more important experiments to do, and still throw the plate away. But what was ingenious on Fleming's part was to actually collect the original mould and experiment with it. He found that the mould grew fast, it inhibited bacterial growth, and it killed gram-positive bacteria. After making a 'mould-juice', he named it Penicillin. For years, no one even know where the mould had originally come from. In 1966, it was suggested that the spores drifted into Fleming's lab from a lab on the floor above. They were able to drift in due to Fleming leaving the doors open. Also, Fleming left his plates on his bench and not in an incubator. The laboratory temperature was optimum for the growth of the mould and the bacteria- but if he had put the plates in an incubator, the mould may not have grown. 

Skipping forward some decades, Penicillin is credited for saving the lives of thousands of Allied soldiers in WW2. Penicillin started the 'antibiotic age', where hundreds of additional antibiotics were discovered and utilised. Without the discovery of Penicillin, a discovery made possible by accidents and luck, it is possible we would not have antibiotics at all. By 2025, Penicillin alone is credited with saving over 500 million lives. Antibiotics have also been estimated to extend the human lifespan by 23 years. 

The Penicillin mould. Alexander Fleming's handwriting can be seen. 

2. X-rays. 

Wilhelm Conrad Rontgen 

Who hasn't had an X-ray? These are such an invaluable part of medicine these days. In England alone from February 2022- to January 2023, 3.41 million X-rays were carried out. X-rays were the first non-invasive method for seeing inside the human body. This allowed early diagnosis of fractures, tumours, infections and also guided surgeons when operating. 

X-rays were discovered by Wilhelm Conrad Rontgen in 1895. They had been speculated about before- William Morgan in 1795 presented a paper describing a glow created when he passed electrical currents through a partially evacuated glass tube, Philip Lenard noted that rays penetrating various materials causing fluorescence on photographic plates and William Jennings and Arthur W. Goodspeed noted strange disks on photographic plates after experimenting with electricity. Nikola Tesla also noted damaged film and began investigating the energy that might have caused it. 

But it was Wilhelm Conrad Rontgen who put a name to the phenomena . He actually named the rays 'X' to indicate that it was an unknown type of radiation. The name clearly stuck! Some colleagues wanted to call them 'Rontgen rays'- to which he objected too. 

In 1895, Rontgen was conducting experiments in Wurzburg, Germany to investigate the effects of passing electricity though vacuum tubes. In one of these experiments, he added a thin aluminium window so that the streams of electrons from the electricity could escape. But as he didn't want to damage the aluminium, he added a cardboard covering. What he then noted was a flourescent effect on a barium platinocyanide-painted cardboard screen- even though the cardboard covering preventing light from escaping. He decided to repeat the experiment and darkened his lab. He then noted a faint shimmering from a bench some distance from where he was experimenting. It was coming from another barium platinocyanide screen. He noted that regular shadows were forming alongside the shimmering and called this ''rays'.  He once tried using lead instead of aluminium and stood in front of the screen and created the first radiographic image - a flicking image of his skeleton. 

Six weeks later, he then discovered the medical uses after taking a photo of his wife's hand, forming the first photograph of a human body part using X-rays. His wife didn't appear to be that happy about it, uttering the words 'I have seen my death' after seeing the photo. 

It look surprisingly little time for X-rays to be accepted. In January 1896, the first use of X-rays under clinical conditions occurred when John Hall-Edwards used them to radiograph a needle stuck in the hand of an associate. A month later, he was the first to us use X-rays in a surgical operation. 

X-rays also have impacts beyond medicine. In July 1999, the Chandra X-ray Observatory was launched. Many violent processes in the universe produce X-rays - but not visible light. The Chandra X-ray Observatory allows for observations and  explorations of stars and black holes, galactic collisions and novae exploding into space.  

All of this, from broken bones to exploding stars was made possible by a scientist noting some strange shimmers of light in his lab, his recollections of the experiments that came before and his curiosity to explore further. 

Rontgen's X-ray photo of his wife's hand. Her wedding ring can also be seen.

3.Radioactivity.

Henri Becquerel

The incredible Professor Marie Curie was involved in this as was the physicist Henri Becquerel. He was investigating a relationship between phosphorescence and x-rays, and was trying to get uranium salts to emit X-ray radiation. He believed that the uranium would do so if exposed to sunlight. So in a way, we can actually credit the accidental discovery of x-rays as being responsible for the accidental discovery of radioactivity. 

So he left a load of Uranium in a drawer (This makes me scream internally and I have to remind myself that radioactivity and its dangers were not known. But no wonder Professor Curie died of anemia caused by exposure to radioactivity and no wonder Henri Becquerel died with radioactive burns all over his skin). Underneath it, he stored a photographic plate in black paper. He kept the drawer shut. Later on, he developed the plate and discovered imprints of the uranium on the plate. This showed that they had emitted radiation strong enough to penetrate the black paper- without sunlight.  

He was able to prove that this radiation was not x-rays and that there were actually three classes of radiation. Marie Curie, Pierre Curie and Henri Becquerel began investigating this phenomenon, which led them to the discovery of polonium and radium. 

This discovery led to so so many advancements in science and medicine. It changed the way we think about the atom and showed that atoms could be divided and transformed.  It showed that the atom had a source of enormous energy, which changed thermodynamics and opened up new research into nuclear energy. Radiometric dating allowed for the age of rocks and fossils to be determined, opening up research into Earth's history. Radioactivity still plays essential roles in medicine ,with radioactive materials being used to trace bodily functions, deliver targeted treatments and study chemical processes in living cells.

Despite its danger, radioactivity is one of the most important discoveries ever made. Many scientists unknowingly sacrificed their lives for this important accident and it's only right that it's value is still appreciated, albeit with concern. 

The imprints that Uranium left behind. 

4. The Pace Maker

                                            Wilson Greatbatch. 

This artificial heart was made possible by Wilson Greatbatch.  By 2025, there are over 3 million people with pacemakers; approximately 600, 000 new pacemakers are implanted annually. 

In 1956, Wilson Greatbatch was working on an oscillator- a machine designed to record a person's heartbeat. He then made a simple but incredibly fortuitous error. Instead of grabbing a certain resistor to add to his circuit, he grabbed the wrong one. His circuit then started to produce rhythmic electrical pulses. Someone else in his position might have just rolled their eyes, muttered a few words about how stupid they were being and just connected it. But Wilson Greatbatch did something that the best of us still need to remember to do at the best of times. He listened. 

He realised that this rhythmic pulse could be used to stimulate a heart. If a regular pulse could be produced, this pulse could mimic and regulate a failing heart. The resistor that Greatbatch grabbed by mistake also resulted in a low electrical current; this meant it did not require a significant amount of power and could therefore be used to power a human heart. 

Greatbatch collaborated with surgeon William Chardack and Andrew. In 1958, they inserted the device into a dog. To their surprise, the device took control of the dog's heartbeat. In 1960 on April 15, the pacemaker was inserted into a human patient for the first time. 9 more pacemakers were inserted in the following days. In 1974, Greatbatch developed the lithium-iodide cell, which is now the standard cell to power pacemakers. 

The Pacemaker.

Whilst I've focused on the accidents that impacted medicine in this article, many other accidents resulted in products that had an impact on life and the world. Post-it notes, Sticky Putty and Dynamite were all accidents. Of course, its not enough to just make the accident. It then requires curiosity and resilience to make the accident into something worthwhile and impactful. I  think this means that sometimes, the best thing you can do in science is realise that something went wrong, but work out why. Sometimes, the best thing you can do is find the value in the wrong and the weird!