Can You Pass This Basic Science Of Planet Earth Quiz?


By: John Miller

6 Min Quiz

Image: Yuichiro Chino/Moment/Getty Images

About This Quiz

Like an exceptional lifeboat drifting through the universe, our Earth is a strange and wonderful place. From its majestic Himalayan mountains to the black fathoms of the Mariana Trench, from the gurgling geysers of Yellowstone to the empty cold heart of Antarctica, it’s full of odd and captivating places. Each varying ecosystem is driven by many of the same geologic forces and weather principles that affect every corner of the planet. But what do you really know about the basis facts of Earth science?

The planet’s composition alone is very different from others in the Milky Way galaxy and even in our own solar system. The fundamental building blocks of the Blue Planet affect everything from our atmosphere, to the amount of solar radiation we experience, and the makeup of the very air we breathe. Change just a bit of this formula and, suddenly, our safe haven in the stars would be very inhospitable. What do you recall about the environmental conditions that result from our planet’s various cycles?

The Earth is not an unchanging mass of rock. Driven by heat, friction, gravity, erosion and the interplay of countless other dynamic factors, the planet is virtually a lifeform unto itself. Wade into the salty waters of this amazing Earth science quiz now!

Compared to other planets in the solar system, how close is Earth to the sun?

Earth is the "third rock from the sun." And we don't really want to be any closer, because if we were, we'd fry.


About 70% of Earth is covered by what?

Water, glorious water, covers the vast majority of Earth's surface. And the bulk of that water is salty, meaning we can't drink it without processing plants.


Earth is the only planet in our solar system known as home to what?

So far as we know, Earth is the only planet in the solar system -- and the entire universe -- to contain life. But many scientists believe it's only a matter of time before we find life on other planets.


Where is the driest place on Earth?

Chile's Atacama Desert is an extreme place, the driest area on Earth. In some areas of this region, humans have never once recorded precipitation of any kind.


Most of Earth is made up of what?

We'll never run out of iron on Earth. That element makes up about 32% of the planet. The vast majority of that iron is very deep, near the Earth's center.


If you drilled straight down, what would you find under the North Pole?

There is no solid ground under the North Pole. There's nothing there but sea ice floating on water, a dark and mysterious place untouched by sunlight.


Oceans cover about 70% of Earth's surface. How deep (maximum) are those waters?

The oceans are incredibly vast. Not only do they cover 70% of the planet, but they're deep -- at least 2.5 miles deep.


What's the hottest temperature ever recorded on Earth's surface?

In 1922, a weather station in El Azizia, Libya, recorded the hottest temperature ever. It was 136 degrees Fahrenheit. But hey, it was dry heat.


Where would you find the thinnest layer of Earth's crust?

Because the oceans are so deep, they logically take up much of the space that would otherwise be consumed by crust. That's where you find the crust at thinnest, in some places only three miles thick.


Where do 90% of earthquakes occur?

The Pacific Ocean is home to the infamous Ring of Fire, an area of incredible tectonic and volcanic activity. Roughly 90% of the world's earthquakes happen in this sprawling area.


Near Earth's surface, the air is mostly made up of what?

You might think that oxygen is the most prevalent gas near the ground. But it's actually nitrogen that makes up nearly 80% of air near terra firma.


What layer would you find just below the Earth's crust?

The crust is the outermost layer of the Earth's composition. Just below the crust is the mantle, and below that, the outer core.


What's the deepest hole that humans have ever drilled into the Earth?

In 1970, the USSR started drilling to see how far it could get into the Earth's surface. After 20 years the Kola Superdeep Borehole was complete … and it went 7.5 miles down.


Yellowstone National Park is, at its most fundamental level, what?

Yellowstone is vast wilderness. It's also a bubbling cauldron. It's a massive volcano, and one that could eventually erupt again.


What makes up the inner core of the Earth?

The very inner core of the Earth is solid, not molten lava or gooey caramel goodness. It is mostly iron-nickel alloy, a material that makes up many planetary cores.


