Page 102 - How It Works - Book Of Amazing Answers To Curious Questions, Volume 05-15

How will NASA blow up asteroids?

How NASA plans to save us from killer space rocks

t was 66 million years ago that the
dinosaurs’ reign on Earth came to an
Iend. The instigator was an asteroid, a
large lump of space rock of around ten
kilometres (six miles) in diameter, which
struck the Earth with a force that was one
billion times greater than that of the
Bomb detonation
Hiroshima bomb. Today, the destruction is
Now that the bomb is in place,
evident in the form of the Chicxulub impact the follower enters the crater and
crater in Mexico, approximately 20 Impact! detonates it, blowing the threat
The leading small kinetic to smithereens.
kilometres (12 miles) deep by 180
impactor collides with the target
kilometres (112 miles) wide. asteroid, creating a crater where
With asteroids tumbling through the a nuclear bomb follows a
Solar System and some coming close to millisecond later to land.
hitting our planet, it’s only a matter of time Ready to crash
until we end up experiencing the same fate Before it reaches the
asteroid, the leader
as the dinosaurs. That’s why we have to act portion of the spacecraft The asteroid
fast in order to get rid of a potentially needs to separate itself
hazardous asteroid before it gets to us. The from the follower. destroyer’s
solution? NASA’s Hypervelocity Asteroid
Intercept Vehicle, or HAIV for short, which A continual stream fl ight plan
works by blasting an Earth-bound chunk Once the HAIV has located the
of rock to smithereens with the help of a asteroid, the camera provides a The HAIV undergoes a series
continual stream of images of the of manoeuvres before it
nuclear bomb. target in case any correction destroys its quarry
HAIV will be coupled with an asteroid manoeuvres are needed.
warning system – even if there’s less than a
week until we’re hit by an asteroid, HAIV
can still be used, meaning that it’s never Sniffing out the threat
Now in space, the spacecraft seeks
too late to protect our planet. The
out the asteroid threat using its
spacecraft will be launched to rendezvous highly sensitive sensors and
with the target asteroid. It will then use an optical/infrared cameras.
impactor to carve out a crater and, only a
millisecond behind, a bomb follows to fit
inside the pre-drilled hole. The bomb then Follower and leader
detonates, shattering the asteroid into The spacecraft is made up of
millions of tiny pieces. two parts – the leader and the
follower. The leader holds the
Depending on how close the devastated
instruments such as the
asteroid is to Earth, it’s thought that the camera, while the follower is
fragments could still hit our planet in the the back-end of the spacecraft.
form of an intense meteor shower.
Ready for launch
However, provided that the fragments
When an asteroid is on its collision
were sufficiently small enough, we would path with Earth, the Hypervelocity
be largely unaffected as they would burn Asteroid Intercept Vehicle is
up in our atmosphere. launched on a rocket.
NASA’s Hypervelocity Asteroid Intercept
Vehicle would be launched on a high-
capacity rocket such as a Delta IV Heavy

© NASA

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