Why are there lasers in the desert???

By Austin Monestel

We’ve probably all heard of Newton and his discovery of gravity. Throw an apple up in the air and it will decelerate and then fall back to Earth. However, treating gravity as a force is only good to a limited extent, because that’s not entirely accurate to what gravity is. So then what is gravity? What is LIGO and how does it work? Well that’s exactly what this article is about. 

Gravity and Space-time:

In the early 20th century a physicist named Albert Einstein, who you may or may not have heard of, came up with a theory that changed the way physicists looked at gravity. Before, astronomers were having difficulties explaining certain observations like Mercury’s orbit around the Sun. When normal Newtonian-physics and mathematics was applied to Mercury, it’s orbit made no-sense with what had already been observed and measured by telescopes. What could explain this? Scientists first thought that maybe there was another planet that was in orbit around the Sun that was pulling on Mercury. After all, the same thing had happened with Uranus when we realized that another planet, Neptune, was pulling on its orbit. The problem was, they couldn’t find the planet and began assuming that there was a planet there but the Sun was just too bright to see it. They named this mystery planet Vulcan and it was thought to be there up until the early 20th century. Albert Einstein had published a theory that would later be called “The General Theory of Relativity.” Einstein imagined that if all the mass in the Universe was taken away, space would be a two-dimensional sheet. If you were to then put mass back onto that sheet, called a manifold, it would bend the manifold of space itself. This bending is the reason the Earth orbits the Sun and the Moon orbits the Earth. When astronomers took the General Theory of Relativity’s math and applied it to Mercury’s orbit, the planet Vulcan disappeared in a second and Mercury’s orbit now made sense.

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The manifold of space-time and how the Sun and Earth affect it.

Part of Einstein’s General Theory of Relativity, the man imagined what would happen if large masses collided with each other and realized that it would form waves in the manifold of space-time much like a stone creates ripples when thrown into water. These would later be called gravitational waves. These gravitational waves actually stretch and move the Earth when hit however it only affects Earth by smaller than the size of an atom so it’s not very noticeable. That is, until LIGO was built.

LIGO: Giant Concrete Tunnels in the Desert?

In the mid-1980’s, funding and building began of a joint project by MIT (Massachusetts Institute of Technology) and Caltech (California Institute of Technology.) This project, named the Laser Interferometer Gravitational-wave Observatory (or LIGO for short), would be created for the sole purpose of detecting Gravitational-waves. The observatory works by creating a laser beam that comes into contact with a lens that splits it in two and shoots them at 90° from each other. Those two beams then travel through two, evacuated, 4 km steel tubes and reflect off mirrors at the end of it. Finally those laser beams travel back to their starting point and converge again. This convergence causes a light pattern to be created on an adjacent wall. When gravitational waves hit the Earth it causes interference in the laser beams and this changes the light pattern. The problem is that any vibration could cause an interference pattern. So, they had to build it in a rural area away from cars and in an area with a low-amount of earthquakes. To make sure that no vibration could lead them to a false conclusion, they built two separate observatories in Hanford, Washington and Livingston, Louisiana. Has all this hard work paid off? Yeah. On September 14, 2015 both observatories detected an interference pattern and were able to correlate it with a collision of two, large, black holes. The fellows at Caltech and MIT even created an audible sound that would be what that collision would sound like if there were air. You can search it up on the internet and listen to it. 

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One of the ends of the LIGO facility.

So, ultimately, the importance of LIGO has already been revealed. It will continue “listening” for gravitational waves and the folks at Caltech and MIT hope to detect the collisions of objects like neutron stars and other black hole collisions. It’s just astounding the feats of science humanity has achieved. Just a few hundred years ago, astronomers were barely being able to see Saturn’s rings and now we can detect massive black hole collisions that take place lightyears away.