Where would you find the world's biggest supply of surface freshwater?

America's Great Lakes are truly great, a massive repository of freshwater. They contain about 20% of Earth's surface freshwater and have a surface area of more than 95,000 square miles.


What shape is the Earth?

Our Earth is not a perfect sphere. Instead, it's a slightly flattened sphere -- the exact term is oblate spheroid, and we promise that's not actually a scary medical term.


What's one major reason that Earth has plentiful oxygen?

Plants suck in a lot of carbon dioxide and expel oxygen. That oxygen is exactly what humans and countless other creature need for survival.


Where would you find the bulk of Earth's freshwater?

Much of it is frozen in time and place … in Antarctica. That's where about 70% of our planet's freshwater is located, suspended in ice.


Earth is very, very old. About how old is our planet?

The Big Bang started it all. And as celestial bodies began to collide and form in the aftermath, Earth formed, too -- about 4.5 billion years ago.


How far does Earth's atmosphere extend into space?

Earth's atmosphere is densest within the first few miles. But that atmosphere extends for an incredible distance -- 10,000 km, or more than 6,200 miles.


Earth's atmosphere protects humans from which threat?

Our universe is cluttered with countless meteoroids (most the size of pebbles) zipping around to and fro. The vast majority of those meteoroids burn up and fragment into harmless pieces thanks to our protective atmosphere.


Where did the world's most powerful (recorded) earthquake happen?

In 1960, scientists recorded the most powerful earthquake ever. It's called the "Great Chilean Earthquake," and it had an incredible magnitude of 9.5.


Iron has some crazy properties. Earth's iron core causes what?

The molten outer core of Earth's depths is made of iron. And that iron helps to generate a magnetic field around Earth … and that field keeps much of the sun's radiation from striking the planet's surface.


The Earth is just one of several planets in the solar system. How far is it from the sun?

Would you like to go on a one-way vacation to the glorious ball of fire in the sky? Good luck -- it's 93 million miles away.


Tectonic plates are massive moving puzzle pieces of the Earth's crust. The Earth's crust is generally regarded as having how many major tectonic plates?

Scientists generally agreed that there are seven major tectonic plates. As these plates slowly collide they create mountains; as they drift away, valleys and oceans form.


At the equator, the surface of the Earth spins at about what speed?

Earth's rotational spin is (thankfully) imperceptible to us as we stand on the surface. Near the equator, the planet's spin is speediest, at around 1,000 MPH.


What's special about Australia's tectonic plate?

Most of Earth's tectonic plates are tortoises … Australia's is a jackrabbit. It moves so fast that engineers and mapmakers have to account for its high speed. Since 1994 alone, the plate has drifted more than five feet.


About one-third of Earth's freshwater is located where?

A huge portion -- about a third -- of Earth's freshwater is underground. Major stores of freshwater are called aquifers.


How many rings circle the Earth?

Saturn, that greedy ring-grabber, got all of the rings. Earth has no rings, not even faint ones.


What happens when Earth's mantle breaks through the upper crust?

In most places, the crust forms a solid layer. But in a few areas, like the Pacific's Ring of Fire, the mantle pushes through … and that's where volcanic eruptions occur.


How fast do Earth's tectonic plates move?

Slow but steady is the key for tectonic plates. These gigantic features of Earth's crust move about as fast (or slow) as your fingernails grow.


What's one stunning visual consequence of Earth's magnetic field?

The northern and southern lights -- the aurorae -- are a result of Earth's magnetic field. They appear when solar winds smash into air near our planet's magnetic poles.


How does the inner core spin relative to the rest of Earth?

The inner core, resting in the molten outer core, spins at a different speed than the rest of the planet. Scientists think this what causes our planet's magnetic field.


Which of the following elements is most common in Earth's crust?

By weight, oxygen makes up nearly half of Earth's crust. But don’t go trying to inhale your garden soil anytime soon, as that oxygen is intermingled with all sorts of other materials.


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