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Intro to Wave PropertiesYaama I'm Jack Evans and you're watching BTN. Here's what's coming up. We uncover the story behind this famous photo, learn about First Nations seasons and find out the history of Book Week. What is Statehood? Reporter: Tatenda Chibika INTRO: But first, the Prime Minister Anthony Albanese has announced that Australia will join other countries in recognising Palestine as an independent state. So, what does that mean? Tatenda found out. Anthony Albanese, Prime Minister: Australia will recognise the state of Palestine. Australia will recognise the right of the Palestinian people to a state of their own. We will work with the international community to make this right a reality. Tatenda Chibika, Reporter: That's the moment our Prime Minister said Australia would recognise Palestine as an independent state at the upcoming United Nations General assembly next month. It's something other countries, including France and Canada, have said they'll be doing too. So, what does that mean exactly? To be considered an independent state under international law a place needs to have its own land or territories with defined borders, it needs to have people who permanently live there, have a working government and it has to be able to talk and make deals with other countries. Once a place meets all those rules, it can ask to be recognised by other independent states and countries. But a big step in becoming an independent state is being fully recognised by the United Nations. To do that you first need to get approval from at least nine members of the UN's Security Council. That's a group of countries responsible for maintaining international peace and security. But even then, that tick of approval can still be blocked by one of the Security Council's five permanent members Russia, China, the UK, the US and France. If the Security Council approves, the decision then goes to the UN's General Assembly where at least two thirds of the UN's 193 members have to agree to make it official. Yeah, it's a pretty complex process which is why we've only seen a handful of countries recognised by the UN in recent years like South Sudan and Montenegro. Others like Kosovo are only 'partially' recognised which means they have some recognition but not enough to become a full member state at the UN. Right now, Palestine is recognised by more than 140 countries — that's more than two thirds of the UN General Assembly. So, why hasn't it become a UN member state yet? Well, it came pretty close last year when 12 members of the Security Council voted in favour of it. VANESSA FRAZIER, AMBASSADOR OF MALTA, APRIL 2024 UNSC PRESIDENT: I shall now put the draft resolution to the vote. But the US, a close ally to Israel, used its special powers to block Palestine from becoming a member state. VANESSA FRAZIER: Those against? At the time, the U.S said Palestine and Israel needed to come to an agreement on their own first. Throughout the years, there have been attempts to figure out a way for both Palestine and Israel to exist peacefully alongside each other but that hasn't happened yet. And now Israel has said that recognising Palestine as an independent state would be rewarding Hamas the group in charge of Gaza which was responsible for the terror attacks on October 7th, 2023. But the Palestinian Authority which governs parts of the West Bank says Hamas won't have a role in any future state of Palestine which will exist peacefully alongside Israel. Australia, like the US, had previously said that it wanted Israel and Palestine to figure out things by themselves first but because of how the war has been going the Australian government is worried that if it continues to wait, there might not be a Palestinian state to recognise. ANTHONY ALBANESE, PRIME MINISTER: There has been too many lives lost, both Israeli's and Palestinians and the world is saying we need a solution to this conflict, we need to end the cycle of violence and the way to do that is to have a two-state solution. News Quiz Russia's President Vladimir Putin stepped foot on American Soil for the first time in a decade to meet with US President Donald Trump. What state did they meet in? Alabama, Alaska or Arizona?It's Alaska. The two leaders met to discuss a way to end the war in Ukraine but weren't able to make any final agreements. DONALD TRUMP, US PRESIDENT: There were many, many points that we agreed on. Most of them, I would say, a couple of big ones, that we haven't quite got there, but we've made some headway. There's no deal until there's a deal. A lot of people criticised the two world leaders for not including Ukraine's president Volodymyr Zelenskyy in the meeting. But that didn't seem to worry Mr Trump who said the