Neutron

There is a recipe in the back of Edward Lear's Book of Nonsense which begins like this:

"Procure some strips of beef,  and having cut them into the smallest possible slices, proceed to cut them still smaller, eight or perhaps nine times."

The recipe raises some interesting questions such as: What would these tiny pieces of beef look like? Is it even possible to slice anything past the molecular level? There is another question I am more interested in. If you slice things into small pieces, they take up less space. Could you eventually make things disappear entirely, just by slicing them?

As a matter of fact, it is fairly easy to break apart molecules; your body is doing it now. Atoms are more tricky, but scientists have split the atom more than seventy years ago. You rely on atoms fusing together in the Sun, after all. To answer our first question, the beef wouldn't look like beef past the molecular level. In fact, if you managed to split apart every single molecule in a slice of beef at once, it would trigger an explosion as the oxygen fuses to form the kind of air you breathe. (if you did the same thing to atoms, you would make a large nuclear explosion.)

Of course, it takes some pretty tremendous forces to split atoms. The only place where it is done on a big scale is in the core of a large star, when it dies. If a star is much bigger than our sun, it struggles constantly to stop collapsing in on itself.  The star relies on fusing atoms to survive. The moment a star runs out of fuel, its inner layers collapse. The outer layers of the star crash into the inner layers, and rebound into space in what is known as a supernova. What is left is the core. In a Sun-sized star, the core left is a white dwarf, which glows for a while before winking out. However, in a large supernova, the atoms are so strained by gravity they split apart and form an extremely dense and often quickly spinning object known as a neutron star.

Neutron stars are really strange things. They can be the size of cities but the mass of the Sun. They are mostly made of neutrons. Many have a fragile 'crust', which can fracture and create terrifying power surges. Some orbit a star, which they suck power from. Sometimes neutron stars merge and create massive bursts of light. Some neutron stars, known as pulsars, spin several times a second and emit energy from their magnetic poles.

Most weird aspects of neutron stars come from their incredibly small size and their amazingly large amount of mass. There is a type of object which has even more mass and a smaller size than a neutron star: a black hole. Black holes are made by splitting the components of atoms apart into individual quarks. Black holes are really weird. They are objects with a gravitational field so extreme, they can bend light. You cannot even see a black hole; you just see, well, a black hole. Around a black hole, time slows down and everything is redshifted. We barely know anything about black holes at all. All we know for sure is that they are unimaginably small and dense.

I wish there was a way to split quarks - the components of neutrons and protons - apart, but there isn't, as far as we know. And finally we arrive to the answer of our third question: It is not possible to cut a slice of beef into nothing, but you can make a black hole.

Cultures

I noticed a lot of things in Switzerland that were not in Australia, America, or even northern Europe. One of them was the mountains. Australia's highest mountain is a mere hill compared to even the lowest mountain in Switzerland. Even the Rockies are no comparison to the mighty Swiss Alps.

However, the mountains were not what struck me most about the country. What struck me most was its culture.

The culture of an area is its identity. If someplace has a very old, established culture, it becomes instantly recognizable if you happen to be there. Australia was never properly populated before the Industrial Revolution, so its culture was mostly stolen from other continents; in Europe, however, country and even regional borders are obvious.

Let's take Italy and Switzerland - the two countries I visited this July. These two places, although neighbors, are shockingly different. One has been neutral for the past hundred and fifty years; the other has been heavily involved in both world wars. One has had a long history of organized crime; the other is one of the safest countries in the world. One makes great cheese; the other makes even better pizza. When I visited Italy on a day trip, the border between the two countries was obvious. It was marked on a pass by two massive stone eagles (a memorial of some battle victory in the Napoleonic Wars). To the north, there was a valley and beyond that, icy snowcapped mountains. In the valley there was a town with a visible church. The town seemed to have no center; it was stretched out across the valley floor. To the south, in Italy, the mountains tapered off abruptly and gave way to rolling hills, all sparsely covered with houses and lakes.

Cultures are interesting in the way that they carry on even when the geography that shapes them does not. For example, in Switzerland, there are two geographic regions: the Swiss Alps and the Rhineland. In the Swiss Alps, where Switzerland was first created, there is almost no flat land at all, except for that thin ribbon of farmland at the floor of each valley. As a result, all towns have only one road of any importance and the shops are spread out over hundreds of metres, sometimes kilometres. Curiously enough, when Switzerland grew to encompass the Rhineland, the system carried on. Look at a map of any city established under Swiss rule and you will see a distinct linear pattern.

