Categories
Planet Earth Animals Astronomy Evolution Life on Earth Prehistoric Solar System

Top 10 Misconceptions about Earth

Our home planet is a complex and wondrous place, brimming with mysteries and surprises. Yet, in the vast expanse of knowledge we hold about Earth, some misconceptions have taken root. These widely held but incorrect beliefs often stem from outdated textbooks, misunderstood science, or the oversimplification of complex concepts for ease of learning. They range from ideas about the shape of the Earth and the causes of the seasons to beliefs about the composition of the atmosphere and the workings of Earth’s ecosystems.

Dispelling these misconceptions is not just about correcting facts; it’s about deepening our understanding of the world around us and fostering a more informed appreciation of our place within it. Here are the top ten misconceptions about Earth.

Common misconceptions about Earth

1. The Great Wall of China is visible from space

Reality: One of the common misconceptions about Earth, the Great Wall of China is frequently billed as the only man-made object visible from space, but most times, it isn’t. In fact, according to NASA, it is very difficult to see or photograph the Great Wall from low Earth orbit. It very rarely can be visible in the low orbit, and to an aided eye, under special conditions. (Source: NASA)

But, you can see a lot of things people have made, and perhaps most visible from low Earth orbit are cities at night. Cities can be seen during the day too, as can major roadways and bridges, airports, dams, and reservoirs. (Source: NASA)

On 21 June 2018, ESA Astronaut Alexander Gerst wrote “I think I finally found the answer to a question I’ve been asked a 1000 times. ‘Can we see the Great Wall of China from the #ISS?’ Next to impossible with the naked eye. But I tried with an 800 mm telelens. Still tough to spot”.

Common misconceptions about Earth: Contrary to popular belief, The Great Wall of China is very rarely visible from space
Common misconceptions about Earth: Contrary to popular belief, The Great Wall of China is very rarely visible in the Low Earth Orbit (LEO), and to an aided eye, under special conditions. It’s impossible to see it in the Medium Earth Orbit (MEO) and beyond. Image source: Deposit Photos

2. In the summer, the Earth is closer to the Sun, and in the winter vice versa

Reality: A very common misconception about Earth. If it were true, how can we explain the fact that when it’s winter in the northern hemisphere, it’s summer in the southern hemisphere? No, the seasons exist because Earth’s axis is today tilted 23.5 degrees from the plane of its orbit around the Sun. But this tilt changes. During a cycle that averages about 40,000 years, the tilt of the axis varies between 22.1 and 24.5 degrees. Because this tilt changes, the seasons as we know them can become exaggerated. More tilt means more severe seasons – warmer summers and colder winters; less tilt means less severe seasons – cooler summers and milder winters. (Source: NASA)

How does Earth’s tilt create seasons?

Earth's tilt creates seasons
Common misconceptions about Earth: Seasons do not occur because of the distance of Earth from the Sun. Earth’s tilt creates seasons. During winter in the northern hemisphere, the Earth is tilted so that the Southern Hemisphere receives more sunlight. During summer in the Northern Hemisphere, the Northern Hemisphere gets more sunlight.

Earth’s tilt is the angle between its rotational axis and its orbital plane around the Sun, which is approximately 23.5 degrees. This tilt is responsible for the changing seasons as Earth orbits the Sun.

During its yearly orbit, different parts of Earth receive varying amounts of sunlight. When the Northern Hemisphere is tilted toward the Sun, it receives more direct sunlight and experiences warmer temperatures, which we call summer. At the same time, the Southern Hemisphere is tilted away and receives less direct sunlight, leading to cooler temperatures and winter there.

Conversely, when the Southern Hemisphere tilts toward the Sun, it has summer, while the Northern Hemisphere has winter. The tilt ensures that at different times of the year, the Sun’s rays hit different parts of Earth more directly.

The two points in Earth’s orbit where neither hemisphere is tilted toward or away from the Sun are called the equinoxes. During an equinox, both hemispheres receive approximately equal amounts of sunlight, and this results in the transition seasons of spring and autumn.

The most extreme tilts are during the solstices. The summer solstice is when one hemisphere is tilted most directly toward the Sun and has the longest day and shortest night of the year. The winter solstice is the opposite, with the hemisphere tilted away from the Sun, experiencing the shortest day and longest night.

Without Earth’s tilt, we would not have seasons as we know them. There would be minor temperature variations due to Earth’s slightly elliptical orbit, but the global distribution of sunlight would be more constant throughout the year, leading to a more uniform climate across the planet.

