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Comment by Mesisio | Hacker News Reader

Interesting though.

Does that really matter without air resistance?

Depending on how high you actually bring it. Like 500km away from earth is still an orbit (I think that's Hubble's orbit) but how much force do you need or will happen?

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Rockets can easily accelerate with enough force to kill a human (cargo flights and unmanned flights use different launch profiles for this reason).

The less Gs you need to design a component for, the lighter/simpler it can be, so why unfurl early and add that extra mass and complexity to the design?

When rockets are firing lots of acceleration is applied that the delicate structures are only designed to handle when stowed. Think long arms on hinges. They can take acceleration in one axis, but not at 90 degrees to it.

I guess the acceleration needed to leave orbit might need so much more fuel if you need to do it slowly than doing it fast?

Otherwise it would just take longer.

Rocket engines could only be throttled down to certain power and manoeuvring thrusters would run out of propellant way before it reaches any orbit. Maybe something like electric propulsion can do it but it will take very long time to make it practical imho.

The parts of a ship that thrusters are directly attached to experience acceleration first, the other parts that are further out from the thrusters won't accelerate immediately and if the acceleration is too sudden or extreme could be damaged or break off entirely.

And to answer your question in the other response, many thrusters have a minimum thrust, and even that minimum may be too much for the parts when deployed.

By definition, as long as thrusters are firing, you are accelerating.

Acceleration is defined as the change in velocity, and velocity is defined as the change in position (w.r.t. some inertial reference frame). There will always be some bending when thrust is applied at one part of a body; nothing is perfectly rigid.

As an extreme example, imagine a stick one lightyear in length: if we ignite a rocket on one end, firing perpendicular to the stick's length, then the other end cannot start moving for at least a year.

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