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  • Life goals: meet an alien or at least answer the question; are we alone in the universe?

  • What I’m saying is WHERE ARE ALL THE ALIENS?

  • Hey guys, Julia here for DNews

  • Probability tells us that our galaxy should be teeming with life. Our universe is about

  • 14 billion years old. Our Solar System and our Earth are only 4.5 billion years old.

  • But the universe is a big place, and there are plenty of other solar systems that are

  • wayyy older even in our own galaxy. So intelligent life should have evolved millions of years

  • sooner than we did and they should have taken over the galaxy by now. At that rate, we should

  • have some evidence that the truth, or life, is out there. So what’s the deal with the

  • radio silence? This is the very question physicist Enrico Fermi asked in the 1950s, specifically

  • Where is everybody?”. This idea that alien life should be out there, but we haven’t

  • heard anything is called the Fermi Paradox.

  • Most solutions to the paradox can be broken down into two broad categories, aliens don’t

  • exist, or they do exist.

  • If aliens don’t exist, it might be because a planet that can sustain life is rare, and

  • that complex life-- such as plants and animals-- would evolve is even RARER. This is creatively

  • called the Rare Earth Hypothesis, which suggests that we are actually alone. Another idea is

  • that an intelligent, colonizing, intergalactic lifeform is incredibly rare. Robin Dale Hanson,

  • an associate professor of economics at George Mason University, described this idea asThe

  • Great Filter’.

  • He suggests that each stage of evolution might just be really hard to reach. For aliens evolve

  • and become visible to us, they would need the right star system, reproductive molecules

  • like RNA, simple life, complex life, sexual reproduction, multicellular life, tool using

  • life, where we are now, and last but not least, colonization explosion, or the ability to

  • take over the galaxy. He suggests each of these steps is very improbable, let alone

  • all of them. And one or more of these steps isthe Great Filter”, meaning that it’s

  • so incredibly difficult to pass, that nothing in the universe has done it.

  • Since weve already made it through most of these steps, it stands to reason that the

  • biggest hurdle ofThe Great Filtermight be where we are now or where we nearly are.

  • If that’s the case, that means we are approaching the filter.. and odds are, we will destroy

  • ourselves before we become interstellar, just like everyone else in the universe probably

  • did.

  • But okay what if aliens DO exist? Where are they? One hypothesis supported by Author Michael

  • Michaud is that aliens are just shutting the hell up. And for good reason, self protection.

  • The universe could be a giant hostile place filled with warfaring colonizing civilizations.

  • So by staying at home and staying quiet, they aren’t drawing attention to themselves to

  • keep themselves safe.

  • But some people think extraterrestrial life is here. And that maybe they just don’t

  • care. Maybe they don’t find us interesting enough. Or maybe theyre nice aliens, who

  • care about us a whole lot. So much so that they won’t even touch us. One theory published

  • in the journal Icarus in 1973 suggests that we are part of some sort of protected zone,

  • almost like a preserve or a zoo! But maybe they ARE here and reaching out to

  • us. But we just can’t communicate with them, maybe were just bad at reading the signs.

  • Maybe they communicate with technologies that are different from radio waves, like lasers,

  • or something we haven’t even conceived yet!

  • There’s so many more solutions to the Fermi paradox, one physicist Stephen Webb lists

  • at least 50 solutions in his bookIf the Universe Is Teeming with Aliens ... WHERE

  • IS EVERYBODY?”. But he actually believes we are alone.

  • No matter what, I want to believe were not alone. But perhaps the universe is too

  • vast for us to ever know.

  • While we haven’t heard anything from other civilizations that doesn’t mean well

  • stop scanning the skies anytime soon. In fact, NASA’s got a new telescope in the works

  • that will see further than weve ever seen before.

  • If you want an incredible behind-the-scenes look at the new James Webb Space Telescope,

  • make sure to check out Discovery’s brand new documentary Telescope! The world premiere

  • is this Saturday, February 20 at 9pm on the Discovery Channel. Well be watching too!

  • So what do you think? Do you think life is out there? Or what’s your favorite solution

  • to the paradox? Let us know down in the comments below

Life goals: meet an alien or at least answer the question; are we alone in the universe?

Subtitles and keywords

B2 H-INT US universe life paradox filter galaxy fermi

Why Haven't Aliens Found Us Yet?

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    林奉毅   posted on 2016/05/13
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