Colossal Questions.
Is time travel even possible?
Let's start with what you can't do.
There's a really good chance that we
can't travel back to, say, the invention of the wheel,
not just because it's mean to steal a caveman's invention,
but because experts believe that it's actually not
physically possible to go backwards in time.
In very basic terms, this is because we'd
need a bridge between the past and the present
in order to travel back in time, like a wormhole.
A wormhole is a concept that Albert Einstein
came up with back in the 1930s.
They act like shortcuts that connect
two distant spots in space.
Scientists in the 1980s added to this theory
by suggesting that wormholes might
be able to be used like a time machine.
Even if that were true, there are some pretty big problems
with traveling back in time that way.
The main problem is that we don't
know how to make wormholes yet.
And even if we did, you'd only be
able to travel back in time to the moment
the wormhole was created.
And since cavemen probably spent more time
hunting saber-tooth tigers than they did creating wormholes,
we probably won't be traveling back there anytime
soon, because there's just no way to get there.
Traveling into the future, on the other hand,
is a much more likely possibility.
This is thanks to one of Einstein's theories
called time dilation.
The physics of space and time can get pretty confusing,
but the basic idea is that time passes more slowly for a moving
clock than it does for one that's staying still.
Pretty cool, but what does that mean
for traveling into the future?
Well, imagine you got into a spaceship
and flew super, super fast through the galaxy.
Since time moves more slowly as you fly at warp speed,
time would pass faster for people on Earth
than it would for you.
So by the time you return back to Earth,
you would be in the future.
And they say science isn't cool.
Is there alien life in outer space?
OK, guys.
Let's start with something you might not be expecting.
There's actually a pretty good chance that aliens do exist.
Space is so enormously huge that the chance
of there being intelligent life somewhere in outer space
is pretty good.
That's because there's billions and billions of planets
in our galaxy alone, and some of those
are considered Earth-like by NASA,
because they have a lot of the same conditions as Earth.
Scientists have been searching for Earth-like planets that
can support life, and they're finding some pretty cool stuff.
In 2015, a NASA mission found the first planet
that might be a candidate for supporting life.
The terribly-named planet.
Kepler-452B, which they're calling Earth 2.0,
is about the same size as Earth and is
the right distance from its sun to support intelligent life.
It likely even has a rocky surface that
could support water and plants.
And Earth 2.0 isn't the only candidate for alien life.
As recently as February 2017, NASA
discovered seven more Earth-like planets
while searching through space.
OK, so there's a planet out there
that's really similar to Earth.
But what does that have to do with aliens?
To understand that, you need to know the basic ingredients that
create life on Earth--
water, basic elements like carbon or nitrogen,
and an energy source, like the sun.
It doesn't matter if you're talking about a microscopic bug
or a big blue whale.
All life on Earth is created using
these same general ingredients.
That's why scientists have focused
on planets that are Earth-like.
If all the ingredients that we know can create life
are there, then maybe, just maybe, they'll find aliens.
So have we found alien life yet?
No, we haven't.
But space is a really, really, really big place.
And our instruments for searching the galaxy
are pretty limited today.
So it's likely that aliens exist somewhere in space.
It's just going to take lots of searching to find them.
And that won't stop us from trying.
Maybe the coolest attempt so far happened
in 1977, when NASA launched a space probe called Voyager 1.
The probe was launched carrying a Golden
Record for an alien civilization to find and listen to.
The hope is that if the Voyager spacecraft is ever
discovered by an alien race, it'll
be a great way for them to learn about us
and find where we live.
It contains greetings in 55 languages,
Earth sounds like volcanoes, wind, rain, frogs, elephants,
a heartbeat, Morse code, a train, a tractor,
and even a kiss.
It also contains pieces of traditional music
from different cultures, recordings
of brain waves, 116 pictures detailing human life,
and even directions back to Earth.
Every day, Voyager 1 floats further away from Earth.
And the Golden Record on board should
stay in playable condition for over a billion years.
In the 40 years since Voyager 1 was launched,
it has traveled more than 11 trillion miles through space,
which is nothing compared to how big the galaxy is.
So if there are aliens flying through space,
let's just hope they happen to pass by our little puttering
probe and come say hi.
Can human beings have real superpowers
like you see in comic books?
Guys, I have some really awesome news for you.
You can have superpowers.
