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1. How Will SpaceX Send Human To Mars And
Reduce Cost Of Space Travel? How Does
Falcon 9 Work?
For as long as humans have walked on this earth we have stared into the black
expanse of space. Wondering where our place in the universe was and why we are
here? The rhythm of the moon's phases has guided humanity for the millennium but
Galileo was the first to point a telescope towards it and identify its mountains and
craters. Not just that he saw that those distant heavenly bodies had moons of their own.

2. A discovery that shocked the religious worldview of our place in the universe. Fast
forward three hundred years when we've landed twelve men on our moon. An
achievement that was largely driven forward in a world living in the shadow of a threat of
global nuclear war. Since that wrath has subsided our raised to expand into space has
waned the merry Society put it best with their founding statement. Civilizations like
people thrive and challenge and decay without it.
The time has passed for human societies to use war as driving stress for technological
progress. As the world moves towards unity we must join together, not a mutual
passivity but in common enterprise. Facing outward to embrace a greater and nobler
challenge than that which we previously posed to each other. Pioneering Mars will
provide such a challenge. One man has embraced that challenge like no other and his
name is Elon Musk. Today we're going to investigate how will SpaceX get us to Mars?
Goal Of Elon Musk

3. Elon Musk's ultimate goal is to reduce the cost of space travel. He believes that he can
get the cost of a ticket to Mars down to around half a million USD. The overlap of people
who actually want to go to Mars and the people who can actually afford it will be great
enough to form the Mars colony. The most efficient way that is the one that uses the
least amount of fuel to get to Mars from Earth is with the home and transfer method
named after Walter Holman who first proposed the idea in 1925.
With this method, you wait for the earth to be at its closest point to the Sun and then
launch. Mars needs to be about 44.4 degrees ahead of Earth so that Mars will be at its
most distant point from the Sun when the vehicle arrives. This alignment happens once
every 26 months. This is not the shortest or the fastest path to Mars but requires the
least amount of energy input when getting the cost of travel down this is the deciding
factor.
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2020
The space shuttle could transfer one kilo to low-earth orbit for about $18,000. The
Falcon 9 can do the same for just 2,700 and SpaceX is continuously working to reduce
that cost. Let's take a look at the Falcon nines launch sequence and learn some of the
ways SpaceX has reduced the cost of operation.
How does the Falcon 9 work?
The Falcon 9 first stage is powered by nine Merlin engines these engines have the
highest thrust to weight ratio of an e booster engine ever made at 155 to one this means
the engines can lift more with less fuel and dude faster. At launch, the nine engines
produced 7900 kilonewtons of thrust lifting the 550-tonne rocket off the ground and
gradually accelerating it to five times the speed of sound. This section called inter stage
houses another Merlin engine that is designed to work optimally in the vacuum of
space.
Related Articles: Why Elon Musk Chose Stainless Steel To Build SpaceX's
Starship

4. The first stage now separates about 75 kilometers above our planet's surface and
reveals the second stage engine. It's interesting to note that interstage remains
connected to the first stage after separation. This was not the case for the Saturn 5 as
interstage needed to wait for the engines of the second stage the fire before separating
using pyrotechnic charges this ensured a clean separation. As there were worries that
the interstage would collide with the engines as it separated due to clearance issues.
This is not a problem with the Falcon 9 making the interstage reusable and again saving
money. The Merlin engine of the second stage is designed to be shut down and
restarted multiple times to deliver the payload to the appropriate orbit or increase the
velocity enough to perform the Hohmann transfer to Mars. The payload is stored inside
the composite fairing which is big enough to fit a school bus. When the time is ripe the
fairing splits in half and drifts away from the second stage, the payload is now released
into orbit around Earth.
Meanwhile, the first stage is begun its descent back down to earth, coal gas thrusters
fired flip it around. Once this maneuver is complete the engines will fire again to bring
the speed down free entry and give an appropriate trajectory to reach the landing site.
Upon reentry, the grid fins deploy which provide aerodynamic control allowing it to steer.
These are fantastic little devices that provide excellent control at supersonic speeds.
This mesh structure provides a huge amount of control surface area in a small amount
of space which allows them to be he stowed away during launch to reduce drag. Grid
fins are also much shorter than conventional planar fins so they generate fewer hinge
moments. Meaning they need smaller motors to control them in a high-speed flow. As
the first stage descends closer to sea level the cold thrusters grid fins and Merlin
engines work together to control the precise landing on the drone ship barge. The
reason SpaceX uses this barge is another cost-saving measure.
The Falcon 9 launches from Elon towards the sea for safety reasons. When the first
stage separates is over open ocean and if it needed to return to land it would need to
slow down, turn around and use more fuel to get back to where it started. Instead, the
drone-ship can place itself at the predicted landing zone and wait for the first stage. This

5. way the Falcon 9 just needs a little bit of extra fuel to slow itself down to land. Most
people see SpaceX's true innovation in the reusable rocket but their innovation in the
manufacturing field is just significant.
How SpaceX Will Reduce The Cost Of
Space Travel?
SpaceX was the first space company to employ a method called vertical integration to
manufacture their rockets. This means that SpaceX designs and manufactures nearly
all of its components itself. The Merlin engines, the aluminum-lithium fuel tanks, the
composite fairing for holding the payloads, the Dragon spacecraft. the flight computers
and the coding that goes into them, they are all designed and manufactured by SpaceX.
Comparing this to the space shuttle Rockwell developed the orbiter Lockheed, Martin
developed external tank and ATK developed the solid rocket boosters. Each of these
companies has their own sub-contractors too - this adds a huge amount of cost on to
the final price tag. Each sub-contractor adds a Marco percentage to their selling price in
order to make their own profit. Manufacturing everything yourself eliminates all of these
price markups. It cuts out the middleman, like buying popcorn as kernels and clocking
them yourself rather than buying them from the cinema for $10. But has the added
benefit of allowing you to have full control of your quality control and create an efficient
product development system. All of your employees can speak and collaborate to
improve and develop new designs.
Elon insists on open plan offices to remove any communication barriers. He himself
works in a cubicle, this creates the perfect environment for continual innovation and if
we want to get to Mars that is going to have to happen. So you may be wondering
what's next for SpaceX?
They will be launching their Falcon 9 heavy variant at the end of the year. According to
SpaceX the Falcon 9 can currently launch one kilo to Mars for 15,400 Dollars. But the
heavy variant can launch one kilo for about 6,600 Dollars. The average American

6. weighs 80 kg ignoring all other costs like how you live on Mars or how you'll survive the
journey there. The raw price for a one-way trip to Mars will be about a half million
dollars. Musk aims to bring the price for a roundtrip, including all other expenses to
Mars down to half a million total.
In 2010, SpaceX presented concept designs for future heavy-lift rockets that will help
towards that goal. They're also planning to replace the nine Merlin engines of the Falcon
9 with one incredibly powerful engine dubbed the Merlin 2, that will increase the thrust
to weight ratio even more. Currently, we are excited to see what Elon Musk and his
incredible employees have in store for us.