Here at The Infographics Show we like to investigate
life-altering enigmas and crucial issues,
such as how you could defeat Jason Voorhees,
or the best life hacks for surviving a zombie
attack.
Yet while our teams of world class researchers,
historians, philosophers and undead experts
are busy finding new and exciting matters
to look into, what we really love is answering
questions directly from you, our viewers!
Today we're going to be answering a question
by Wayne, who emailed us asking, what would
happen if an asteroid was hurtling towards
the earth and we exploded a nuclear device
in space to stop it?
Well, we're going to tell you!
Join us as we dive into the worlds of astrophysics,
nuclear technology, and simple mechanics to
find out, what would happen if we detonated
a nuke in space?
Let’s set the scene.
A giant asteroid is speeding towards the earth,
humanity seems doomed, and since world governments
in this scenario are following the direction
of Michael Bay, the solution they have come
up with to stop a speeding asteroid is detonating
a nuclear device in space.
As the brave and surprisingly attractive men
and women on this mission tearfully start
their nuclear bomb planting and detonation
journey, they leave the earth’s atmosphere
and enter the vacuum of space, where they
encounter the enemy asteroid and push the
button to blast it into smithereens with their
nuke.
First of all, what would this blast even look
like?
Most of us are familiar with the “mushroom
cloud” look of a nuclear blast, but in space,
this would look entirely different.
When a nuclear bomb goes off, it releases
a massive amount of radiation.
When this radiation comes into contact with
air on earth, it rapidly expands the air,
causing the classic blast wave that destroys
everything around a nuke.
In space, with no air around, there would
be no blast wave, just a spherical-looking
rapid, soundless explosion of light, heat,
and radiation in every direction.
The nuclear bomb’s radiation, in the form
of gamma rays and X-rays, would affect a much
larger radius in space than on Earth, as there
is no atmosphere to slow down or disrupt its
spread.
The good news is, there are much fewer humans
in space than on Earth that will experience
this radiation.
The bad news is, the radiation would also
make its way down to Earth’s atmosphere
in no time.
Side effects of the blast would be seen on
the planet almost immediately.
Charged particles from the nuclear bomb would
interact with Earth’s magnetic field, creating
ribbons of light that would stick around for
hours or even days, depending on the blast
size.
Imagine seeing the Northern Lights, but less
Instagram-friendly and more expansive and
terrifying.
In addition, debris from the blast and the
asteroid would rain down into the atmosphere,
though most fragments from the bomb itself
would burn up and just leave heavy ions behind
in the planet’s atmosphere.
The fragments from the asteroid, depending
on its size, are a different story we will
address soon.
As a side effect of a nuclear blast in space,
most power sources and electronics on Earth
under the blast area would be shut off, and
there would be disruptions in navigation systems.
High-speed, highly charged electrons from
the detonation would create a dense but powerful
magnetic field known as an electromagnetic
pulse - EMP for short.
The EMP would disrupt the flow of electricity
for hundreds of miles around the blast.
How do we know this for sure?
Well, because the US already detonated a nuke
in space.
That’s right; during the Cold War arms race,
the US was worried that the Soviets would
launch nuclear bombs into space to stop US
intercontinental ballistic missiles.
Naturally, the US then set up Project Fishbowl
so they themselves could test the effects
of nuclear explosions in space.
One fine morning on July 9, 1962, the US mounted
a W49 thermonuclear warhead on a Thor rocket
to conduct a test known as Starfish Prime.
It was launched from Johnston Island, 900
miles (1500 kilometers) southwest of Hawaii,
past the upper atmosphere.
At 9:00 AM GMT time, 11:00 PM in Hawaii, when
the missile was on its way back down and had
reached 240 miles (400 kilometers) above sea
level, the US detonated the nuke.
The explosion released 1.4 megatons of energy.
This means the blast unleashed the energy
equivalent of 1.4 million tons of TNT.
Because it took place in space, this massive
energy burst was strangely soundless.
It caused a spherical blast that created an
aurora for over a thousand miles in almost
every direction.
The effects of the exploding nuke were much
larger and emerged much further away than
US scientists had ever anticipated.
The electromagnetic impulse generated by the
blast changed the flow of electricity in Hawaii,
900 miles away - roughly the distance from
New York City to Orlando, Florida.
While people in Hawaii getting ready to sleep
suddenly wondered why the Northern Lights
had moved several dozen degrees lower in latitude,
they were quickly distracted by blown out
streetlights, radio and telephone outages,
and a whole host of other electronic malfunctions.
The nuclear bomb’s detonation, done close
to the altitude of the International Space
Station, which orbits at 254 miles above sea
level, caused extensive satellite damage as
well.
The high-speed, high-powered electrons moving
through the atmosphere hit at least six satellites,
causing malfunctions that eventually made
them fail.
This was in 1962, when the Earth had much
fewer satellites in its orbit.
Today, a nuclear blast in space would probably
hit hundreds of satellites.
As of 2018, there are 4,987 satellites orbiting
Earth, and 1,957 of them are operational.
This means a nuclear blast in space would
not only send a huge surge of light and radiation
charging through the Earth’s atmosphere,
but also disrupt your Sirius XM Deep Tracks
radio station.
All things considered, messed up radio stations
and a weird hours-long light show would be
worth it to save the Earth from a major, homo
sapiens-destroying catastrophe, right?
Well, it’s not that simple.