meeting was a success and Mr Putin even invited the US President to meet up again in Russia. DONALD TRUMP: We'll see you again very soon. Thank you very much, Vladimir. VLADIMIR PUTIN, RUSSIAN PRESIDENT: Next time in Moscow. DONALD TRUMP: Oh, that's an interesting one. No, no, no. I'll get a little heat on that one. Last week thousands of people marked the 80th anniversary of VJ Day. What does VJ Day commemorate? The victory of Allied forces in Europe, the surrender of Japan and the end of World War II or the dropping of the first atomic bomb? VJ Day or Victory over Japan day commemorates the surrender of Japan and the end of World War II on the 15th of August 1945. Around the world, and here in Australia, people marked the anniversary with ceremonies remembering those who fought in the war. REPORTER: Who will you be remembering today? VETERAN: Oh, a lot of fellows that I knew that never made it home. Scientists in the UK have created toothpaste that includes which of these ingredients? Hair, eye lashes or fingernails? Yeah, they're all a bit random and gross but the answer is hair. According to scientists from King's College in London, hair could be the key to good oral health because it contains a protein called Keratin which they say when mixed with saliva forms a crystal-like protective coating similar to enamel. And Swifties rejoice because Taylor Swift has announced her 12th Studio album. It's called life of a show what? Is it show pony, show girl or show bag? It's Life of a Showgirl and it'll be released October 3rd. Vincent Lingiari Reporter: Joseph Baronio INTRO: Now to this very famous photograph. It was taken 50 years ago and depicts a really significant moment in Australian history. Joe found out about the story behind it. On the 16th of August 1975, this famous photo was taken. It shows the former Prime Minister Gough Whitlam pouring sand into the hand of Aboriginal leader Vincent Lingiari. A simple gesture that symbolised handing the land at Wave Hill in the Northern Territory back to the Gurindji people. But the journey to get there was far from simple. It started back in the 1960s. At the time, Wave Hill was the biggest cattle station in the world, controlled by British landowner Lord Vestey. The Gurindji people, who had lived on the land for generations, worked for Vestey, but they weren't paid fairly, and conditions were tough. NEWS REPORTER: The station's 100 aboriginal stockmen, with their 100 dependents, are camped in the dry bed of the Victoria River with little shade from 90-degree heat, dust and flies. Eventually, Gurindji leader Vincent Lingiari said it was time to act. VINCENT LINGIARI: I said, "What was it before Lord Vestey born and I was born?" It was blackfella country. So, on August 23rd, 1966, Mr Lingiari and his fellow Aboriginal workers went on strike. It became known as the Wave Hill Walk Off. They moved their camp away from the Wave Hill station to a sacred site called Daguragu on Wattie Creek. They wanted to set up their own cattle station, and said they wouldn't move until their land was returned to them. For years, petitions and negotiations went on between the Gurindji people, the NT Administration, and the Australian Government in Canberra. CLAPPERS: 31. 32. 33. DAVID QUINN, ABSCOL: Well, it's basic justice that their land is recognised. PROTESTORS: Equal rights! As the news spread across the country, thousands of Aussies joined the campaign, including the leader of the Labor Party, Gough Whitlam, who made this promise during his 1972 election campaign. GOUGH WHITLAM: We will legislate to give Aborigines land rights. Not just because their case is beyond argument, but because all of us as Australians are diminished, while the Aborigines are denied their rightful place in this nation. Later that year, Gough Whitlam became Prime Minister. (Song From Little Things Big Things Grow, Song by Kev Carmody and Paul Kelly, 1993) From little things big things grow,from little things big things grow… But it wasn't until 1975, 9 years after the Wave Hill Walk Off started, that he followed through with his promise. Eight years went by, eight long years of waiting'Til one day a tall stranger appeared in the landAnd he came with lawyers and he came with great ceremony GOUGH WHITLAM: I solemnly hand to you these deeds as proof in Australian law that these lands belong to the Gurindji people. And through Vincent's fingers poured a handful of sandFrom little things big things grow 50 years on, and The Wave Hill Walk Off is seen as a pivotal moment in Australia's history. It led to significant legal and social changes for First Nations people, which is something many agree is worth celebrating. First Nations Seasons Reporter: Saskia Mortarotti INTRO: Recently, Melbourne's Lord Mayor suggested ditching