My favorite thing about Swiss culture is the architecture. Architecture varies greatly all over the world. Even if a region has none of its own food, town layout or traditions, it will have its own architecture. Swiss houses and hotels have strange roofs for a place with a lot of snow; they have almost vertical outer sides and very flat tops, like boxes. Not all of them do of course; it's different in every single valley, just like the food and many other things are. And that's what I like most about Swiss culture: its variation.

Invisible light

We perceive the world in the three colors that our eyes can sense- red, green and blue. This gives us a visible range of all of the wavelengths in between 390 and 750 nanometers. However, there are wavelengths in the infrared and the ultraviolet that, if viewed by a special camera, can reveal much more about the world than our eyes can. I am working on a project to build a new type of these cameras. In the following paragraphs, I will explain more about how they work and about the one I built.

Cameras that can see past red and past violet are called multispectral cameras. These cameras can be mounted on satellites to view natural features and cities in a way that no ordinary camera can. There are many different regions of the spectrum, most of which can only be seen with the aid of such a camera. The ultraviolet is mainly used to photograph biological compounds, while the near-infrared has a wide range of applications. The near-infrared is a band of wavelengths that is just beyond red. It ranges from 750 to up to 1400 nanometers. Even though this is beyond visible, these wavelengths are still extremely small- up to 1.4 times a thousandth of a millimeter.

The way to reveal the most about an object using multispectral imaging in the near-infrared part of the spectrum is to filter out one wavelength at a time. However, technology that can do this is very expensive. This is why I am working to make a cheaper multispectral camera.

Instead of filtering incoming light into different wavelengths, this camera works by having both the camera and the object inside a box to block out all other light, and illuminating the object with LEDs that emit light in various wavelengths in the visible and near-infrared parts of the spectrum. Both the LEDs and the camera controlled by a type of small computer called a Raspberry Pi. The computer is programmed to flash each color of LED in succession while taking pictures with the camera. This way, the images can show how an object reflects and absorbs different wavelengths of light individually. This method is cheaper, and its only limitations are the spectral range of the camera and the variance of the LED colors.

For the programming of the camera, I used a programming language called Python, with which I was able to write the programs for the operation of the camera over an internet connection with the Raspberry Pi. One of the problems I faced was how to make a Printed Circuit Board(PCB) that included places for all of the LEDs so that I could solder them. I did this with a program called gschem.

The type of multispectral camera described above can potentially have many uses in agriculture. It would be able to detect bruises on fruit and possibly detect when it goes rotten much faster than human eyes can. It could also detect diseases in plants. In conclusion, multispectral cameras can be very useful to help us understand the world we live in more fully.

References:
https://en.wikipedia.org/wiki/Multispectral_image
https://en.wikipedia.org/wiki/Near-infrared_spectroscopy

Grain of Sand

It is no wonder that geologists swarm to the Jack Hills, Western Australia -- for it is the site of the oldest rocks on Earth.

There are larger old rocks in Canada, but they are 500,000,000 years younger than the Jack Hills rocks. There are older meteorites in Antarctica, but they were not formed on Earth. The rocks at the base of the Grand Canyon -- thought by many to be the oldest rocks on Earth -- are a whopping 2,650 million years younger than the rocks of Jack Hills.

Being about 4.4 billion years old, some rare Jack Hills sand grains came from the first rocks Earth ever had. However, the old rocks of the Hills are just that: a few very rare sand grains, called zircons, which are deeply embedded in sedimentary (made of sand) and very metamorphic ('changed') rocks. How did these tiny grains appear here in the first place, and how might they have survived the wear of time? Why are they so rare in the first place? Let's go back in time to find the answer.

The Crust Solidifies

4.4 billion-years-old Earth is not a place you would want to live. A human, dropped on the prehistoric planet's surface, would be fried by nuclear radiation, burned by lava, choked to death by poisonous gases, and crushed by meteorites within the first five minutes. One good thing about early Earth: Oceans. Scientists have found out that the Jack Hills zircons were created in water; water which could have come either from meteorites or the planet itself. In any case, Earth had oceans, but still wasn't cooled enough for the igneous rocks to turn into anything else, whether sediment or metamorphic rock. Also, there was virtually no oxygen. This meant, for now, that the early rocks were safe from change. That is, until . . .

