High up in the Himalayas, between Nepal and Tibet, stands a mountain so tall it reaches into the “death zone,” where temperatures can drop to minus 60 degrees Celsius, and the air has only a third of the oxygen we need. This mountain is Mount Everest, the highest point on Earth—or is it? Everest is currently measured at 8,848.86 meters tall, but measuring mountains is more complicated than it seems because the Earth isn’t perfectly round, and its crust is always moving.
In the 18th century, Mount Chimborazo in Ecuador was thought to be the tallest mountain. Then, in 1808, Dhaulagiri took the title until 1847, when Everest was officially recognized as the tallest. But the story doesn’t end there. How we measure a mountain depends on how we define it, and there’s no universal rule for what makes a mountain. Over the years, Everest’s height has changed due to different measuring techniques, technological advancements, and the fact that mountains are not as stable as they appear.
Mountains are formed by the movement of the Earth’s crust, which is broken into plates like a giant jigsaw puzzle. These plates can collide, grind, or pull apart, changing a mountain’s height over time. Imagine tectonic plates floating on the molten mantle like logs on a river. Heat from the Earth’s core causes molten rock to rise, cool, and sink, moving the plates. Sometimes, denser crust sinks under lighter crust, creating pressure that forms volcanic mountains. Other times, plates collide, crumpling rock and pushing it skyward, forming ranges like the Himalayas. Everest and its neighbors began forming when the Indian plate collided with the Eurasian plate 40 to 50 million years ago, and this activity continues today.
Mountains also form where plates pull apart, mostly underwater, like at the Mid-Atlantic Ridge, the longest mountain range on Earth. But Earth isn’t the only place with mountains. Some peaks in space are even taller. For example, a crater ridge on the asteroid Vesta is about 19 kilometers high, and Olympus Mons on Mars is about 22 kilometers high. If Olympus Mons were on Earth, you’d need a space suit to reach its summit!
Why can’t Earth’s mountains reach such heights? The processes that create mountains can also destroy them. Weather, rivers, rock slides, and glaciers erode mountains. If a mountain becomes too heavy, it starts sinking and melting from the bottom, limiting its height. In 2015, a 7.8 magnitude earthquake in Nepal made some Himalayan peaks shorter by up to 60 centimeters. However, Everest continues to grow as the Indian plate pushes against the Eurasian plate. But will it always be the tallest? Nanga Parbat in Pakistan is growing faster and might surpass Everest in a few hundred thousand years.
Measuring mountains involves more than just finding the top. You also need to determine the bottom, which isn’t straightforward. For instance, more than half of Hawaii’s Mauna Kea is underwater. While about 4,200 meters are above water, from base to summit, it’s over 10,000 meters tall—20% taller than Everest. If we measure from base to summit on land, Denali takes the title. Everest is usually measured from sea level, but sea level isn’t uniform due to variations in Earth’s crust density and gravity.
Scientists use a mean sea level to measure mountains, but measuring from the Earth’s center gives different results. Mount Chimborazo is actually farther from the Earth’s center than Everest, despite being shorter by sea level standards.
Could GPS solve this mystery? Satellites can measure how far the top of a mountain is, but determining the bottom is tricky. GPS relies on an imaginary model of the Earth called the ellipsoid, which differs from mean sea level and doesn’t account for gravity variations.
Currently, the accepted method is to measure a mountain’s height above mean sea level, which gives Everest the title of tallest. However, other mountains have strong claims. To truly identify the tallest mountain, we first need to agree on where a mountain starts.
Stay curious!
Imagine you are a scientist tasked with determining the tallest mountain on Earth. Research different methods of measuring mountains and present your findings to the class. Discuss the pros and cons of each method and decide which one you believe is the most accurate. Be prepared to defend your choice!
Create a 3D model to demonstrate how tectonic plates move and form mountains. Use materials like clay or cardboard to represent the Earth’s crust and mantle. Show how plates collide, pull apart, or slide past each other, and explain how these movements contribute to mountain formation. Present your model to the class and explain the process.
Conduct an experiment to understand how erosion affects mountains. Use a small pile of sand or soil to represent a mountain and simulate erosion with water, wind, or ice. Observe and record how the “mountain” changes over time. Discuss how erosion impacts the height and shape of real mountains.
Research mountains on other planets and celestial bodies, such as Olympus Mons on Mars. Compare these extraterrestrial mountains to those on Earth in terms of height, formation, and conditions. Create a poster or presentation to share your findings with the class, highlighting the differences and similarities.
Take a virtual tour of Mount Everest using online resources or virtual reality. Explore the different camps, routes, and challenges climbers face. Write a short essay or create a video diary about your virtual climbing experience, including what you learned about the mountain’s geography and the difficulties of measuring its height.
Here’s a sanitized version of the provided YouTube transcript:
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Between Nepal and Tibet in the Himalayas sits a mountain so tall that it stretches into what’s known as the death zone. Temperatures here can hit minus 60 degrees Celsius. The air contains only a third of the oxygen we need to survive. And yet, thousands of people have braved these harsh conditions to stand here at the highest point on the planet. Or is it? Everest checks in at 8,848.86 meters tall today. But we still don’t really know if that’s right. Because on a planet that isn’t perfectly round, wrapped in a crust that keeps moving, measuring a mountain turns out to be more complicated than you might think.
Hey smart people, Joe here. To someone alive in the 18th century, Mount Chimborazo in Ecuador was considered the tallest mountain on Earth. Then in 1808, that honor shifted to Dhaulagiri, until 1847, when Everest was measured as the officially verified tallest mountain on Earth. So it’s settled then, right? Well, it’s not that simple. How you measure a mountain depends on how you define what a mountain is. Surprisingly, there’s no universally accepted rule for what constitutes a mountain. Even since the first official measurement of Everest almost 200 years ago, its height has changed many times. Some of that is due to different measuring techniques, advancements in technology, and the fact that mountains aren’t as unchanging as they appear.