the four-season calendar that most of us are familiar with and adopting a six-season Wurundjeri calendar instead saying it gives a better description of what the weather's actually like there. Sas found out more about the different seasonal calendars used by First Nations people. SASKIA MORTAROTTI, REPORTER: Right now, in most of the country, it's pretty cold. COLD GIRL: Think of somewhere warm. What? It's 32 degrees in Darwin in the middle of winter? But ah, yeah. There are some places where it's, well, quite warm. Which makes you wonder whether the weather actually matches the seasons. You see, Australia is pretty big, and we have lots of different weather patterns. Which is something First Nations people have tracked for thousands of years with their own seasonal calendars. KARL WINDA TELFER, CULTURAL CREATIVE KANYANYAPILLA: Why have we got four seasons when you know that don't make any sense here. It doesn't relate to the country here. This is Karl Telfer. He's an artist and storyteller who produced the Kuri Kurru exhibition at the Museum of Discovery in Adelaide that explores the 6 different seasons of the Kaurna Meyunna. SASKIA MORTAROTTI: So, how do you know when you're in one of those six seasons? KARL WINDA TELFER: Well, there are stars that rise. So, you know, there are certain stars, like in Parnatti, for example. There's a star called Parna, and we know what that star is. So, that talks to us about, okay, the time now is going to be cold on the ground. First Nations calendars like the Kaurna one don't just tell us what's happening with the weather; they're also used to track when certain plants and animals are around. KARL WINDA TELFER: It teaches you about what plants you can, you know, what you can eat what you can't and all that what is ready certain times a year and fruit everything, bird shows you the right time to eat the fruit, perfect time, if you try and go get them the next week they're gone. Karl says we can also use these calendars to see how the environment has changed over time. KARL WINDA TELFER: Kudlilla is the season we're in now and Kudlilla that talks about like the rain but we're not having enough rain these days, well, these times. And this is due to climate and the climate changing. There are many different First Nations seasonal calendars around the country. Like Ngan'gi calendar from the Northern Territory which has 13 seasons that follow the life cycle of the native spear grass. Or the Wurundjeri Calendar in Victoria which has 6 seasons. And recently, Melbourne's Lord Mayor, Nicholas Reece, said Melbourne, or Naarm, would be better off adopting the Wurundjeri calendar because it's more in tune to what's happening with the weather. Something many, including Karl, think we should be doing right across the country. KARL WINDA TELFER: I'm talking about the English four seasons. So, this is totally different systems that we're talking about and weather patterns and currents and all sorts of different things, because it's the sea country too. So, my question is, well, why do we have that? If that doesn't work, you know? Quiz How many seasons are there in the Tiwi Island Calendar? 1, 2 or 3? It's 3, although they also have 13 minor seasons. Book Week Reporter: Wren Gillett INTRO: This week, kids across Australia have been dressing up as their favourite characters to celebrate Book Week. Wren finds out why Book Week began 80 years ago and why it's still important today for getting young Aussies into reading. STUDENT: I read an hour every night, maybe even two hours some nights. STUDENT: My favourite book series are the Harry Potter series and the Keeper of the Lost City series. STUDENT: Probably Bad Guys and Weirdo. STUDENT: I like the Amulet, I've been reading that. STUDENT: I love reading Dork Diaries and Exploding Endings. Whether it's Fantasy, mystery, history — whatever you're into. Book week is a time to celebrate, well, books. STUDENT: Me and my friends are dressing up as Inside Out. STUDENT: I was thinking SpongeBob. STUDENT: I'm dressing up as Winnie the Pooh and it's just a fun way to express what kind of books you like. And guess what, book week has actually been a thing for many, many years. WREN GILLETT, REPORTER: Once upon a time, in a land not so far away, literacy lovers noticed a problem. The year was 1945. The second World War had just ended, and kids were mainly reading books from overseas, in particular the UK. Because, at the time, there weren't many Aussie authors writing books for children. WREN GILLETT: So, a group of passionate teachers, librarians, booksellers, publishers, and book-loving volunteers, decided to create what we now know as The Children's Book Council of Australia. Familiar logo, right? Together, they launched book week, all in an effort to get