Depending on where the nuclear bomb has to
be detonated - for example, if the location
happens to be right over a country - the resulting
damage could disable a whole country, if not
several, in one blow, by disrupting communications
and electronic functions.
If satellites are hit, this disruption could
go on for an extremely long time.
But wait - would a nuclear bomb even break
apart an asteroid?
And more importantly, would breaking it apart
even save the Earth in the first place?
Most known asteroids in our solar system are
found in the asteroid belt, where they orbit
the sun between the orbits of Mars and Jupiter.
Scientists believe that asteroids are the
remains of planetesimals, which were early
pieces of the solar system.
Some asteroids are primitive, unchanged pieces
of the original solar system that never formed
into larger bodies, while others are remains
of differentiated pieces of the solar system,
smashed to bits by Jupiter’s strong gravity.
While many asteroids mind their own business
orbiting within the asteroid belt, some are
affected by outside gravitational pulls and
flung out, settling into different orbits
around the solar system.
If an asteroid is big enough to pose a threat
to at least part of humanity, it means it
must be at least 1,312 feet (400 meters) in
diameter.
6.2 miles (10 kilometers) in diameter is the
threshold for “extinction class” asteroids,
which pose a much larger existential threat.
Extinction class is the nice scientific way
of saying everything on earth would be dead
if an asteroid that big collided with our
planet, except maybe cockroaches and Keith
Richards.
The asteroid that caused the Chicxulub Impact
and wiped out three quarters of plant and
animal life on the planet 66 million years
ago, including the dinosaurs, was at least
6 miles (10 kilometers) in diameter, with
some scientists theorizing it was up to 50.3
miles (80.9 kilometers) long.
The bad news is, plenty of asteroids in this
“extinction class” still exist, rocketing
all around space.
The largest known asteroid, Ceres, is a whopping
294 miles (473 kilometers) in diameter, or
almost 48 times larger than the size needed
to end us.
The good news is, sizeable asteroids rarely
collide with the Earth, only around once every
160,000 years according to NASA scientists.
Also according to NASA, detonating a nuclear
bomb planted at or beneath the surface of
a large asteroid, even an asteroid at the
bare minimum threshold of 1,312 feet, would
just cause the asteroid to break apart into
still-large pieces rather than obliterate
it.
These asteroid chunks might continue racing
towards the earth, and still be big enough
to cause significant damage.
NASA believes it would be very difficult,
if not outright impossible, to determine the
way in which a nuke would break an asteroid
apart, so there’s little hope of controlling
the size of the fractured pieces.
Factors like size, center of gravity, and
material - some asteroids contain carbon while
others are made of iron or stony iron - would
affect the way an asteroid would fracture,
in mostly unpredictable ways.
However, a nuclear device could still be used
to guide asteroids away from earth through
deflection.
In fact, NASA scientists think this would
be the best way to use nuclear bombs to avoid
colossal damage to humanity and the planet
by rogue asteroids.
While surface and subsurface explosions would
probably just split the asteroid, nuclear
bombs that explode near, but not on the asteroid,
in a process called standoff explosions, would
hopefully release enough energy to change
the asteroid’s course.
Thus, the recommended strategy for winning
People v. Asteroid is a series of standoff
nuclear explosions to push the asteroid another
way.
We might end up with a shattered moon, but
that’s a risk we’ll take.
Is there any real chance we’ll have to use
this strategy soon?
Well, scientists think it’s unlikely, as
the probability of a large asteroid hitting
our Earth in the near future is slim.
However, the Apophis asteroid, even though
it’s relatively small at 1,100 feet (340
meters), is worrying a few governments.
It’s projected to pass within 19,000 miles
(31,000 kilometers) of Earth’s surface on
April 13, 2029.
Even though this seems like a massive distance,
it’s relatively close in space terms.
If you make the comparison, the moon is 238,900
miles (384,470 kilometers) away from Earth.
The fact that Apophis is swinging by the Earth
on Friday the 13th probably doesn’t help
ease peoples’ fears.
However, most scientists are looking at this
event as a data-gathering bonanza, as objects
that large rarely make their way towards Earth.
Still, director of the Russian Federal Space
Agency, Anatoly Perminov, announced in 2009
that Russia will brainstorm ways of deflecting
Apophis if it should come too close.
Of course, Apophis isn’t the only sizeable
asteroid making its way around the universe.
Which is why NASA’s Planetary Defense Coordination
Office exists.
It may sound like a division of Star Trek,
but the PDCO is a real agency that uses technology
like telescopes and radar to map out the orbits
of existing asteroids and detect new ones.
Asteroids’ movements are compared to known
constants like background stars in order to
estimate the speed and direction of their
orbit.
Radar is then used to obtain information about
the size and shape of an asteroid.
So if the PDCO detects an incoming asteroid
emergency, would detonating nuclear weapons
to stop them still be on the table?
Sorry to disappoint fans of explosions, but
that’s unlikely.
If it helps, the existing options sound even
more interesting.
Lindley Johnson of the PDCO assures us that
technologies such as kinetic impactors and
gravity tractors would be used to divert the
asteroid.
A kinetic impactor is a special high-speed
spacecraft that collides into an asteroid
to push it onto another path, while a gravity
tractor is a spacecraft that flies alongside
an asteroid, using its own gravity to pull
the asteroid in another direction.
We’ve got more great videos with answers
to your burning questions so click the video
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