Before we tackle that climb, we need to talk about how mountains are formed. You probably learned in school that the Earth’s crust is broken up into plates, like a giant moving jigsaw puzzle. Mountains mostly form where neighboring plates are colliding, grinding, or spreading apart. As these processes occur, they can change a mountain’s height depending on when you measure it.
You might imagine tectonic plates floating on the molten mantle like logs on a river, and that’s somewhat accurate. There are huge currents deep underground caused by heat from the core rising up and carrying molten rock towards the surface, then cooling and sinking back down. But that’s not the only reason the plates move. In some places, denser crust sinks under lighter crust, pulling the rest of the crust behind it. After that sinking crust melts, it can build pressure until a volcanic mountain forms. In other areas, plates meet like a slow geological collision, crumpling up the rock and pushing it towards the sky. This is how some of Earth’s biggest mountain ranges formed. Everest and the rest of the Himalayas began growing when the Indian plate collided with the Eurasian plate about 40 to 50 million years ago, and that tectonic activity is still ongoing.
Mountains can also form where plates pull apart, which mostly happens underwater, like at the Mid-Atlantic Ridge, the longest mountain range on Earth. These processes occur everywhere we find mountains, not just on Earth. Some extraterrestrial peaks dwarf ours. For example, a crater ridge on Vesta, a large asteroid, is around 19 kilometers high, and Olympus Mons on Mars is about 22 kilometers high. If Olympus Mons were on Earth, you’d need a space suit to visit its summit.
So why can’t Earth mountains reach those heights? For starters, the processes that create mountains can also destroy them. Massive amounts of rock are eroded away by weather, rivers, rock slides, and glaciers. Additionally, if a mountain becomes heavy enough, it starts sinking, essentially melting from the bottom, which limits its height.
In 2015, a magnitude 7.8 earthquake in Nepal made some peaks in the Himalayas instantly shorter by up to 60 centimeters. However, Everest is still growing taller each year as the Indian plate continues to collide with the Eurasian plate. Will it hold the title of tallest Earth mountain forever? Maybe not. Nanga Parbat in Pakistan is growing faster than Everest and might surpass it in the next couple hundred thousand years.
Because of factors like weight, erosion, and the unique way mountains are measured, there’s likely a maximum height that an Earth mountain can achieve, and those super peaks in the Himalayas are close to that limit. When it comes to the title of tallest mountain, Everest only wins if we measure mountains in a specific way. Finding the top is only half the equation; you also need to determine the bottom, which is not as straightforward as it seems.
More than half of Hawaii’s Mauna Kea is submerged. While about 4,200 meters are visible above water, from base to summit, it’s actually more than 10,000 meters tall—about 20% taller than Everest. If we consider base-to-summit measurements on land, then Denali takes the title. Everest is typically measured from sea level, which is tricky too, as sea level isn’t uniform due to variations in Earth’s crust density and gravitational forces.
Scientists create a mean sea level to measure mountains against. Some may find this complicated, but measuring mountains by their distance from the center of the Earth yields different results. The maximum distance from Earth’s center is actually Mount Chimborazo, which is more than two kilometers farther from the center than Everest’s peak, despite being shorter by sea level standards.
Could we settle this elevation uncertainty using GPS? While satellites can measure how far the top of a mountain is, they also face challenges in determining the bottom. GPS measurements rely on an imaginary mathematical model of the Earth called the ellipsoid, which differs from mean sea level and doesn’t account for gravity variations.
Currently, the accepted method is to measure a mountain’s height above mean sea level, which gives Everest the title of tallest, despite other mountains having strong claims. To summarize, it’s relatively easy to determine where a mountain ends, but there’s less consensus on where it starts. So, when it comes to identifying the tallest mountain, we might first need to clarify that starting point.
Stay curious!
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This version removes informal language, jokes, and any potentially inappropriate content while maintaining the educational essence of the transcript.
Mountains – Large landforms that rise prominently above their surroundings, usually having steep slopes and a significant height difference compared to the surrounding terrain. – The Himalayas are a famous range of mountains that include some of the highest peaks in the world.
Height – The measurement of how tall something is from its base to its top. – The height of Mount Everest makes it the tallest mountain on Earth.
Crust – The outermost layer of the Earth, composed of rock, which forms the continents and ocean floors. – The Earth’s crust is divided into several large and small tectonic plates.
Tectonic – Relating to the structure and movement of the Earth’s crust, which can cause earthquakes and form mountains. – Tectonic activity is responsible for the formation of the Andes mountain range.
Erosion – The process by which natural forces like water, wind, and ice wear away rocks and soil. – Erosion by rivers can create deep valleys and canyons over time.
Measuring – The process of determining the size, length, or amount of something, typically using instruments or tools. – Scientists are measuring the rate at which glaciers are melting due to climate change.
Technology – The application of scientific knowledge for practical purposes, especially in industry and research. – Advances in satellite technology have improved our ability to monitor weather patterns and natural disasters.
Sea – A large body of saltwater that is smaller than an ocean and is partially enclosed by land. – The Mediterranean Sea is known for its unique biodiversity and historical significance.
Plates – Large, rigid pieces of the Earth’s crust that move and interact with each other on the planet’s surface. – The movement of tectonic plates can cause earthquakes and volcanic eruptions.
Everest – The highest mountain in the world, located in the Himalayas on the border between Nepal and China. – Climbing Mount Everest is considered one of the greatest challenges for mountaineers.