Earth’s orbit is not strongly elliptical

Most people think the Earth’s orbit is (and in general, all the planets’ orbits are) strongly elliptical (another misconception that is the source of this one). No, the Earth’s orbit is (and in general, planets’ orbits are) very close to a circle. This misconception is due to orbits being shown from an oblique view in most textbooks (and also in the image above, showing how Earth’s tilt creates seasons) to save space.

Earth orbit - Perihelion and Aphelion
Earth’s Orbit: Perihelion and Aphelion – The closest and farthest points in Earth’s orbit around the Sun. During perihelion, Earth reaches its closest approach to the Sun. It occurs every year around January 4. Conversely, during aphelion, Earth is farthest from the Sun, which occurs every year around July 5.

Earth’s distance from the Sun (center-to-center) varies with mean values of 0.9832899 AU (147,098,074 km or 91,402,505 miles) at perihelion (closest) to 1.0167103 AU (152,097,701 km or 94,509,129 miles) at aphelion (most distant).

While that is a difference of over 3 million miles, relative to the entire distance, it isn’t much.

Aphelion (when Earth is farthest from the Sun) occurs in July, and perihelion (when we are closest) occurs in January. For those of us who live in the Northern Hemisphere where it’s summer in July and winter in January, that seems counterintuitive, doesn’t it? That just goes to prove that Earth’s distance from the Sun is not the cause of the seasons.

Source: NASA

3. Dinosaurs are extinct

Reality: Yes, most of them are extinct. But not the avian dinosaurs. Birds (Aves), also known as avian dinosaurs are still well and alive.

The Cretaceous-Paleogene (K–Pg) extinction event, also known as the Cretaceous-Tertiary (K–T) extinction which occurred approximately 66 million years ago caused the extinction of all dinosaurs except for the line that had already given rise to the first birds.

Based on the features of the skeleton, most people studying dinosaurs consider birds to be dinosaurs. This shocking realization makes even the smallest hummingbird a legitimate dinosaur. So rather than refer to “dinosaurs” and birds as discrete, separate groups, it is best to refer to the traditional, extinct animals as “non-avian dinosaurs” and birds as, well, birds, or “avian dinosaurs.” (Source: Berkeley.edu)

Common misconceptions about Earth: Great bustard
Common misconceptions about Earth: Dinosaurs didn’t go extinct. Birds are “avian dinosaurs”. Source: Deposit Photos

Birds are considered avian dinosaurs because they directly descend from the theropods, a group of dinosaurs that includes the mighty Tyrannosaurus rex and the smaller, feathered Velociraptors. This evolutionary lineage means that birds are not merely related to dinosaurs; they are actually classified as one and the same, specifically as a subgroup within the theropod dinosaurs.

The transition from non-avian dinosaurs to avian species (birds) is well-documented by a wealth of fossil evidence. Paleontologists have found many transitional fossils that showcase characteristics common to both birds and non-avian dinosaurs, such as feathers, similar bone structures, and other shared anatomical features. Key examples include Archaeopteryx, which exhibits both avian features like wings and feathers and dinosaurian traits like teeth and a long bony tail.

Furthermore, many traits once thought unique to birds, like feathers and brooding behaviors, have been discovered in fossilized forms in non-avian theropods, demonstrating that birds inherited and retained these traits from their dinosaur ancestors. Modern birds are, therefore, not only descended from dinosaurs but are dinosaurs themselves, the only lineage of the dinosaur clade to survive the mass extinction event 66 million years ago.

4. South of the Equator toilets flush and tornadoes spin in the opposite direction

Reality: No, they don’t.

The widespread belief that the Coriolis effect causes water to drain and air to circulate in opposite directions in different hemispheres is a misconception, particularly when applied to small-scale systems. The Coriolis effect is indeed a real force that emerges from Earth’s rotation and it does influence the movement of large atmospheric and oceanic phenomena. For example, it contributes to the clockwise rotation of storm systems in the Southern Hemisphere and counterclockwise in the Northern Hemisphere.

However, the Coriolis effect is too slight to affect the direction of water draining from a sink or bathtub, or the small-scale circulation of air in a room. These small systems are overwhelmingly influenced by other factors such as the shape of the basin, the initial motion of the water or air, and other local conditions. The initial conditions and the design of the system will have a far greater impact on the rotation direction than the Coriolis effect.

