10 Earth Facts You Didn't Know

 the earth isn't just the third rock from  the sun it's our home  but it's much more than that it's home  to all the life in the universe that we  know about so far  in spite of this mind-boggling fact  we've still treat our blue planet poorly  sometimes in order to appreciate  something you need to be reminded of why  it's so special in the first place  welcome to  today we're  looking back at our own pale blue dot  in 10 things you didn't know about earth  10. a unique neighbor to the people of  earth  the moon just looks like well the moon  but in terms relative size it's gigantic  we're talking 27 percent the diameter of  earth  and although it's the fifth largest moon  in our solar system  there are no others even close to a  ratio of one to four  to give it some scale if you overlaid  the moon's profile on the earth's  surface  you'll be roughly the same area as the  continent of australia  and that place is huge it moves in an  elliptical orbit around the earth  moving closer to the earth and then  further away every large object in the  solar system gravitationally influences  the moon's orbit  so much so that it's gradually receding  from the earth every year it gets 1.6  inches more distant and slows the  earth's rotation by a fraction  making the day 2 milliseconds longer  every 100 years  9. make up your mind everyone knows that  penguins are only found in the southern  hemisphere  and the south pole in antarctica up at  the north pole there are none of these  feathered friends dancing to happy feet  outside of santa's workshop but would  this be the case if the polls were  reversed  every couple hundred thousand years the  magnetic field on planet earth reverses  it's absolutely a thing over the past 20  million years  the polls have flipped every 200 to 300  000 years on average  with the last one 780 000 years ago  looks like we're due should this  phenomenon occur  in the present day there would be no  doomsday event no geomagnetic cataclysm  where planes and satellites fall out of  the sky  and life on earth ceases to exist rather  boringly  the only problem human beings would have  is that navigating using a map and  compass  would become kind of useless eight  size does matter let's see a show of  hands who thinks a blue whale is the  largest creature on earth  not even close turns out the blue whale  has nothing on the humble fungus  to be precise a maria astoya  or the honey mushroom there is one  example in oregon's blue mountains that  measures 2.4  miles across covers an area of 37 acres  and is anywhere from 1 900 to 8650 years  old  that's a singular organism it does this  by linking the creamy brown caps that  grow in the sapwood of trees by  inconnected tubular structures called  rhizomorphs  these extend underground seeking more  food before colonizing a new tree  forming a vast network called myceria  7. mars on earth the most inhospitable  place on earth award has to go to the  den and kill  depression in ethiopia it's the boundary  between the active somali and nubian  tectonic plates  and closely resembles the ancient  martian surface  it's one of the lowest places on earth  more than 450 feet below sea level  the groundwater is superheated by molten  magma and erupts in showers of steam  the hot springs are discolored a sickly  yellow from the sulfur  emit chlorine gas and are extremely  acidic and toxic  it's also one of the hottest places on  earth with regular temperatures of 113  fahrenheit  topping out at 131 fahrenheit and an  annual rainfall of 4 to 8  inches it was thought the region was  devoid of life  until scientists discovered microbial  life extremophiles  whose cells lack a nucleus and have dna  randomly floating around their liquid  centers  tolerating condition unfit for other  forms of life 6.  sparkle sparkle chihuahua mexico isn't  just famous for producing the taco bell  dog  there's a place there called the cave of  crystals  home to the largest naturally formed  crystals in the world that extends  thousands of feet  below the ground calcium sulfide  dihydrate  or gypsum is mined and used as a  fertilizer  but here it is crisscrosses the cave  thicker than a man  and over 30 feet long forming beams wide  enough to use as a walkway  the sweltering hot cave has contributed  to over half a million years of  interrupted mineral growth  it was only discovered in the year 2000  when silver miners accidentally punched  through a wall  of the immense hollow cavern and thought  they had unearthed  superman's fortress of solitude 5.  subterranean sun believe it or not there  is a section of the earth's core that is  hotter than you think  imagine the earth as a peach with a skin  mushy later and a solid seed at the  center  the core consists of an extremely hot  incredibly dense solid ball  consisting of 85 iron and 15  nickel the same ratio as ferrous  meteorites  it's surrounded by an outer core layer  of liquid metal  on top of that is the mantle a layer of  silicate molten rock  otherwise known as magma covering that  is the earth's rocky crust  and the space humans occupy the churning  metal of the outer core maintains the  earth's magnetic field  but its boundary between the liquid and  solid metal cores  where the temperature is greatest at the  bullen discontinuity  it gets hot as 10 800 fahrenheit  a whole 800 fahrenheit hotter than the  surface of the sun  four big battery so we know that the  earth is really hot  but how hot well 99  of our planet is hotter than 1800  fahrenheit  and out of the remaining fraction of one  percent a whopping 99  is hotter than 210 fahrenheit the earth  gives off an incredible  40 terawatts of geothermal energy per  year  and may be the answer to how we can  harness clean renewable energy  heat is what drives the convection  currents that produce the planet's  magnetic field  and instead of letting it rise to the  surface unchecked and expelled as heat  could instead be used to turn water into  steam and drive turbines to generate  electrical power 3. a festering wound  the earth has an ozone layer surrounding  it that acts like a protective layer  preventing a huge chunk of the harmful  ultraviolet radiation  emitting by the sun from reaching the  earth  it's pretty important as without it we  see coral reefs  bleach and dye the polar ice caps start  to melt  and an exponential rise of the incidence  in skin cancer in humans  sadly a hole in this ozone barrier was  discovered in 1985  above antarctica after which the united  nations formed the montreal  protocol in 1987 banning the use of the  chlorofluorocarbons in refrigerant gas  that contributed to the hole  ozone is made up of a molecule  consisting of three  oxygen atoms and forms extremely slowly  taking up to five years to make its way  into the stratosphere  this whole isn't expected to return back  to pre-1980 levels  until the year 2065. 2.  purple people eater ancient organisms  originally used a light-sensitive  molecule called retinol  for photosynthesis and instead of  absorbing uv  absorbed green light and reflected back  red and violet light  the combination of the spectrum meant  that early life could have looked a lot  more purple than the green we know today  it's thought that chlorophyll came well  after retinol and its superior  efficiency and yield of chemical energy  made from sunlight  caused it to become the dominant  conversion method used by bacteria and  plants on earth  one pet rocks it's generally accepted  that rocks aren't alive  and you certainly can't take one for a  walk racetrack player  is an ancient lake bed in death valley  california where this  isn't strictly true as some of the rocks  that caught  home have moved as far as 820 feet  at first it was thought to be the work  of pranksters  explanations have been made that blame  everything from visitation by aliens  to shifts in the earth's magnetic field  in 2006  a nasa scientist researching weather  conditions on other planets  solved the mystery with nothing more  than a kitchen table  a plastic container and his immense  intellect  he froze a rock in water then removed it  and placed it in a tray of watery sand  by gently blowing on the rock he was  able to get it to move  under certain conditions in winter it's  possible that ice could form on the  rocks  causing them to glide across the muddy  bottom of the dried lake  as the breeze blew across them