Returning from Geo-stationery Orbit

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In summary, a reverse escape from lunar gravity would be easier than dropping to Earth from geosynchronous. Geostationary orbit is about 22,000 miles above sea level, so a drop from there would require more velocity than dropping to Earth from geosynchronous. A drop from L1 would require 750 m/s, while a drop from geosynchronous requires 1500 m/s. Dropping from Earth-Moon Lagrange point 1 would be easier than dropping to Earth from geosynchronous.
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Chatterton
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I know when a Soyuz capsule returns from the ISS it has to orbit Earth a few times before re-entry due to all the momentum it borrowed from ISS.

What would happen if your ship was in the Clarke zone? Assuming we have the radiation shielding covered already. Would it be conceivable that a ship parked like that could just drop capsules in a fairly straight down manner? Assuming we have all the heat-shielding worked out.
 
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Chatterton said:
I know when a Soyuz capsule returns from the ISS it has to orbit Earth a few times before re-entry due to all the momentum it borrowed from ISS.

It's more because they don't want to carry the fuel required to de-orbit in less than a single orbit. Instead, they can break a little bit, fall towards Earth, and then use the air friction to slow them down further and further over successive orbits until the density of the air is high enough that they finally fall back to Earth instead of making another orbit.

Chatterton said:
What would happen if your ship was in the Clarke zone? Assuming we have the radiation shielding covered already. Would it be conceivable that a ship parked like that could just drop capsules in a fairly straight down manner? Assuming we have all the heat-shielding worked out.

No, because the ships would still be moving tangentially "around" the Earth. Firing a capsule straight towards the Earth would just result in an elliptical orbit since the capsule would retain all of the tangential velocity and gain an additional radial component.
 
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So, to do it right, my team of commandos will have to de-orbit the old fashioned way, spinning around the globe a few times before hopefully landing in relatively the same area, which would make even clumsier and more random than WWII paratrooper action and oh my God I think that cold be wicked cool. And it would take a while too, right? I think I remember something from Chris Hadfield's book about sleeping on the way down.
 
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Chatterton said:
So, to do it right, my team of commandos will have to de-orbit the old fashioned way, spinning around the globe a few times before hopefully landing in relatively the same area, which would make even clumsier and more random than WWII paratrooper action

Not necessarily. They could have control systems designed to keep them in close proximity prior to and during reentry.
Chatterton said:
And it would take a while too, right?

I'm not sure how long it would take. Geostationary orbit is about 22,000 miles above sea level, so I assume it would take a while, with the exact time depending on the velocity the capsules were launched at, the exact orbit, and a few other details.
 
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Chatterton said:
So, to do it right, my team of commandos will have to de-orbit the old fashioned way, spinning around the globe a few times before hopefully landing in relatively the same area, which would make even clumsier and more random than WWII paratrooper action and oh my God I think that cold be wicked cool. And it would take a while too, right? I think I remember something from Chris Hadfield's book about sleeping on the way down.

Consider a reverse escape from lunar gravity. Then your paratroopers can hang out in a bunker complex in lava tubes. You can also magnetic launch artillery. No need for explosives in the shells. Just crack the heat shield at the altitude you want. Between 2500 and 2600 m/s for Δv. If you give them 3,000 m/s they can launch at multiple angles and all arrive at once.

Dropping from Earth-Moon Lagrange point 1 is easier than dropping to Earth from geosynchronous. That can be done with 750 m/s. Geo requires around 1500 m/s before you can aerobrake. Launchers and fuel tanks sitting in geo are huge targets.
 
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Related to Returning from Geo-stationery Orbit

1) What is a Geo-stationary Orbit?

A Geo-stationary Orbit is a specific orbit around the Earth where a satellite appears to be stationary relative to a specific point on the Earth's surface. This is achieved by placing the satellite at an altitude of approximately 35,786 km above the equator, matching the Earth's rotation speed.

2) How do satellites return from Geo-stationary Orbit?

Satellites in Geo-stationary Orbit typically use their remaining fuel to perform a de-orbit burn, which lowers their altitude and allows them to re-enter the Earth's atmosphere. They may also be remotely commanded to release their remaining fuel and batteries to prevent potential hazards in space.

3) What happens to satellites after they return from Geo-stationary Orbit?

After a satellite successfully returns from Geo-stationary Orbit, it will either burn up in the Earth's atmosphere or be directed to a safe "graveyard" orbit where it will remain until it is no longer operational. This is to prevent potential collisions with other active satellites.

4) What are the benefits of returning satellites from Geo-stationary Orbit?

Returning satellites from Geo-stationary Orbit helps to reduce the amount of space debris in orbit, making it safer for future space missions. It also allows for the reuse of valuable resources, such as solar cells and other components, which can help to reduce the cost of future satellite missions.

5) Are there any challenges in returning satellites from Geo-stationary Orbit?

Returning satellites from Geo-stationary Orbit can be a complex and challenging task, as it requires precise calculations and maneuvers to ensure a safe de-orbit. It also requires careful planning to avoid potential collisions with other satellites or debris in orbit. However, with advanced technology and careful planning, it is possible to safely return satellites from Geo-stationary Orbit.

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