In the case of large weather systems like hurricanes and cyclones, which extend over thousands of kilometers and last for days, the Coriolis effect has a significant influence on their rotation direction. But for everyday phenomena like water going down a drain, it’s all about the immediate physical circumstances, not the hemisphere you’re in.

The persistence of the myth likely stems from a misunderstanding of how the Coriolis effect operates on different scales. For a clear and authoritative exploration of the Coriolis effect, resources such as meteorology textbooks, the American Meteorological Society, or educational websites of major research institutions would provide accurate information.

Common misconceptions about Earth: Water draining in sink
Common misconceptions about Earth: Contrary to myth, the swirl of water draining in this sink isn’t dictated by its location in the Southern or Northern Hemisphere. Instead, the direction is influenced by the sink’s design and the water’s initial movement. The Coriolis effect, while crucial in steering large-scale atmospheric patterns, is imperceptible in such small-scale situations. Image source: Deposit Photos

5. Large earthquakes increasing in frequency

Reality: Scientists have analyzed the historical record and found that the increase in seismic activity was likely due to mere chance. Peter Shearer at Scripps Institution of Oceanography and Philip Stark at the University of California, Berkeley examined the global frequency of large magnitude earthquakes from 1900 to 2011.

They discovered that while the frequency of magnitude 8.0 and higher earthquakes has been slightly elevated since 2004 – at a rate of about 1.2 to 1.4 earthquakes per year – the increased rate was not statistically different from what one might expect to see from random chance. The results of the study were published on January 17, 2012, in Proceedings of the National Academy of Sciences. (Source: EarthSky.org)

6. Deserts are always hot

Reality: The driest desert on Earth is in Antarctica: McMurdo Dry Valleys. The Friis Hills in Taylor Valley, one of the McMurdo Dry Valleys haven’t seen water in 14 million years. (Source)

Deserts are also not rare, and not always sand-covered areas – other common misconceptions. About one-third of the land surface of the world is arid or semi-arid. This includes much of the polar regions where little precipitation occurs and which are sometimes called polar deserts or “cold deserts“.

Also, the Largest Desert is not the Sahara: The Sahara is the largest hot desert, but the largest desert overall is Antarctica, which is classified as a cold desert.

Wright Valley, McMurdo Dry Valleys, Antarctica - from the Bull Pass
Common misconceptions about Earth: Wright Valley, McMurdo Dry Valleys, Antarctica – from the Bull Pass. McMurdo Dry Valleys is the driest place on Earth. Also, Antarctica is the largest desert in the world. Photo by David Saul – Own work, Public Domain, Link

7. The needle of the compass points to the true north

Reality: it points to the magnetic north or the North Magnetic Pole which moves over time due to magnetic changes in the Earth’s core. In 2001, it was determined by the Geological Survey of Canada to lie near Ellesmere Island in northern Canada at 81.3°N 110.8°W.

The north magnetic pole was situated at 83.1°N 117.8°W in 2005. In 2009, while still situated within the Canadian Arctic territorial claim at 84.9°N 131.0°W, it was moving toward Russia at between 55 and 60 kilometers (34 and 37 mi) per year.

In 2016, it was located at approximately 80°22′12”N 72°37′12”W, over Ellesmere Island, Canada but it is now drifting away from North America and toward Siberia. (source: Wikipedia)

The discrepancy between true north and magnetic north is known as magnetic declination, which varies depending on where you are on Earth. For accurate navigation, compass users must adjust for this declination to find the true north. Without adjustment, they would follow a magnetic azimuth, which could lead them astray from their intended geographic path.

Common misconceptions about Earth: The needle of the compass points to the true north
Common misconceptions about Earth: The needle of the compass points to the true north. Image source: Deposit Photos

8. A large portion of the Earth’s oxygen is produced by the Amazon rainforest

The Amazon rainforest, often described as the “lungs of the Earth,” is believed by many to be the principal producer of the planet’s oxygen. This vast expanse of greenery does play a crucial role in Earth’s oxygen cycle, but the reality of its contribution to the world’s oxygen supply is more nuanced than it might seem.

While the Amazon does produce a large amount of oxygen through photosynthesis, it consumes the majority of it through respiration and decomposition processes within the ecosystem. The lush flora of the rainforest takes in carbon dioxide and sunlight to make food and grow, releasing oxygen in the process. However, this oxygen is almost entirely used by the forest itself and by the organisms that decompose dead plant matter. What’s more, when trees die and decompose, or when they are burned, they release the carbon they have stored back into the atmosphere, sometimes as carbon dioxide, which can negate the oxygen-producing effects.