Sources

https://www.ligo.caltech.edu/page/timeline 

https://www.youtube.com/watch?v=DjcS1kRkc6M&t=119s

https://www.youtube.com/watch?v=w8PoG3mvqk8&t=922s

https://www.forbes.com/sites/startswithabang/2018/06/09/ask-ethan-if-mass-curves-spacetime-how-does-it-un-curve-again/?sh=1304df9746a0

https://commons.wikimedia.org/wiki/File:Northern_leg_of_LIGO_interferometer_on_Hanford_Reservation.JPG

The Growing Challenge of Climate Change

By Catarina Dantas

Above all, we must set the example: by fostering energy transitions, investing in sustainable cities, and promoting global awareness. The key to a sustainable future lies in our hands.

Climate change is no longer a scientific hypothesis, a problem for a distant future. It has recently proven to be a generation-defining challenge, a clear and present threat to our collective survival. 

Last summer, record temperatures caused wildfires to burn vast natural reserves on the Western Coast of the United States. The amount of carbon dioxide thrown in the atmosphere was superior to the UK’s entire power sector’s annual emissions. 

Around the same time, a severe drought made the Pantanal wetlands in Brazil an easy target for a deadly combination of human-made and natural wildfires. The loss of biodiversity in one of the world’s top wildlife sanctuaries was genuinely heartbreaking. The images of desperate jaguars cornered by the burning vegetation were a metaphor of our condition in the face of anthropogenic climate change.

Super-storms in the South Atlantic, giant hurricanes in the Gulf, melting ice-caps in the Arctic: the evidence of the damage we are causing to our planet is overwhelming. And yet, many individuals, corporations, and governments either deny the problem or refuse to act with the necessary vigor. 

We cannot stand idle. We must move now: by electing committed leaders, fighting obscurantism, and supporting international environmental cooperation under the Paris Agreement. Above all, we must set the example: by fostering energy transitions, investing in sustainable cities, and promoting global awareness. The key to a sustainable future lies in our hands.

The Pros and Cons of Nuclear Energy

What is the future of clean energy?

By Joao T. Corbett

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What is Nuclear Energy?

Before entering the discussion on the merits of nuclear energy, it is imperative to have a basic understanding of the science, and history behind it. After the nuclear bombings of Hiroshima and Nagasaki in 1945, people believed that the power used in the bomb could be diverted into the production of clean, and cheap energy. The only problem was that the research for power plants had not been yet developed, and the money needed for their production was in short stock. This problem continued into the latter half of the 20th century until the Yom Kippur War in the middle east drove up the price of oil. This ushered in a decade of large investments in nuclear energy. The reactor chosen for this task was the relatively basic light water reactor. 

This reactor works by using an artificial nuclear fission reaction to heat up water which then spins a turbine, thus creating energy. The main fuel for this reactor is the very unstable Uranium 235. Within the reactor core, neutrons are catapulted at Uranium 235 atoms until they split into smaller, more stable elements releasing large amounts of energy in the process. 

Although this age saw a considerable increase in Nuclear energy and a heightened amount of investment, it was cut short by two major accidents that occurred within these plants. The first of these was the three-mile Island accident in Pennsylvania, the USA, and the Chernobyl disaster in Soviet-occupied Ukraine. The catastrophes resulted in a mass public disillusionment with nuclear energy resulting in a drastic decrease in funding, and less funding for the research. Today, only ten percent of the world’s energy is produced by about 439 nuclear plants in thirty-one countries. This number is mostly comprised of the aforementioned light water reactor

Cons

Critics of Nuclear energy either believe that nuclear energy is far too dangerous for human exploitation and that its cons vastly outweigh its benefits. The argument against nuclear energy can be relegated to three main reasons. The first of these is the potential for the development of nuclear weapons, in the name of clean energy. The fact is that it is extremely difficult to develop nuclear power plants, without developing nuclear bombs. It is also nearly impossible to distinguish nuclear energy projects from nuclear bomb projects. This worry has already been proven true when countries like Pakistan, India, South Africa, Israel, and North Korea were able to develop weapons in the name of energy. These weapons, if fallen into the wrong hands, could potentially cause the end of human life on earth. The second of these arguments is in regard to the deadly waste produced by nuclear power plants. This waste is not only radioactive but also contains extremely dangerous elements such as plutonium. A milligram can kill a fully grown man, and a few kilograms can make an atom bomb. It is no surprise that this waste is very difficult to dispose of, and of the 31 countries producing waste, only Finland has a permanent, effective institution that takes care of the waste. The final argument is that nuclear reactors are far too dangerous, and have already taken thousands of lives, and rendered large areas uninhabitable for decades. 