Generally speaking, there's three main ways that characters
get superpowers.
You can be a mutant, an altered human, or a tech genius.
You could also be a robot, an alien, or have magic,
but the first two aren't human, and magic isn't real,
so we're going to ignore those.
Mutants are characters like the X-Men who are
born with their superpowers.
There's been many people born with mutant powers,
but probably the best example is a little German boy
with super strength.
His real name is unknown, but he goes by what's already
basically a superhero name--
Das Uberboy.
Yup.
That little German boy was jacked.
He has a genetic mutation that messes with how
big his muscles can grow.
At just four years old, Das Uberboy
could lift six times more weight than the average kid.
OK, so you could be a real-life mutant.
But what about spiders, or gamma rays, or radioactive waste?
Can they give you real life powers?
Yeah, they can.
Altered humans like Spider-Man or Captain America
are characters who somehow gain their superpowers
after birth, usually in some scientific mishap.
Cutting-edge science is showing that there may actually
be a way to change someone's DNA and give them
superpowers in real life.
It's all theoretical at this point,
but the best hope for gaining superpowers after birth
is a process called quantum tunneling.
This mysterious regeneration process
is responsible for the metamorphosis of tadpoles
into frogs, for instance.
Scientists are just beginning to understand quantum tunneling,
but some believe it could allow humans to quickly
recover from terrible injuries, like Wolverine or Deadpool.
So super strength and regeneration are cool.
But what about the superhuman gadgets?
In the comics, a tech genius is someone like Iron Man or Batman
who get their powers from high-tech devices, usually
of their own brilliant design.
It turns out to be harder than Tony Stark makes
it look to build an exosuit.
Currently, there's just one working prototype
on the planet, and it isn't nearly as cool
as it is in the movies.
It was built to help soldiers take
long distances without feeling the weight
of their heavy equipment.
The exosuit offsets most of that weight, which
help soldiers conserve energy.
So we might be a couple of decades away from anything
resembling a Bruce Wayne invention, But.
There definitely are companies working on it.
So not only can you have superpowers in real life,
there's all kinds of different superpowers to choose from.
So figure out your favorite superpower
and get to work mastering it.
And now you know that you can have real superpowers.
What's the deal with 3:00 AM?
And is it actually scary?
Well, for all the spooky stories surrounding 3:00 AM,
the truth is there's really nothing all
that special about it.
Like most internet memes, it's just silly fun.
This one started way, way back in June 2017.
YouTuber Ruby Rube started making videos
where she told viewers not to try certain tasks at 3:00 AM,
like making slime, using a fidget spinner,
and calling the Boss Baby.
Since then, Do Not Try This at 3:00 AM and other videos
in the style have popped up all over YouTube,
spreading the superstition that scary things can
happen at 3:00 AM, so long as you film it
and put it on YouTube.
But superstitions like these go back way further
than YouTube videos.
Since at least the late 1500s, there
have been superstitions surrounding the witching
hour-- the time of night where witches, ghosts, demons,
and ghouls are at their most powerful.
That's right.
According to superstition, witches and other creepy
creatures cast their strongest spells, hexes, and black magic
at midnight.
In some early Christian versions of the legend,
the witching hour is at 3:00 AM, as a way
for demons to mock the importance of the Holy Trinity
in Christianity.
So is 3:00 AM really unlucky or dangerous?
No, it's not.
But it can be scary to be up in the middle of the night
when there's weird noises, and no one's up,
and the shadows on the wall are creepy,
and it's super, super dark.
So you can see why people have told all sorts of scary stories
about it.
When did people start calling seven lucky,
and why did it catch on?
Nobody can quite pinpoint exactly when people first
started thinking of seven as a lucky number.
Experts believe it may have to do with the fact
that lots of different cultures across the world
happen to have a positive relationship to the number
seven.
There's seven days in a week, seven traditional colors
in a rainbow, seven continents, and seven wonders
of the ancient world, just to name
a few of the uncanny connections to the number seven.
Over time, the number took on even more meaning,
as religions across the world started
getting in on the magic of our lucky number.
Seven often represents perfection or completion
in the Christian Bible.
There are seven heavens in Judaism and Islam,
and in Confucianism, it represents
the combination of yin and yang and wuxing,
or the five elements.
Scientists have also shown that the number seven is connected
to the way we think, too.
You see, your brain can only remember up
to seven things at a time.