Life Begins

Life is currently thought to have originated around 4.0 or 3.9 billion years ago. The oldest evidence for life comes, like the earliest evidence for water, from those same Jack Hills sand grains. Life did not have much effect on early rocks until about 3.4 billion years ago, when the Earth had cooled down significantly and erosion had begun creating the first sedimentary rocks. Around this time, moss-like cyanobacteria began making the first stromatolites (crazily, the only colony of stromatolites left is within sight of the oldest rocks). Cyanobacteria use photosynthesis, a complicated process which turns carbon dioxide, water, and sunlight into sugar and oxygen. The latter was released on a massive scale into the atmosphere. This would not have been that bad, but there was a lot of iron in the volcanic rocks. The oxygen and iron combined to form rust, and immediately the age-old rocks from Earth's creation began to fall apart. Jack Hills zircons, not being made of iron, had survived for the time being. However, an important factor was now coming into play . . . .

Radiation

There were trillions of trillions of zircons on Earth when it was first created. Corrosion and heat did not change their numbers very much. However, around three billion years ago, the zircon crystals began to break apart, due to a process known as metamictization.

Early Earth was very, very radioactive. Rare elements today, like actinium, used to be very common four billion years ago. Uranium-238, the most common radioactive element, has a half-life of about 4.5 billion years. This means that a 200-atom sample of uranium from the creation of Earth would have about 100 atoms now (the other atoms would have turned into something like radium). A by-product of radioactivity is radiation, in this case in the form of alpha particles. You may expect a zircon to have had about a million atoms of uranium in it 4.4 billion years ago. By now, the decaying uranium would have released at least 500,000 alpha particles -- more because what uranium decays into, decays into something else. 500,000 alpha particles are more than enough to destroy the crystal.

A few, very rare zircons would have survived long enough to endure the next test.

Plate Tectonics

In 2013, scientists were shocked to recognize the remains of a massive continental plate, lodged deep within the Earth underneath North America. This plate was called the 'Farallon Plate', and was later discovered to have been shoved underneath the crust by the Pacific and North American plates.

As shocking as it may be, it is not uncommon for a continental plate to slide underneath the crust, never to come back again. It has happened throughout the history of the Earth since plate tectonics began, around 4 billion years ago. Every 300 million years or so, the Earth's crust is recycled. Our zircons could hold out under the immense pressures of the Mantle for a while. Eventually, however, even the strongest crystal on Earth could not survive.

What saved our zircons is exactly what destroyed all the old rocks: Erosion.

The zircons, swept by the wind, would have spread across the world, minimizing the chance of all being destroyed. They would become part of normal sandstone rocks, which would erode and the zircons would have been released again. Nevertheless, the oldest zircons became rarer and rarer. Finally, around 600 million years ago, a group of zircons became embedded in some sandstone rocks. Eventually, as most of their neighbors were slowly destroyed, the last zircons got buried under heaps of volcanic rock. The surrounding land went through cycles of burial and erosion, but the zircons were protected by the volcanic rock. After being warped by pressure, the sandstone containing the zircons slowly, but surely, was uncovered. It was now part of the western Australian plate.

The Adventures of Gold

The Adventures of Gold

Gold was inside his shop, making magic wands like he always did on sunday afternoons.

However, it was not a Sunday afternoon. It was Friday morning. Normally, he would be in some important government meeting, but not today. Today he got the day off. But why did Gold make wands to sell at his shop during free time? Surely not money! He was the richest and most famous dragon in Great Britain! He did it purely for fun. Suddenly the doorbell rang.

“Come in!” yelled Gold. The door creaked open. Suddenly, a young cat burst through the

doorway so fast, he broke one of Gold’s Ming vases into a million pieces.

“Gold! You’ve got to hear this!” he said.

“But my Ming vase!” Said Gold.

“Come on!” Said the cat. “Your Ming vases come from Squeaky-E-Mart and cost ten cents! This is more important!”

“But…” said Gold.

“Listen to me!” said the cat. “The candy factory shut down!”

Gold froze in place. Even though he was middle aged, his longing for candy was stronger

than ever.

“Why did the owners shut it down?” said Gold.

“They didn’t.” said the cat. “The Vipers did”

“Who are the vipers?” said Gold.

“The vipers?” said the cat. “The Vipers are a famous gang of bulldogs. They have done worse and worse things over the past few years. yesterday they blew up a bridge.”

“But how do you know that the Vipers shut down the factory?” said Gold.

“I got a ransom note.” said the cat.

“May the King help us!” said Gold.

“I am the King.” said the cat.

“Oh. Right. Sorry.” said Gold. “Your hair style mislead me.”