Aussie kids' reading more. And it seemed to work. The 1960s saw a boom in Australian children's books being published. REPORTER: How many books do you read a week? STUDENT: Well, it really depends on the week. If there's exams, I might read only one or two. But if there's no exams and if I've got plenty of time, I might read up to five or six. WREN GILLETT: But today, it's a slightly different story. Studies show that less than one in five eight to 18-year-olds are reading in their free time, and that only one in three actually enjoy reading for fun. WREN GILLETT: Why do you reckon we're seeing this trend? STUDENT: People are getting sucked into screens and they're like spending hours just scrolling through TikTok and stuff, and they're getting so attached to it that they don't feel the need to pick up books and read them. Yeah, there's a lot of different things competing for our attention these days, but many think books are still worth our time. PETER HELLIER, AUSSIE COMEDIAN AND AUTHOR: Books are the exact opposite of boring. And if you think they're boring, I'm sorry, but you're wrong. This is Peter Hellier, he's a pretty famous Aussie comedian, actor, and the author behind these books. And he's just released another one called Detective Galileo, about a trail horse who dreams of solving crimes. PETER HELLIER: He joins the police force and quickly finds out that the horses don't actually solve the crimes, it's the police officers who solve the crime. So he promptly gets thrown out of the force and begins his own detective agency, which I'm reliably told is the only detective agency in the world run by a horse. Peter actually started writing books when he was a kid. PETER HELLIER: I started writing when I was six, seven, eight years old. In fact, I started my own publishing company called Better Books. And I would write these books, and then I would get a parent or one of my parents or teachers to type them up. And I would read them in front of the class. And, you see, each has the logo, the Better Books logo, there it is — the famous Better Books logo. WREN GILLETT: You weren't mucking around. PETER HELLIER: There all on all of them. There we go. There we go. Many, Including Peter, say there's plenty to get from a good book. They help us learn new words and phrases, get a better understanding of the world around us, and strengthen our imaginations. PETER HELLIER: Books can take you absolutely anywhere. They can take you to countries that you never dreamed about going. Countries that exist, countries that don't exist. Reading just makes the world a much bigger place. It's why for the past 80 years, schools around the country have been taking part in book week. STUDENT: Reading is a place where you can have your own world just to yourself. STUDENT: It's like watching a movie inside your head, but you can choose how it goes. STUDENT: Picking up a book is a good idea, maybe you should start with something that you're interested with and then you can start exploring from there. Quiz What is the title of the book that took out this year's Book of the year Award for younger readers? It's Laughter is the Best Endingby Maryam Master. Some other winners included I'm not really here by Gary Loneborough which took out book of the year for older readers and best picture book went to The Truck Cat, by Deborah Frenkel. Sport Australia's men's national basketball team — the Boomers — have won their third Asia Cup in a row, with an epically narrow victory over China. COMMENTATOR: It is Australia who are celebrating! China started strong, leading 25-17 at quarter time. But Aussie Xavier Cooks led a fierce comeback, shooting 30 points and collecting nine rebounds, earning him the title of MVP. And there seriously couldn't have been a tighter finish. Just as the final buzzer went off, China missed a shot that would have won them the game, leaving Australia with a 90-89 victory. COMMENTATOR: An unbelievable finish. The 2025 AFLW season kicked off last week, and so did a new trick. Yeah, 19-year-old Ash Centra from Collingwood, pulled out this move in the warm-up before their season-opener to Carlton, and since then, a lot of people have been trying to do it, with some success, kind of? FOOTY PLAYER: No, I'm not doing it on camera. But despite the epic warmup, Carlton did end up beating Collingwood by 24 points. Now, the moves from these athletes in China weren't quite so graceful but give 'em a break, okay, they're robots. For the first time ever, humanoid robots from all over the world, competed in their very own games, which featured, soccer, boxing, running, and ahh, lots of falling over. Lots. Luckily though, they did bring their own cheer squad. Young Rapper Reporter: Rylie INTRO: Finally, we're going to meet another winner of