It ’s probably best if we do n’t think too much about Earth . After all , it ’s a tiny globe spinning more than 1000 miles per hour at the equator while simultaneously zipping throughspaceat 67,000 mph . It circles a mysterious , 10,000 ° Fsunthat ’s more than 100 multiplication its size , and spends most of its range narrowly ( in a cosmic sense ) avoiding collisions with giant chunk of rock that could much wipe its Earth’s surface fair . But if you ’re feel brave , here are a few things you might not bonk about Earth .
In 2017 , Mental Floss spoke toJosh Willis , a clime scientist atNASA ’s Jet Propulsion Laboratory , about the satellite we call home .
1. Earth is about 93 million miles away from the sun.
As you credibly know , at this distance , it take one year for Earth to complete one revolution of its orbit , and 24 hour to fill out one rotation on its axis . The surface of Earth has temperatures ranging from -126 ° F to 136 ° atomic number 9 . The planet is about 7900 miles in diameter ( though thedeepest we ’ve ever drilledis 7.6 mile ) . There are roughly332.5 three-dimensional miles of wateron the planet , which is enough that , if the water broke off from Earth and organized itself into a sphere , it would have a diameter of860 miles — about 40 per centum that of themoon .
2. The first photograph of Earth from space was taken in 1946.
It ’s a grainy , pitch-black - and - white-hot shot of a tiny slice of our world , curve with the ink of space as a backdrop . In 1960 , weather satellites began commit photographs back to Earth , look-alike that were still monstrously deformed but scientifically valuable , especially for meteorologist , who now hadstunning persuasion of cloud systemsfrom which to work . NASA ’s ATS - III orbiter in 1967 returned the first coloring images of Earth in its entirety . At last , we could see our living humanity , ringed in space and wrap in surge clouds .
On Christmas Eve , 1968 , Apollo 8 astronaut William Anders send backEarthrise , a now - iconic photograph of a tenuous sapphire orb rising over the lunar open . But the most famous photograph of the Earth , by far , was taken about four years later , on December 7 , 1972 : theBlue Marble . You ’ve probably seen it countless times , but you may be less familiar with how astronaut Harrison Schmitt account the sight to Mission Control : “ I ’ll recite you , if there ever was a delicate - appearing slice of blue in space , it ’s the Earth mightily now . ”
3. Earth has a natural satellite.
worldly concern is the first major planet , move outwards from the sunlight , that possess a moon . We call our Sun Myung Moon “ the moon ” ( which will be a real head ache C from now , when we ’ve colonized the solar system ) . Every 27.32 day , the lunar month completes an orbit of Earth , which is why it has phases . When Earth is between the sunshine and the moon , we see the moon in full clarification ( a round orb ) . As it circles Earth , less and less of its seeable surface is sort out , until at last the moon is between the Sunday and Earth . At that power point , the “ far side ” of the synodic month is in full illumination , and from our view , the moonshine is get no light at all . The hertz then double itself , with more of its disk being illuminated as the month elapses , until it is again full . Because the duration of the lunar month ’s orbital cavity is just diffident of a month , every so often a month ( which gain from the wordmoon ) has two full moons , the second of which is forebode a blue lunation .
The lunar month does spin , but in synchronal rotation with Earth . In other words , it spin at the same speed as its range . As a outcome , Earth gets to see only one side of our only rude satellite . The best guess forthe source of the mooninvolves an object the size of Mars smashing into Earth 4.5 billion years ago , sending debris into place . This debris organized itself into a molten form of the Mexican onyx orb we know and love . Within 100 million year , an early crust had set out to form . Today , the moon mold the tides of the sea and allay our axial wobble , keeping thing ( more or less ) nice and unchanging — a staring condition for life .
4. Earth is the only body in the universe known to harbor life.
When it comes to spirit , there are a lot of maybes in the solar system . MaybeMarssupported life-time billions of geezerhood ago . MaybeJupiter ’s moon Europais stream with life today . The problem is that there is noevidenceanywhere of anything that wiggles , walks , or swims … except on Earth . And it has been tough going .
Four billion years ago , Earth ’s airfoil was desex during theLate Heavy Bombardment , when asteroids pummeled the inner solar system . To get some idea of what thing must have been like during the LHB , look at the moon . Most of its volcanic crater were organize during that time . Life survived on Earth in large part thanks to thehydrothermal ventsat the bottom of the ocean .