Pros

Supporters of nuclear energy believe that the benefits of nuclear energy far outweigh its drawbacks. The argument in nuclear energy can also be condensed into three main reasons. The first of these reasons is based upon a 2013 study conducted by NASA which concluded that nuclear energy saved about 1.8 million lives between 1976, and 2009. All this might seem rather strange, due to nuclear energy’s many accidents, it is important to account for the type of waste produced by nuclear power. Nuclear waste, though extremely dangerous, is a controllable by-product, which can be stored. This is not the same case for the bi-products of other energy sources which are simply pumped into the atmosphere. This reduction in atmospheric pollution has resulted in a considerable decrease in lung cancer, and other conditions derived from said pollution. The second reason further expands upon the previous and is that in relation to CO2 emissions, nuclear energy is the cleanest source of energy. It produces very little emission which not only saves lives but also reduces the effects of climate change and its consequences. Nuclear energy is also the only reliable clean source of energy that can constantly produce energy without being reliant upon controllable factors. The third reason is simply that nuclear energy is an ever-expanding field of research, and most of the reactors of today use outdated technologies employed in the 1970s. An example of this includes the thorium reactor which uses thorium instead of Uranium 235 for its fuel. It is very difficult to make nuclear weapons from thorium, and it produces 200 times the energy and less than half of its waste. Another advancement is the recyclability of nuclear waste, which could potentially eliminate the waste problem altogether.

Sources

Char, N L, and B J Csik. “Nuclear Power Development: History and Outlook.” IAEA, IAEA,1987,www.iaea.org/sites/default/files/publications/magazines/bulletin/bull29-3/29304781925.pdf. 

Kharecha, Pushker, and James Hansen. “Coal and Gas Are Far More Harmful than Nuclear Power – Climate Change: Vital Signs of the Planet.” NASA, NASA, 5 Nov. 2015, climate.nasa.gov/news/903/coal-and-gas-are-far-more-harmful-than-nuclear-power/. 

Zarubin, Bobby. Introduction To Light Water Reactors, 7 Mar. 2016, large.stanford.edu/courses/2015/ph241/zarubin1/. 

*Special mention to Kurzgesagt nuclear energy series, below are links to each of the videos in series.  

https://www.youtube.com/watch?v=pVbLlnmxIbY

https://www.youtube.com/watch?v=HEYbgyL5n1g

https://www.youtube.com/watch?v=rcOFV4y5z8c

Are We in The Midst of The Next Mass-Extinction Event?

By Austin Monestel

If we go extinct, what animals will follow after us? Who knows, maybe a species smarter than us? A species that has all of our virtues and little of our flaws.

Imagine a world filled with only grassy plains and towering trees. Imagine living in this world, being oblivious to the world around you. Now imagine a bright flash of light, the Earth rumbles beneath your feet as the ground splashes like water. This was what happened to the dinosaurs and all the other animals on the planet about 65 million years ago. After a meteor hit the Earth, it created a chain reaction that killed 75% of all life on Earth at the time. We know about this because a crater 150 km in diameter still remains buried underneath the country of Mexico. This was only one of the five mass extinction events in the history of life on Earth. The names of all these events are: The Ordovician mass extinction, The Devonian mass extinction, The Permian mass extinction, The Triassic-Jurassic mass extinction, and the Cretaceous mass extinction. Ironically, the Cretaceous mass extinction (the one that killed the dinosaurs) is the most famous event yet it’s not even the deadliest mass extinction event. The deadliest extinction event was one that killed 96% of all life on Earth. One that had so much death that it even has the nickname “The Great Dying.” This was the dreaded Permian extinction. Okay that’s pretty terrifying, but what if I told you that a sixth corridor is being built in the Halls of Extinction? What if I told you that the next “Dying” is closer than you think? 