this year's Heywire competition — which asks young people in regional areas to share their stories. Rylie's going to tell us how music helped to transform his life. Check it out. Mum and I were homeless. We lived at a caravan park, in motels and tents around Warrnambool. It wasn't pretty. I'm First Nations, and I remember feeling like, my own country is failing me right now. So, we camped right along here. I remember pitching a tent right here and this was actually around the same time I started to get into music which was a good way for me to have something to look forward to. I was raised by the SoundCloud era, listening to a lot of trap music. When I was in school, I'd rap along to songs by Juice World, then I started to make my own. My first track was recorded on my phone. It was bad but a lot of fun to make. Some kids in my school heard it and shamed me. That put me off music for the next couple of years, until a friend of mine bought a microphone and encouraged me to give it another go. There was something about that mic and the energy of the crew around me that gave me confidence. It lit a fire in me. Over time, I was able to focus my flow. My songs are about escapism, living the life, being a success. I rap about stuff that takes me to a better place in my head. I'm manifesting my future. My stage name is Hundo Milli, it's short for hundreds of millions. Money's not really the end goal; it's more about having the freedom to dream big. Mum taught me to never stop believing. Even when times were tough, she kept pushing for us to get housing and eventually we did. We're some of the lucky ones. Today, I'm in a Melbourne studio recording my next single. I remember living in my tent dreaming about this very moment and now I'm here, doing what I love. Ain't nothing going to stop me. Closer Well, that's all we've got for you today, but we'll be back before you know it. In the meantime, you can head to our website, there's plenty to see and do. You can also catch Newsbreak every weeknight and there's BTN High for all you highschoolers out there. Have an awesome week and I'll see you next time. Bye.Marine and Coastal Processes.What are the hazards that usually occur along marine and coastal areas? Coastal processes, such as waves, tides, sea level changes, crustal movement, and storm surges will result to coastal erosion, submersion, and saltwater intrusion. Coastal Erosion. Coastal erosion is the wearing down of the coastlines by the movement of wind and water. It is not a constant process; instead, the rate of erosion depends on other events such as cyclones. When cyclones occur along coastal areas, the winds and waves carry the sediment away from the shoreline. Shorelines play an important role to society. They are used in transportation, fishing, and tourism. Therefore, preventing coastal erosion is of utmost priority. There are three main classifications of stabilizing the shoreline: hard stabilization, soft stabilization, and retreat. 1. Hard stabilization is done by building structures that will slow down the erosion on areas that are prone to erosion. Examples of hard stabilization structures are jetties, sea walls, and breakwaters. Though they may slow down the erosion in one area, it may hasten the erosion in other areas. 2. Soft stabilization includes the process of beach nourishment, wherein sand from an offshore location is brought to an area with a receding shoreline. It does not make use of structures like the ones used in hard stabilization. 3. Retreat is the option taken by residents near areas where coastal erosion is already severe. At this point, the authorities no longer attempt to save the shoreline but rather limit the amount of human interference in the area. Submersion. Coastal erosion happens because of the interaction of the winds and waves on the shoreline. Submersion, on the other hand, happens because of the changes in the sea level, specifically, when it rises dangerously above the normal level. This is all due to the increase in the global temperature, which, in turn, melts the glacial deposits and increases the overall sea level. Another factor that may cause submersion is the vertical movement of the plates. Landmasses can be uplifted, which can also cause changes in the sea level. It can also be caused by tsunamis and storm surges. Submersion will most likely occur in reclaimed lands. These are the areas that were originally part of oceans, riverbeds, or lakebeds. They are low-lying flatlands, so even a small rise in sea level can cause great damage on the land. To prevent this from happening not only in reclaimed lands but also in coastal areas, a hard stabilization technique is used. Sea walls are built along the coastline to protect the land from being easily flooded. Aside from