Sci Fi is in it’s very nature, is fictional
science, and pushing the boundaries of the
real world is what makes it so awesome.
But, in order for the stories to be at all
believable, they are usually bound by the
physics of the universe we know and love,
otherwise everything would be flying marshmallow
unicorns spurting caramel, exactly… it wouldn’t
make any sense.
So for now, let’s step away from the science
fiction and get a healthy does of science
fact, and find who’s getting it all wrong
on the silver screen.
I’m Stu, this is Debunked and we’re here
to sort the truths from the myths and the
facts from the misconceptions.
Let’s kick things off with a bang… literally
Whether it’s an intergalactic dog fight
blasting ships out of space or undocking complications
that end in catastrophe, space movies love
a burning fireball of an explosion.
Except, they wouldn’t look like you, and
many movie directors, probably imagine them
to. Fire is caused by the combustion of gases
in air, and as we all know there’s not a
great deal of the stuff in space.
In order for fire to exist it needs an oxidizer,
but that doesn’t necessarily need to be
air. It could take the form of liquid oxygen
or hydrogen on the spacecraft.
So the laser blast that’s tearing open the
ship could cause one of the oxygen tanks to
combust. However, the fire can only last as
long as the oxidizer does and it would all
be burned up in an instant, meaning you wouldn’t
get the ‘Bayhem’ style explosion the IMAX
is designed for.
In fact an explosion in space would look more
like this…
...a short burst of spherical light. The force
of the explosion would still be powerful,
it just wouldn’t look as dramatic.
And it wouldn’t matter how powerful the
explosion, not even a nuclear bomb could satisfy
Michael Bay’s intergalactic pyrotechnical
needs, how do I know?
Well, they tried it, not for yet another installment
of Transformers,
but instead for a series of experiments called
Operation Dominic during the cold war in the
early 1960s.
The program of atmospheric tests saw a 1.4
megaton bomb detonate 250 miles above the
earth. And it looked like this…devastatingly
beautiful but not the fireball you normally
see
This brings us onto another thing that is
always done wrong...
the deafening sound of this sort of explosion
wouldn’t actually be heard at all, because
Ridley Scott was right. “In space, no one
can hear your scream”,
And they also wouldn’t hear you explode.
Sound travels by banging a load of molecules
into each other, but as we’ve just discovered
there aren’t the traditional molecules like
air for sound to vibrate through in the vacuum
of space
And here’s an expert to debunk what I’ve just said, about space being a vacuum.
 
 
Now that might sound like a lot more molecules
per cubic centimeter than you’d expected
in space, but for comparison air is around
a thousand million million times more dense.
So sound CAN travel in space, it’s just
not dense enough so that we can hear it.
But to be honest I think audiences would prefer
they continue to take dramatic license on
this one, unless you’re into silent battle
scenes.
Although, Kubrick got it right in 2001: A
Space Odyssey.
But this doesn’t mean the universe is in
total silence everywhere except on earth.
Where there IS atmosphere, there’s sound.
But again it wouldn’t sound how you’d
expect.
On Mars, for instance, sound will be higher
in pitch, which would make “The Martian”
more of a comedy
and could explain why Marvin The Martian talks
like he does.
Now let's head away from Mars, like they do
in the movies… really really fast."
Now, we’re not here to debate the science
behind actually achieving light speed, warp
speed or...
That’s for another video.
What we’re going to look at here is the
acceleration of getting to any of these speeds.
Now the problem with getting a spacecraft to
- Light speed for example, are the passengers inside it.
Now, when the ship is suddenly ‘jumped’
to 186,000 miles per second (299,338 KMPS),
inertia would cause Han Solo quite the problem,
because he would be thrown back in to his
seat with such force that he’d spatter all
over the freshly cleaned leather. ..as an
astrophysicist from NASA, explains
So if we wanted to see Chewie and the crew
arrive in one piece, then according to author
Jeanne Cavelos a former NASA astrophysicist,
accelerating safely to lightspeed couldn’t
be done in an instant, it would actually...
take months.
The level of g force that a human can safely
withstand is around 9 gs, and this is only
for a very short period. Anything longer than
a few seconds, and you will pass out and die.
This is because the number of gs you experience,
makes your body feel THAT many times heavier,
so at 9 gs, you feel 9 times heavier, and
so will everything inside you, meaning your
heart will struggle to pump this heavier blood
to your brain.
Cavelos suggests accelerating at more survivable
3gs to get up to light speed (something we
can normally only suffer for around an hour).
But even travelling at 3 gs it would take
two and half months to reach light speed.
Hardly thrilling viewing.
But what does have you firmly planted at the
edge of your seat is stuff like this…
Located between Jupiter and Mars, our Asteroid
Belt (or main asteroid belt) is usually referred
to as a dense circular field of asteroids
that’s near impossible to pass through.
And to be fair when you look at a diagram
of it, you’d be forgiven for believing the
worrisome droid.
There ARE up to a MILLION asteroids that are
OVER a kilometer in diameter! And understandably
you’d want to avoid crashing in to one.
But the truth is, each asteroid is also several
kilometers apart from one another, several
MILLION Kilometers apart in fact.
So far, that if you were stood on one, it’s
likely you’d not even be able to see your
neighbouring asteroid,
AND if you combined the total mass of the
entire asteroid belt it would only equate
to around 4% of our moon.
According to David Morrison from the NASA
Ames Research Center, the average 1 kilometer
asteroid only suffers a collision once every BILLION years.
So, far from being impossible to navigate
your way through the asteroid belt, you would
actually have to go out of your way to hit one.