There have been five mass extinctions on Earth , the spoilt of which ( thePermian - Triassic , or “ P - T Event ” ) was 250 million years ago , wiping out 96 percent of marine metal money and nearly three - twenty-five percent of land vertebrate . Sixty - six million long time ago , theChicxulub impactwiped out75 percent of all lifeand ended the reign of the dinosaur . Things recovered nicely , though , and today , biologists think there could be8.7 million speciesof liveliness on Earth . That ’s not bad considering the universe ’s apparent antagonism to biography , and make what we have go here all the more extra and worth preserving . And we ’d better get on it : Many scientists argue that we ’re in the thick of asixth mess extermination — and we can only partiallyblame it on Caterpillar .
5. Climate change is threatening life on Earth.
“ Global thawing is real , it ’s because of the great unwashed , and it ’s a big problem , ” Willis tell Mental Floss in 2017 . “ Every year the impacts of homo - make clime modification get bigger and bigger , and are felt more and more across the planet . ” We sense the force of climate change today , but the worst is yet to issue forth in damage of economical and social disruption : “ Right now we have a choice about what sort of major planet we want to have in the hereafter . And the choice is : Do we need to continue to burn fossil fuels and heat up Earth , or do we want to try and stabilize our mood and keep it more or less like we ’ve had it for the last 10,000 eld ? ”
6. Earth is the only planet with stable water at its surface.
arctic moons likeEuropaandEnceladushave subsurface sea of limpid water , and Titan , in summation to a potential subsurface water sea , has vast lakes of liquid methane insure its surface — but no other heavenly object has ocean ofH2Olike ours .
Unfortunately , they ’re arise . NASA’sJason-3spacecraft measure the height of the sea with 1 - inch truth . Every 10 days , it collects data point on the intact ocean , reveal details about such thing as ocean current and how they change , tilts in the ocean ’s surface , and the modal volume of the ocean . “ The oceans are mature for two reasons , ” Willis tell . “ One is because they absorb heat entrap by the glasshouse gaseous state , and the other is that the ice in places like Greenland andAntarcticaand tiny glaciers all across the satellite are all dissolve and adding extra water to the oceans . This satellite measures these things blend , and in a path it ’s really take the beat of our planet . ”
A decade ago , the sparkler sheets in Greenland and Antarctica were thought of as stable . They are the last remaining frappe sheets that cover huge land masses , andtoday they are disappear . In 50 years , their melting will be the dominant source of global ocean grade rise . " Every time a crowing discovery is made , " read Willis , " it seems like the depiction is worse than we thought it was . The opening for really speedy methamphetamine hydrochloride red and speedy sea degree rise is keen than we cogitate . "
7. In some ways, Earth’s oceans are harder to study than other planets.
The oceans stay agiant unknownfor scientist . Knowing more about them would answer many of our interrogation about life and the life of Earth . “ Two - thirds of the major planet is covered with piddle , and you ca n’t see through it . And you ca n’t hit microwave through it , and radio waves , and all the other kinds of thing that we practice even to measure other planets , ” Willis said . “ If you examine the sea , there are still a destiny of big mysteries down there . ”
To understand how ocean really puzzle out would explain , for object lesson , where the heat energy from spherical warming is going . Though the oceans absorb 95 pct of the heat trapped by nursery gases , it ’s still a mystery where that heat energy actually goes . Similar questions survive as to how the oceans interact with ice rink sheet .
8. It isn’t too late to take action for Earth’s future.
But it will take a cooperative effort to change our behavior — before it ’s too late . “ We think ofglobal warmingas something that happens in our metropolis , and itishappening there , but really 95 pct of the heat that ’s being pin down is proceed in the oceans . And I do n’t think mass realize that . It just seems like , well , we ’re catch the brunt of global warming here in Los Angeles — but that ’s not true , really . It ’s the sea aliveness and the oceans that are getting the brunt of the change , ” Willis said .
“ One thing we should keep in mind is that all hope is not lost , ” he continued . “ We are beginning to see changes in our economy , we ’re begin to see the development of renewable energy , and the strong desire to move to a fuel rootage that does n’t cook us , and I remember that ’s a good matter . ”
A rendering of this story was published in 2017 ; it has been updated for 2023 .
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