sea walls, dikes can also help prevent flooding. The government can also upgrade the infrastructures built in coastal areas, regenerate mangroves, or relocate the people. There are also other proposed strategies to mitigate coastal submersion, such as imposing of setback policies and construction regulations and creating adaptive plans for coastal management. Saltwater Intrusion. In coastal areas where there is an interaction between saltwater and fresh water, saltwater intrusion is one of the hazards that are evident in that area. Saltwater intrusion is the movement of saltwater into the freshwater aquifer. The natural flow is that the fresh water, which is less dense, moves towards the denser saltwater. But if the fresh water is being withdrawn faster than it is being replenished, then there will be a change in pressure and saltwater intrusion will occur.There are a few ways of preventing saltwater intrusion. One is to stop using the well where fresh water has been depleted and let the groundwater replenish naturally via the water cycle. The other method is to build two wells: a pumping well-built farther inland and an injection well-built closer to the coast. Using the injection well, fresh water is pumped into the aquifer to prevent the saltwater from intruding. The different marine and coastal hazards often occur in the Philippines, being an archipelago with the longest coastline. Manila Bay is one of the coastal areas of the Philippines that is facing various threats from both natural and anthropological causes. Saltwater intrusion occurs due to uncontrolled withdrawal of groundwater to be used by residential, commercial, and industrial areas built around the bay. It is also frequently flooded due to poor drainage systems and improper disposal of waste. Since Manila Bay is shared by four coastal provinces, four noncoastal provinces, and the National Capital Region, each local government unit and national agencies need to collaborate in planning, developing, and managing its marine and coastal resources. And it is not only Manila Bay but other parts as well, for as long as they are in coastal areas, hazards will mostly likely occur if not immediately addressed.Into the Sea What Is Erosion? Have you ever made a sand castle at the beach? You must pick a good spot for it. If it is too close to the water, waves will quickly wash it away. Ocean waves and wind can also wash away land. They can change the shape of an island, which is land circled by water. When wind and water change the shape of Earth, it is called erosion. Waves are the biggest cause of erosion at the beach. Ocean waves are always active and moving onto the shore. They carry the sand away bit by bit. Strong waves are one of the properties of big storms. These waves explode as they crash onto the beach. Storm waves can move a lot of sand quickly. Erosion of Beaches. Some people build houses near the ocean. Waves take away the sand between the houses and the sea. As the beach disappears, the water gets closer to houses and other solid buildings on the beach. Some buildings can even be washed away. Erosion of Rocks. Erosion also happens on steep, rocky cliffs or sharp slopes. First, waves smash into the bottom of the cliffs. Then they carry away tiny pieces of rock. Over time, many small pieces of rock wash away from the bottom of the cliff. This makes the top of the cliff weak.The cliff can crumble and fall into the sea. Stopping Erosion. Some local communities work to stop erosion to nearby beaches. These towns have built sea walls of large boulders or rocks. The rocks are placed in a row in the sea. When waves hit the sea wall, they slow down. Then the waves can't pull sand away.Some towns make rules about buildings on the beach. New buildings must be far from the water. Then they won't wash away like a sand castle.How to Stop Avalanchesnow with explosives, or by erecting snow fences. Explosives Explosives are primarily used to prevent avalanches, especially at ski resorts where other methods are often impractical. Maintenance staff from the ski resort travel to potential avalanche areas and areas with steep slopes. First, they measure the depth of the snow and its quality. They want to check for hard, loose, wet or icy snow layers. If an area is considered dangerous, small explosives are fired into the side of the steep terrain. The explosion loosens the top layer of snow, which tumbles harmlessly down the mountainside. But using explosives is costly and dangerous. Some researchers are currently experimenting with the cheaper and safer method of using ultrasonic sound waves that shock the snow into falling, averting an avalanche and saving lives. Snow Fences It is very common to put up snow nets or snow fences. These nylon nets or wooden and steel