Any more than that and it needs to break it up
into smaller groups.
So you can see why people might start to think
of seven as a lucky number.
If our brains think of seven as a complete number,
and if our world is full of meaningful uses of the number
seven, it's no wonder people like that number.
So is seven actually lucky?
Eh, probably not.
But clearly, it's more than just your average number.
How do those things known as the Venus flytrap actually
eat the flies they trap?
The Venus flytrap is a strange plant that only grows naturally
in the coastal bogs of North and South Carolina in the United
States, basically in a 60-mile radius
around the city of Wilmington.
It's called a flytrap, because as you probably know,
it's famous for trapping flies in its toothy leaves
and might be the most well-known carnivorous plant.
But it's far from the only one.
That's right.
There are actually around 630 different species
of meat-eating plants scattered across the planet.
But don't freak out.
There's no giant freaky flower out there eating people, just
small plants eating lots of flies, beetles, spiders,
and other insects.
Carnivorous plants use a bunch of different methods
to catch bugs--
pitfall traps that lure them in with sweet
smells only to trap them inside, flypaper
traps that lure prey to a sticky surface, lobster pot traps that
are easy to enter but hard to exit,
and, of course, snap traps, like our friend the Venus flytrap.
Plants like this have a big leaf divided into two
and hinged in the middle with long trigger hairs
coming off the end.
The plant then lets off a sweet smell that attracts insects
and tempts them to get close.
Whenever a bug finally touches one of the hairs,
the plant snaps shut.
Once a bug is trapped inside, the flytrap
starts to ooze out stuff that help break it down quickly,
until it becomes a goopy, soupy liquid
that the plant can absorb.
Like any other plant, the Venus flytrap
still gets energy from the sun and soil
through photosynthesis.
But it grows in poor, wet, swampy dirt.
That's where the flies come in.
What the bogs lack in good soil, they more than make up
for in insects.
So over time, the flytrap evolved
to eat the bugs that were plentiful to make up
for the energy that's missing.
Believe it or not, the Venus flytrap
is on the verge of becoming an endangered species.
This is partially due to human development and habitat
destruction.
But more than anything, it's due to poachers
who steal the plants to sell.
So while they may seem pesky, thorny, or even downright mean,
Venus flytrap are our friends, and we should make an effort
to keep them safe.
At least in the real world.
Ah, game over.
Have you ever stopped and wondered why so many of us
love to be scared?
Experts can't say for certain, but most
believe that we love scary stories, movies,
and even frightening experiences because deep down, we
know, in the back of our brains, that we're in no real danger.
You see, most of the time, our minds
do a pretty good job of sorting out
real risks from imaginary ones.
As we grow up, we learn to instinctually understand
the difference between real and fake.
That's why so many of us can have
fun walking through a haunted house attraction at a theme
park, or watch a super scary movie with all the lights off.
We know that there's no real threat.
Worst case scenario, you'll give yourself a nightmare.
But even in the scariest moments,
you know deep down that it's all fun and games.
Sure, the physical reaction to a scary scene
might feel like the real thing.
Your heart will probably beat faster,
your hair might stand on end, you might shudder or shiver,
and you might even scream bloody murder.
But there's a couple key differences
to a fake scare that keeps us having fun
without true terror setting in.
You see, when you're scared--
for real or for fun--
your fight or flight instinct kicks in.
When that happens, your body releases all kinds of hormones
and adrenaline to help you through the scary situation.
But the chemicals released are different
depending on if the fear is real or make-believe.
In a real-life scary situation, your body
releases hormones that help make you stronger and much more
aware in the moment to help you survive
your spine-chilling circumstances.
But when you're just watching a movie,
your body releases different hormones
that just make you feel good.
Experts think that's one of the big reasons
lots of us laugh after a big spooky scene in a movie,
or after a jump scare at a haunted house.
Our body is pumped full of a feel-good chemical called
dopamine.
Of course, that's not the case for everyone.
Some people hate getting scared no matter what.
Why?
Well, no one can say for sure, but lots of experts
think it's because their bodies don't release as much dopamine
when they're scared.
With less dopamine coursing through their veins,
they literally get all the scares without any of the fun.
No wonder they don't want to watch that horror
movie on Halloween.
So next time your friend is cowering in the corner
as you fire up your favorite scary show,
maybe just throw on a comedy.
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