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  • What If There Were 2 Earths in the Solar System?

  • For years we've debated a fundamental question; Are we alone in the universe?

  • And our search for extra-terrestrial life usually has scientists studying distant, Earth-like

  • planets orbiting stable stars that are lightyears away.

  • But, what if we needn't look so far?

  • This is Unveiled, and today we're answering the extraordinary question; What if there

  • were two Earths in the solar system?

  • Are you a fiend for facts?

  • Are you constantly curious?

  • Then why not subscribe to Unveiled for more clips like this one?

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  • There's actually a long-standing theory of a second Earth, orCounter-Earth,”

  • dating back to the 4th Century BC where it was first hypothesised by the Greek philosopher

  • Philolaus.

  • The theory - which was initially proposed to explain an eclipse - says that the Counter-Earth

  • is always on the other side of the sun to us, meaning that it's never visible.

  • While we eventually learnt this isn't the way planets work, the Counter-Earth has become

  • a long-standing trope of science-fiction and a belief of many conspiracy theorists, who

  • still insist it exists just beyond our reach.

  • Scientifically speaking, if there really was another Earth we'd have found it by now,

  • by studying the orbits of the other inner planets or via satellites.

  • But even though the Counter-Earth doesn't exist, there are some other ways it'd be

  • theoretically possible.

  • One idea is that it'd follow an orbit that's the exact opposite of ours, which is why it

  • would remain on the other side of the sun.

  • There are already some solar system bodies that do something similar to this, called

  • trojans.

  • These are a type of object which stay fixed in the orbit of a larger body (usually a planet),

  • but don't orbit around that body as standard moons do.

  • Jupiter and Saturn, for example, have many.

  • Another type of shared orbit is a horseshoe orbit, where an object travels part of the

  • way around a planet and then turns around and goes back in the other direction.

  • Bizarre as this may sound, there are already instances of it happening in our solar system

  • - such as the Saturnian moons, Janus and Epimetheus.

  • In fact, even Earth boasts an object orbiting in this way, a very small asteroid called

  • 2010 SO16.

  • While this still isn't a shared orbit in the way Counter-Earth theorists suggest, because

  • we know it's happening, it does provide an opportunity for another planet to exist

  • along the same path as we do.

  • However, if there was another Earth with the exact size, shape and (crucially) the same

  • orbit as ours, the results would almost certainly be catastrophic.

  • No matter how stable the two planets were, perhaps remaining equidistant for millions

  • of years, their orbits would eventually speed up until one crashed into the other.

  • Since the Earth travels at almost 19 miles per second, or 67,000 miles per hour, two

  • Earths smashing into each other would wipe out all life on each of them instantaneously.

  • A second Earth wouldn't necessarily need to share our exact orbit, though.

  • IfEarth 2” were simply another inner planet within our solar system's habitable

  • zone, then the planetary pile-up could well be avoided.

  • It's seasons would be different, perhaps its rotation speed would differ too, but it'd

  • still have the potential for life, either if we colonised it or if it developed life

  • of its own.

  • So, let's imagine that the Counter-Earth does exist in this way, and is capable of

  • maintaining its orbit without crashing into us; How different, or similar, to our own

  • planet would it be?

  • Its ability to sustain even basic life generally depends on the presence of amino acids - regarded

  • by scientists as thebuilding blocksfor life on Earth.

  • Given that there's some evidence that amino acids didn't naturally occur on Earth, but

  • instead crashed here on meteorites - couldn't the same thing happen elsewhere?

  • We can't say for sure that Earthly life only happened because of amino acid-carrying

  • meteorites, but that particular part of the puzzle really could be repeated all over.

  • So, say the second Earth does harbour the ingredients for life; What now?

  • Since humankind has yet to meet an actual extra-terrestrial, it's impossible to say

  • how that life would develop - even if we shared a star system.

  • In some ways it feels logical that any intelligent lifeform would be a mirror image of us, since

  • they'd have had to adapt to survive in almost identical conditions.

  • But there's every chance that evolution would take a totally different route, with

  • another planet to work on.

  • Instead of intelligent primates like us, the dominant species really could more closely

  • resemble reptiles, fish, birds, or something else entirely.

  • An optimistic outcome sees 'us' and 'them' communicate effectively, sharing knowledge

  • and widening perspectives without resorting to violence.

  • But, the threat of war is clear.

  • For centuries, there have been precious few moments in Earth's own history when there

  • hasn't been a war happening somewhere

  • So, the assumption that we'd immediately start fighting any aliens we meet isn't

  • that unlikely.

  • In fact, even if the second Earth housed no life of its own but was instead colonized

  • by some future space-travellers from our planetover time we'd likely see conflict arise

  • between the old and new worlds.

  • And, in the periods between actual, physical battles, our Earth and the other Earth would

  • have each other under constant surveillance.

  • Perhaps the problem would be resources, seeing as the second Earth could be turned into a

  • mining paradise - with visitors from our planet stripping it of all its earth-like materials,

  • in a bid to top up our own depleting reserves.

  • Clearly, ifEarth 2” was already populated by an intelligent species, this would be a

  • major point of tension - with either us taking advantage of them, or them of us.

  • But, of course, if this Counter-Earth actually was on the exact other side of the sun, then

  • getting there would be almost impossible in the first place.

  • Our Earth travels 584 million miles around the sun every year, meaning that the second

  • Earth would always be 292 million miles away.

  • Given that Mars was a measly 34 million miles away from us at its closest known approach

  • in 2003, and we've yet to figure out how to send people there, we'd need massive

  • technological advances to make the commute.

  • Perhaps the lack of terraforming required once we did arrive would be an equal trade-off

  • for the exceptional distancebut the journey would still demand whole generations of human

  • beings to be born, live and die on huge colonizing ships suspended in space.

  • The final destination could be a glorious, green utopia capable of hosting a population

  • of billions, full of new creatures to discover, places to explore and resources to enjoy.

  • But the paradise could also come at a cost, with the prospects of war, invasion and orbital

  • collision all clouding our connection with the brave new world.

  • And that's what would happen if there were two Earths in the solar system.

  • What do you think?

  • Is there anything we missed?

  • Let us know in the comments, check out these other clips from Unveiled, and make sure you

  • subscribe and ring the bell for our latest content.

What If There Were 2 Earths in the Solar System?

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What If We Had 2 Earths in the Solar System? | Unveiled

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    林峰生 posted on 2020/08/08
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