fences are placed at the top of slopes. They prevent the buildup of snow on the downwind side, thereby lessening the chance of a slab avalanche. Beacons and Radio Devices Fortunately, there are companies that specialize in making rescue beacons. These are small electronic devices that send out a radio signal to search and rescue crews. Most people who venture into the backcountry carry some sort of beacon or GPS device. They can help locate a buried victim up to 80 meters away. However, these beacons and GPS devices only send out a signal if the victim turns it on. Often, the victim is too injured to think clearly and press the 'on button.' If search and rescue crews do not quickly reach the victims, the skiers will not be discovered in time. Surviving an Avalanche If you are ever caught in an avalanche, the chances are slim that you will survive. If you are not killed instantly, you only have a short time (15~35 minutes) before your oxygen runs out. Take off your ski, boots and poles. Use a swimming motion to claw your way to the surface. Often people do not know which way is up or down. The effect of this is disorientation. It is not uncommon for avalanche victims to dig in the wrong direction. With proper precautions, both skiers and ski resorts can avoid the tragedy of an avalanche.How to Stop Avalanches ToB A major concern of ski resorts is avalanche control. Most avalanches occur outside the boundaries of the regular groomed ski runs. But each year, skiers and trekkers on snowshoes go into these remote areas where most avalanches occur. There are two primary ways to prevent avalanches-by blasting the snow with explosives, or by erecting snow fences. Explosives Explosives are primarily used to prevent avalanches, especially at ski resorts where other methods are often impractical. Maintenance staff from the ski resort travel to potential avalanche areas and areas with steep slopes. First, they measure the depth of the snow and its quality. They want to check for hard, loose, wet or icy snow layers. If an area is considered dangerous, small explosives are fired into the side of the steep terrain. The explosion loosens the top layer of snow, which tumbles harmlessly down the mountainside. But using explosives is costly and dangerous. Some researchers are currently experimenting with the cheaper and safer method of using ultrasonic sound waves that shock the snow into falling, averting an avalanche and saving lives. Snow Fences It is very common to put up snow nets or snow fences. These nylon nets or wooden and steel fences are placed at the top of slopes. They prevent the buildup of snow on the downwind side, thereby lessening the chance of a slab avalanche. Beacons and Radio Devices Fortunately, there are companies that specialize in making rescue beacons. These are small electronic devices that send out a radio signal to search and rescue crews. Most people who venture into the backcountry carry some sort of beacon or GPS device. They can help locate a buried victim up to 80 meters away. However, these beacons and GPS devices only send out a signal if the victim turns it on. Often, the victim is too injured to think clearly and press the 'on button.' If search and rescue crews do not quickly reach the victims, the skiers will not be discovered in time. Surviving an Avalanche If you are ever caught in an avalanche, the chances are slim that you will survive. If you are not killed instantly, you only have a short time (15~35 minutes) before your oxygen runs out. Take off your ski, boots and poles. Use a swimming motion to claw your way to the surface. Often people do not know which way is up or down. The effect of this is disorientation. It is not uncommon for avalanche victims to dig in the wrong direction. With proper precautions, both skiers and ski resorts can avoid the tragedy of an avalanche.When television first started, the system of broadcasting was analogue. This meant that a TV aerial received radio waves from the TV companies. These transformed into sound and images on the TV screen. At the time, the system was revolutionary, but it wasn't perfect. It couldn't transmit many channels and the quality of the pictures was sometimes poor because of interference. For a long time there was only analogue I, but at the end of the 1990s, digital television arrived. Digital TV doesn't use radio waves. Instead, it converts sound and images into binary code. This is a computer language which only consists of zeros and ones and broadcasters can use it to send a lot of information very quickly. This digital information arrives at a TV via an aerial, a cable, a satellite dish, or broadband. Then a decoder converts the information back to sound and images. Decoders are either inside a TV or computer, or in a separate box