On the other hand, a proposed spaceport to be located on the A'Mhoine Peninsula in Sutherland, in the far north of Scotland, is in an ideal location to utilise small, vertical launch rockets to take satellites into the polar orbits required for Earth observation.
https://space.blog.gov.uk/2022/03/16/on-the-ground-with-space-hub-sutherland-and-orbex/
Due to the Earth's rotation, a satellite in polar orbit will eventually pass over all of the Earth's surface so can gather information about the entire Earth.
Yes, for polar orbits latitude doesn't matter at all. But aren't we discussing Artemis, TLI's, escape velcity etc.?
Best regards!
Best regards!
Even Mount Everest at 8,850 m is lower than the 12,000 m launch altitude of Pegasus from its carrier aircraft.
Our discussions can be wide ranging. One thing leads to another and everything leads to enlightenment in regard to space exploration. 🙂
P.S. Kay, I wasn't contradicting your statement, but simply introducing a different scenario - as indicated by "On the other hand".
Escape velocity is the velocity required to escape the gravitational pull of the earth. It has nothing to do with the atmosphere.
Rockets are propelled by conservation of momentum. And they burn oxygenated fuel so no atmosphere is required.
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The atmosphere is actualy a drag, wastes energy and prevents the use of rail gun launchers (although such devices maybe ideal for use in launching material mined off the moons surface, they could be solar powered perhaps)
That link took me to the Ideal Rocket Equation variously attributed to the Russian Constantin Tsiolkovsky, the American Robert Goddard and others.
Delta-V or ΔV is derived through conservation of momentum.
For every unit of fuel ejected from the rocket, the rocket and the remaining fuel gains momentum.
If we wanted the rocket to gain even more momentum, we could simply load on more fuel so that we have more to eject.
However, there's a problem as each unit of fuel has to accelerate not only the mass of the rocket, but also the mass of the remaining fuel!
This means that the more fuel that is carried, the less effective each unit is at providing the rocket with momentum – it’s a problem of diminishing returns.
The greater the delta-V required, the greater the mass ratio between wet mass (full of fuel) and dry mass (empty tanks) that is required, and the more difficult the rocket will be to engineer.
Using integral calculus to model this problem of the rocket accelerating as its mass diminishes gives us the Ideal Rocket Equation.
Now, I understand conservation of momentum, but there's no argument that this is rocket science! 🚀
I've extracted the above information from the following source which also provides numerical examples relating to real rockets:
https://www.marssociety.ca/2021/01/07/rocket-physics-the-rocket-equation/
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Getting out of Earth's Gravity Well needs much fuel and expensive Boosts.
But after that everything is free. Hydrogen, Oxygen, Sunlight for Electric Panels. Building materials. And Powerful Fusion Rockets can't be too far down the line.This is what the Rocket Scientists have realised.
We just ride Lagrange points to get around, albeit with minor course corrections. Maybe Electric Rockets. Regard Chaos as a feature of the Universe rather than a bug. Employ the Butterfly Effect in that small changes make a big difference.
https://en.wikipedia.org/wiki/39P/Oterma
https://en.wikipedia.org/wiki/Genesis_(spacecraft)
The Interplanetary Superhighway aka ITN:
https://en.wikipedia.org/wiki/Interplanetary_Transport_Network
Quantum Mechanics and General Relativity have always been the Glamour Performers of Physics, but many secrets lurk in stodgy old Classical Mechanics.
https://www.amazon.co.uk/Calculating-Cosmos-Mathematics-Unveils-Universe/dp/1781254311
Hope I condensed a complex subject well there.
🙂
But after that everything is free. Hydrogen, Oxygen, Sunlight for Electric Panels. Building materials. And Powerful Fusion Rockets can't be too far down the line.This is what the Rocket Scientists have realised.
We just ride Lagrange points to get around, albeit with minor course corrections. Maybe Electric Rockets. Regard Chaos as a feature of the Universe rather than a bug. Employ the Butterfly Effect in that small changes make a big difference.
https://en.wikipedia.org/wiki/39P/Oterma
https://en.wikipedia.org/wiki/Genesis_(spacecraft)
The Interplanetary Superhighway aka ITN:
https://en.wikipedia.org/wiki/Interplanetary_Transport_Network
Quantum Mechanics and General Relativity have always been the Glamour Performers of Physics, but many secrets lurk in stodgy old Classical Mechanics.
https://www.amazon.co.uk/Calculating-Cosmos-Mathematics-Unveils-Universe/dp/1781254311
Hope I condensed a complex subject well there.
🙂
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Very nice, thank you.
Absent any gravitational field, space travel is pretty much a free ride. Minor course corrections require small amounts of fuel compared to escaping a planet's gravitational field.
Any space trip is a precisely choreographed event.
Absent any gravitational field, space travel is pretty much a free ride. Minor course corrections require small amounts of fuel compared to escaping a planet's gravitational field.
Any space trip is a precisely choreographed event.
It's fun to explore these ideas!
NASA has studied the possibility of using a railgun as a potential launch system.
The railgun operates according to Fleming's Left Hand Rule for conventional current.
First finger for Field direction, seCond finger for Current direction and thuMb for Movement direction.
https://www.wired.com/2014/08/the-physics-of-the-railgun/