“So how do we get them?” said the King.

“A crystal ball!” said Gold. He pulled an apple sized ball out of a cupboard.

“How does it work?” said the King.

“You say something into it and it takes you there!” said Gold.

“What makes it cloud up like that?” said the King.

“Cloudy apple juice.” said Gold. “The crystal ball only has one charge, so we have to use it wisely.”

“Go ahead.” said the King.

“Take us to the Vipers!” said Gold. Suddenly, in a whirlwind of colors, they got transported 

to a dingy old room with four bulldogs huddled around a table.

“Hands up!” said Gold. A bulldog spun around.

“What do you want?” said the Bulldog.

“Fix the candy factory!” said gold.

“We never shut it down.” said the Bulldog. “The ransom note was a lie!”

The next day, Gold was helping the King put the Vipers in jail, as well as whining his head off.

“I wasted a crystal ball, a train ticket a boat ticket, lots of time, and most importantly my 

ming vase, only to find that nothing happend at all!” said Gold.

“Not really.” said the King.

“What do you mean, ‘not really’?” said Gold. The King pulled a trophy out of his bag.

“As your King, I give you this award for helping me capture the most troublesome gang in Great Britain.” said the King.

                                                        The End!

Hydrogen

 Hydrogen is the simplest and most abundant element on the periodic table. It consists of one proton and one electron. Its atomic number is 1 and its chemical symbol is H. Through this post I will write about its importance in the past, its fourth state of matter, and the inner beauty that it exhibits light-years away.

The Hindenburg disaster

Hydrogen was named after the two Greek words υδρο(hydro), meaning water, and γενης(genes), meaning creator, when it was discovered to create water when burned. In its pure state, hydrogen is a gas that is invisible and highly flammable. Because of its low density, hydrogen  is one of the two atomic elements that is lighter than air. this makes it able to float large objects. People took advantage of this fact by building blimps(zeppelins), aircraft that use the lifting power of hydrogen. They carried more than 35,000  passengers over the years from 1910 to 1914 without serious accident, but on 6 May 1937, the passenger airship Hindenburg mysteriously caught fire and crashed in New Jersey. From then on, hydrogen was considered far too flammable as a lifting gas.

As a gas, hydrogen is colourless, odourless and tasteless, yet we benefit from it every day. It is visible as a plasma in all stars, including our sun. The sun is mostly hydrogen that has been exposed to high temperatures or a strong electromagnetic field, converting it into plasma, the fourth state of matter. As a plasma, the hydrogen atoms are stripped of their electrons. This makes it possible to fuse hydrogen atoms together into helium, and to produce the intense amount of heat and light that is crucial for the Earth's ecosystem.

Hydrogen, like all other elements, has a dark side. The sun constantly emits positively and negatively charged hydrogen ions through interplanetary space. This is called solar wind. These particles can travel at up to one million miles per hour. Fortunately for us, Earth is protected by a magnetic field, which shields the planet from solar radiation. Were it not for this magnetic field, much of the Earth's atmosphere would have been stripped away by solar wind, rendering it lifeless.

The Ring nebula

Hydrogen was first created by the big bang, roughly 13.7 billion years ago. Ninety percent of the universe consists of Hydrogen, which is mostly in stars and nebulae. Nebulae are mostly ionised hydrogen which glows in hydrogen's spectral emission lines. When I lived in a place with less light pollution, me and my family went outside with a telescope to look at the stars. One object that is visible in the Australian night sky is the Orion nebula, which appears as the middle 'star' in Orion's sword. My favourite nebula is the Ring nebula, which lies in the constellation Lyra.

Base systems

A base system is a system in which we count. Most people are familiar with the normal base-10 system, also called the decimal system. Each base system has its own unique set of numbers, like the decimal system, which has exactly ten.

The good thing about using a base system is that there does not have to be a different symbol for each number, which would be very confusing and hard to keep track of. Instead, the numbers count up through all of the symbols in the whole system, and then the system adds an extra digit and starts over again.

Computers have to bring this to the minimum, because an electrical current is either off or on. It is hard to get more information with simple digital devices, such as transistors, and it is hard to vary the current in any other easily detectable way. This results in only two "symbols" that a computer can use, so in counting, computers use the base-2 system, or the binary system.

Binary
The two 'symbols' in the binary system are usually represented by 0 and 1, and they are referred to as bits. These can combine to make long sequences that are used in computers. For example, whenever you press a letter on a standard keyboard, an eight-bit sequence of ones and zeroes gets sent to your computer.