which is connected to it. Digital broadcasting is much better than the analogue system. There are a lot more channels because the TV companies can transmit much more information. The quality of the images and sound is much higher because there is less interference. Picture quality is even better on a high definition TV (an HDTV) than on a standard TV, so viewers can enjoy cinema-quality pictures in their own home.What do an ancient Greek philosopher and a 19th century Quaker have in common with Nobel Prize-winning scientists? Although they are separated over 2,400 years of history, each of them contributed to answering the eternal question: what is stuff made of? It was around 440 BCE that Democritus first proposed that everything in the world was made up of tiny particles surrounded by empty space. And he even speculated that they vary in size and shape depending on the substance they compose. He called these particles "atomos," Greek for indivisible. His ideas were opposed by the more popular philosophers of his day. Aristotle, for instance, disagreed completely, stating instead that matter was made of four elements: earth, wind, water and fire, and most later scientists followed suit. Atoms would remain all but forgotten until 1808, when a Quaker teacher named John Dalton sought to challenge Aristotelian theory. Whereas Democritus's atomism had been purely theoretical, Dalton showed that common substances always broke down into the same elements in the same proportions. He concluded that the various compounds were combinations of atoms of different elements, each of a particular size and mass that could neither be created nor destroyed. Though he received many honors for his work, as a Quaker, Dalton lived modestly until the end of his days. Atomic theory was now accepted by the scientific community, but the next major advancement would not come until nearly a century later with the physicist J.J. Thompson's 1897 discovery of the electron. In what we might call the chocolate chip cookie model of the atom, he showed atoms as uniformly packed spheres of positive matter filled with negatively charged electrons. Thompson won a Nobel Prize in 1906 for his electron discovery, but his model of the atom didn't stick around long. This was because he happened to have some pretty smart students, including a certain Ernest Rutherford, who would become known as the father of the nuclear age. While studying the effects of X-rays on gases, Rutherford decided to investigate atoms more closely by shooting small, positively charged alpha particles at a sheet of gold foil. Under Thompson's model, the atom's thinly dispersed positive charge would not be enough to deflect the particles in any one place. The effect would have been like a bunch of tennis balls punching through a thin paper screen. But while most of the particles did pass through, some bounced right back, suggesting that the foil was more like a thick net with a very large mesh. Rutherford concluded that atoms consisted largely of empty space with just a few electrons, while most of the mass was concentrated in the center, which he termed the nucleus. The alpha particles passed through the gaps but bounced back from the dense, positively charged nucleus. But the atomic theory wasn't complete just yet. In 1913, another of Thompson's students by the name of Niels Bohr expanded on Rutherford's nuclear model. Drawing on earlier work by Max Planck and Albert Einstein he stipulated that electrons orbit the nucleus at fixed energies and distances, able to jump from one level to another, but not to exist in the space between. Bohr's planetary model took center stage, but soon, it too encountered some complications. Experiments had shown that rather than simply being discrete particles, electrons simultaneously behaved like waves, not being confined to a particular point in space. And in formulating his famous uncertainty principle, Werner Heisenberg showed it was impossible to determine both the exact position and speed of electrons as they moved around an atom. The idea that electrons cannot be pinpointed but exist within a range of possible locations gave rise to the current quantum model of the atom, a fascinating theory with a whole new set of complexities whose implications have yet to be fully grasped. Even though our understanding of atoms keeps changing, the basic fact of atoms remains, so let's celebrate the triumph of atomic theory with some fireworks. As electrons circling an atom shift between energy levels, they absorb or release energy in the form of specific wavelengths of light, resulting in all the marvelous colors we see. And we can imagine Democritus watching from somewhere, satisfied that over two millennia later, he turned out to have been right all along.