Okay, enough fear! Now let’s get to the science! First, we need to define a mass extinction. The scientific consensus is that a mass extinction is an event or multiple events that cause a great number of animals to go extinct. Some articles even say that a mass extinction is an event or multiple that cause 75% or more of the current species to go extinct. However the majority don’t really have a specific number and instead focus on a definition that a great number of the animals went extinct over a short period of time. It’s important to understand that a mass extinction isn’t caused by only meteors like the Cretaceous extinction. In fact, any event that causes a great number of animals to go extinct can be considered a mass extinction. For example, the Permian was thought to be caused by a large number of volcanic eruptions which released a lot of hydrocarbons into the atmosphere and caused the climate to heat up. In addition, the volcanic eruptions also caused toxic chemicals to be released into the air and water which severely poisoned the Earth. Now that we understand what a mass extinction is we can look at how the world around us is following a pattern that leads to a potential mass extinction event.

So right about now you’re probably wondering how we could be in a mass extinction event? Well, it’s mostly our fault. Turns out, it hasn’t taken humans too long to mess up the Earth’s ecosystem. Believe it or not, homo sapiens (Humans) have only been on the Earth for around 200,000 years. To put that into perspective, dinosaurs roamed the Earth for 175 million years before they went extinct. Within 200,000 years we managed to make all sorts of animals go extinct such as the wooly mammoth, the wooly rhino, carrier pigeons, dodo birds, and many more. We even caused our distant ancestors, the Neanderthals, to go extinct. You’re probably thinking that we may have caused some animals to go extinct but that’s no reason to call it a mass extinction. The reality is that so many more animals will go extinct in the upcoming decades. We’ve already found that roughly ½ of land animals have lost 80% of their habitat. A good example of this is the lion habitat. The lions used to be found in the majority of Africa, the Middle East, and even up to Southern Europe. Now, lions are only found in select places of Central and Southern Africa. The IUCN (International Union for Conservation of Nature) found that 38% of the species assessed are currently threatened with extinction. The majority of these animals are threatened due to human encroachment such as deforestation, overhunting, and toxic pollution. Some scientists say there may be a possibility of ever so slightly turning it around but that, unless we humans get our overpopulation under control, a “biological annihilation” is very likely. “The time to act is very short. It will, sadly, take a long time to humanely begin the population shrinkage required if civilisation is to long survive, but much could be done on the consumption front and with ‘band aids’ – wildlife reserves, diversity protection laws – in the meantime,” Prof. Gerardo Ceballos said in an interview with Guardian News. On the other hand, some scientists say that we’re in the beginning of a mass extinction event and can still easily turn it around. The worst part is, humans may even be on the chopping block. If this “biological annihilation” occurs and a massive amount of wildlife go extinct, then starvation rates may spike as people die of hunger. When this happens the population will be decimated and may even go extinct. In addition, as trees are cut down for human use the amount of carbon dioxide will increase causing the air to become toxic and a climate change similar to the Permian extinction will occur. This climate change will cause fresh water to evaporate as droughts become much more frequent.

That’s pretty scary, but there is a good side to everything, and mass extinction events are no exception to this rule. Mass extinction events may cause a large number of animals to go extinct, but you can also think of it as wiping the slate clean. Often, after a mass extinction event, new animals are given the opportunity to evolve. Before the Cretaceous meteor event, the first mammals were very primitive. They were rat-like ancestors that burrowed deep underground to avoid predators. However when the meteor hit, the first mammals were able to endure due to their ability to burrow and control internal body temperature. After the rubble settled, the first mammals crawled out of their holes to a world that was theirs. Those mammals eventually evolved into primates and then evolved into us. We would probably not exist if it weren’t for the meteor killing our worst predators. Now just think, if we go extinct, what animals will follow after us? Who knows, maybe a species smarter than us? A species that has all of our virtues and little of our flaws. They would probably be able to dig up our fossils. They would probably even figure out that we were advanced by the synthetic plastics that would most likely still exist by then. They would be very confused.