At first glance, the Earth seems like a fairly spherical shape, but when you look closely, it’s obvious that it’s actually not perfectly round. In fact, if you were to draw an outline of the Earth on paper, it would be quite different from how we see it in photographs taken from space. This article will discuss the Earth’s non-spherical shape and why that is so.
What makes up the earth
The earth has five layers, or crusts. They are as follows from bottom to top: Lithosphere, Asthenosphere, Upper Mantle (or Lithospheric mantle), Lower Mantle and Crust. The crust of our planet is made up of different types of rocks and minerals with names like granite and sedimentary rock which form in layers due to gravity over millions of years. Each layer has its own unique characteristics that make it different from others. These layers together make up what we call the crust of our planet. This is why continents look like they have been pieced together over time. It’s because they have! A round shape: A lot of people believe that if you took all of these separate pieces and put them back together, they would create a perfectly round ball-like surface. That’s not exactly true! In fact, when all of these pieces are pieced back together you would end up with something more closely resembling an egg than anything else.
Gravity and why we do not fall off the earth
As you probably remember from high school physics, gravity causes objects to move towards each other. So why don’t we all fall off of our flat planet? It’s because of something called centripetal force, which is an outward force that acts on an object that moves in a circle. Think about when you first learn to drive; it takes some time to get used to keeping your car going in a straight line. You have to turn the wheel slightly so that your car doesn’t veer off course and crash into another vehicle or building. Centripetal force keeps us moving around in a circle (rather than flying off into space), and it’s what keeps us on our planet as well!
All about the moon
Did you know that it takes just over one month for our satellite to orbit around Earth? The moon is also much younger than most planets. Did you know that it was formed approximately 4.5 billion years ago? It is interesting to note that it wasn’t until humans first visited another celestial body in 1969 that we finally were able to see what our planet looked like from afar, providing us with photographic evidence of its (very slight!) rotundity. This realization—that we aren’t alone and that there are so many other incredible things out there in space—inspired some incredible quotes by astronauts. Neil Armstrong said, It suddenly struck me that that tiny pebble [the Moon] was the Earth . . . I put up my thumb and shut one eye, and my thumb blotted out the planet Earth. I didn’t feel like a giant.
How tides influence our planet
The moon’s gravitational pull is what makes tides happen on Earth, but it also affects our planet’s shape. Tides are caused by gravity from both the sun and moon, which is why we see two high tides every 24 hours—one due to each celestial body pulling in opposite directions. Since those bodies aren’t perfectly symmetrical (for example, our moon isn’t perfectly round), their influences aren’t uniform across our planet. This means that some parts of Earth experience stronger tidal forces than others; these areas bulge out slightly as a result. This uneven distribution of mass creates friction between our planet’s surface and its core, causing it to deform into an oblate spheroid rather than a perfect sphere. In other words, if you were standing at sea level at one end of our world, you would experience higher or lower tides depending on where you were standing.
Importance of Plate Tectonics
For more than a century, geologists have known that continental drift—the slow, grinding movement of tectonic plates—causes landmasses to gradually shift position. But it wasn’t until scientists were able to model how two moving continents would interact with one another (and how oceanic ridges between them would bend as they passed by) that we could fully understand why our planet isn’t flat. Without plate tectonics, there wouldn’t be any mountains or valleys; without mountains and valleys, there wouldn’t be any earthquakes or volcanoes; without these geological features, life on Earth wouldn’t exist. (Well, not in its current form.) In short, you can thank plate tectonics for pretty much everything about your day-to-day existence. So next time you take a trip to Grandma’s house for Thanksgiving dinner, remember to say thanks to Mother Nature!
Where does gravity come from
According to Newton’s law of universal gravitation, all objects with mass attract one another. The strength of gravitational attraction depends on both masses and distance between them, and gravity’s effect becomes stronger as objects get closer to one another. Gravity is responsible for keeping our planet from hurtling out of orbit—as well as keeping us grounded. In fact, gravity keeps most everything in orbit; including suns around their own planets, stars around galaxies and even galaxies themselves around superclusters. Without it, we’d be floating aimlessly through space. You know, like that scene at the end of 2001: A Space Odyssey. (In case you didn’t watch that movie.) Despite being able to explain why things fall down, Newton couldn’t say what kept things from falling up instead. As far as he knew, there was no force pulling on anything above Earth’s surface. That changed when Einstein came along. In his theory of general relativity, he showed that gravity isn’t just a force but rather an interaction between matter and energy.
The importance of water on our planet
Water is critical to life as we know it. In order for our planet to be hospitable to organisms such as humans, it has to have an atmosphere that’s made mostly of nitrogen and oxygen and a surface water supply. Without these two compounds, Earth would be uninhabitable by most species that inhabit its surface today. But how did these key ingredients come about? Scientists aren’t exactly sure. However, there are a few hypotheses regarding what happened when our planet was first formed billions of years ago. Let’s take a look at them below.
One hypothesis suggests that all water on earth was delivered by icy comets. During formation, our planet may have been bombarded with large chunks of ice coming from space. If true, nearly all of Earth’s water could have been deposited via cometary impacts – which makes sense considering more than half of our current oceans are salty (implying they came from melted ice). Another theory suggests that volcanoes brought us water in gaseous form millions or even billions of years ago.