In reality, the majority of Earth’s oxygen doesn’t come from terrestrial forests but from the oceans. Tiny marine organisms known as phytoplankton contribute at least 50% of the planet’s oxygen. These microscopic plants drift through the sunlit upper layers of the ocean and perform photosynthesis on a massive scale. They are the true unsung heroes of our global oxygen supply, highlighting the crucial role of the oceans in Earth’s ecological balance and the importance of protecting marine life.

9. If the Earth were slightly closer/farther from the Sun, it would be uninhabitable

Reality: This misconception about Earth is widely popular among creationists. They spread the myth that Earth’s habitability is critically dependent on a precise distance from the Sun to support the idea that the planet was perfectly designed for life. This argument is often used to counter scientific explanations about the vastness of the universe and the potential for numerous habitable planets. By emphasizing the supposed fine-tuning of Earth’s position, creationists aim to argue for intelligent design over natural processes like planetary formation and evolution.

However, this perspective dismisses not only the adaptability of life but also ignores the fact that Earth’s orbit is elliptical, varying by about 3 million miles (about 5 million kilometers) over a year, which under scientific scrutiny, does not significantly affect our planet’s ability to support life.

Common misconceptions about Earth: Sunset
Common misconceptions about Earth: “If the Earth were slightly closer/farther from the Sun, it would be uninhabitable” – No, Earth’s habitability is more resilient to its orbital distance than this misconception implies. The habitable zone is quite wide, and Earth’s climate is regulated by a complex interplay of atmospheric conditions, not just distance from the Sun. Image: “Beautiful, colorful sky and sunset at the sea” on Deposit Photos

The habitable zone, sometimes referred to as the “Goldilocks zone,” is the region around a star where conditions might be right for liquid water to exist on a planet’s surface – a key ingredient for life as we know it. This zone is actually quite broad. For our solar system, it stretches roughly from beyond the orbit of Venus to the orbit of Mars. Within this range, a planet’s atmosphere and geological activity play significant roles in maintaining a stable climate.

Earth’s climate is also heavily influenced by its atmosphere, which acts like a blanket to retain heat through the greenhouse effect. Variations in atmospheric composition can have a large impact on the climate. For instance, Venus has a runaway greenhouse effect that keeps it extremely hot, even though it is only slightly closer to the Sun than Earth. Mars, being further away and having a thin atmosphere, is much colder.

Moreover, life on Earth has adapted to a wide range of climatic conditions and can survive in both hotter and colder environments than those typically experienced in moderate latitudes. This adaptation capacity suggests that slight changes in Earth’s orbit alone would not automatically make the planet uninhabitable. Major changes could certainly challenge the current forms of life and lead to significant shifts in ecosystems and climate, but these changes would need to be quite substantial to render the planet completely lifeless.

10. There is a dark side of the Moon

Reality: The Moon has no side that is constantly dark; the front and back are alternately lit as the Moon rotates. “Far-side” is a more accurate term. (Source: NASA)

The term “dark side of the Moon” incorrectly implies that one side of the Moon is perpetually dark. In reality, all parts of the Moon experience day and night just like Earth. This misconception arises because the Moon is tidally locked with Earth, meaning the same side of the Moon always faces Earth due to the synchrony between its rotation around its own axis and its orbit around Earth.

The side we never see from Earth is more accurately called the “far side” of the Moon. Both the near side (the side facing Earth) and the far side experience two weeks of sunlight followed by two weeks of night. The far side was completely unknown to humans until the Soviet Luna 3 spacecraft sent back images in 1959.

Bonus misconception: The Earth is as smooth as a billiard ball

No, it’s not. Here’s why the earth is NOT as smooth as a billiard ball.

Is Earth as smooth as a billiard ball?
Common misconceptions about Earth: Is Earth as smooth as a billiard ball? No, it’s not
M. Özgür Nevres
Özgür Nevres

By M. Özgür Nevres

I am a software developer and a science enthusiast. I was graduated from the Istanbul Technical University (ITU), Computer Engineering. In the past, I worked at the Istanbul Technical University Science Center as a science instructor. I write about the planet Earth and science on this website, ourplnt.com. I am also an animal lover! I take care of stray cats & dogs. This website's all income goes directly to our furry friends. Please consider supporting me on Patreon, so I can help more animals!

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.