Even though binary is simple, it also gets very long. All of the numbers from 0 to 10 in the decimal system can be represented as 0, 1, 10, 11, 100, 101, 110, 111, 1000, 1001 and 1010 in binary. All of the even numbers end with a zero, and there is a twos place, a fours place, an eighths place, a sixteenths place and so on. A computer byte, or eight digits of binary, can range through all of the numbers from 0 to 255. 109 in the decimal system is the same as 1101101 in binary.

Octal
The next counting system I want to focus on in this post is octal. This is the base-8 numeral system. Octal has been used by some of the native Americans for counting, because they counted on the spaces in between their fingers, and not the fingers themselves. Over history, octal has been proposed for many things such as coinage and counting, but in the present day, it is not widely used.

Octal uses only the digits 0-7. One helpful thing about the system, is that eight is the cube of two, or 2x2x2. This makes multiplication and division easier. The number 109 is represented by 155 in octal.

Decimal
The next system is also the most commonly used; the base-10 system, or the decimal system. We use the system only because we have ten fingers, so we have the decimal system solely due to evolution. If we had evolved with four fingers on each hand, we would be using octal!

The decimal system is very old. It was used by the ancient civilisations of Greece, Rome, Egypt and China. The oldest decimal multiplication table was made out of bamboo slips and came from the Warring States period in China. Romans had an interesting way to make decimal numbers, only needing numerals for 1(I), 5(V), 10(X), 50(L), 100(C), 500(D) and 1000(M). The Ancient Greeks did not use numerals, and instead used the letters Alpha-Theta as the numbers 1-9, Iota-Koppa as 10-90, and Rho-Sampi as 100-900. The number 148, for example, is translated as ρμη(RUE) in Greek(Notice that the Greek counting system includes the three letters Digamma, Koppa and Sampi, which are now obsolete in language). 109 in decimal is the same as the number 109. This example is not needed.

Duodecimal
One numeral system that is commonly used in America is the base-12 system, also called the duodecimal system or sometimes dozenal. This system is used today in foot-inch and single-dozen-gross-great gross systems as well as most clocks. You might sometimes refer to the number six as 'half a dozen', or twenty-four as 'two dozen'. In the duodecimal system, 24 translates to 20. The duodecimal system can be helpful because it is divisible by 2, 3, 4 and 6.

You may notice that in all of the systems I listed before, only numbers from the 0-9 set are used, however duodecimal has to count through all of the numbers 0-11 without adding another numeral place. This means that the system needs extra symbols to represent 10 and 11. These can be an inverted 2 for 10 and an inverted 3 for 11. The number that is 139 in the decimal system is the same as 37 in the duodecimal system.

Hexadecimal
The next numeral system is based on 2 raised to the fourth power: the hexadecimal system, or the base-16 system. This system requires sixteen different symbols, so the letters A-F are used for the numbers 10-15.

The hexadecimal system is highly involved in computer screens. Each pixel on the screen of a computer is made of three different lights, coloured red, green and blue. The brightness of each of these lights can be adjusted from 0(off) to 255(maximum brightness). This can vary the colours of each pixel. For example, red=255, green=128, blue=0 can colour a pixel bright orange. Each number in between 0 and 255 can be expressed as an eight-digit number in binary, or a two-digit number in hexadecimal. Six-digit series composed of hexadecimal numbers are used in HTML and other programs, two digits to represent each colour. In this form, bright orange would be #FF8000. 139 translated into hexadecimal would be 8B.

Vigesimal
The vigesimal system is the base-20 numeral system. It consists of the numbers 0-9 and the letters A-J. The letter J represents 19. It is used in the Mayan and Aztec language with its own symbols. This system is not all too different from the decimal system, because it is based on two times ten. 139 is 6J in vigesimal.

Sexagesimal
Sexagesimal is the last numeral system in this post. The extremely helpful thing about sexagesimal is that its base, the number 60, can be divided by 12 different factors including 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, and 60. It was used by the Babylonians, but I would not say that their counting system was completely base-60, because the Babylonians used decimal as a sub-base.

Of course, sexagesimal is still used today, in geographic coordinates(degrees, minutes and seconds), and time(hours, minutes and seconds). On clocks, the system fits together well with the duodecimal system, because exactly five minutes fits in between each hour. It is no wonder that this system, which was used by the Babylonians, is still used today!


Resources: Wikipedia, "List of numeral systems"