This blog will be discussing the fundamentals of orbital maneuvers. This is a hobby of mine that I enjoy studying from time to time.
Maneuvering in space can be made into a very fine art, if you are interested in efficiency. Efficiency, in point of fact, tends to be a paramount concern. While you can in fact simply point your vessel towards your destination and fire your engines until you get there, this is extremely wasteful in terms of fuel (though it is very fast). Though there are efficient methods of travel that involve continuous burns, this involves very high specific impulse and low thrust engines. The high thrust variant wont be remarked upon here in any great length. Fear not however, specific impulse and thrust will be explained, most likely in the first section.
In this blog I will cover five main topics pertaining to this.
Ascent:
Given the planet-bound nature of our civilization in this day and age, lifting our various fancy machinery from the planet into orbit is a key element of space travel in all regards. Nobody is able to do serious fabrication in orbit of yet, however that may one day become a reality. For now, however, we need to make things down here.
The silver bullet for efficient ascent right now is a fully re-usable cargo rocket. Most payloads are delivered to orbit atop rockets that cost sixty million (USD) or more to produce. These devices are generally allowed to crash unceremoniously into the ocean at high velocities. Currently SpaceX pegs the fuel cost at approximately $200,000 per launch. As you can probably infer, being able to recover the launch system fully intact and operational would cheapen space flight quite a bit.
Orbital Maneuvers and Key Locations:
Once you have escaped the atmosphere, you generally want to go somewhere specific. There are many such places. You might want to rendezvous with a space station, position yourself in some kind of constellation relative to other sattelites, or position for some kind of transfer to another celestial body. Finally, you might want to travel to a Lagrange Point. If you picked L4 or L5, then you can be reasonably certain your devices debris will be admired millions of years from now (how rude).
Planet-Moon transfers and Maneuvers:
This is somewhat distinct from transferring to another planet. It is generally simpler, and is somewhat similar to an orbital rendezvous, except with the destination having an appreciable amount of gravity. There are a number of fly-by and insertion maneuvers you can attempt to pull off, especially if you hypothetically add more moons. I may have some fun with this one and play around with some wacky less-than-sane but efficient options.
Basic Interplanetary Transfers:
In this section I will talk about the idea of transfer windows and some of the more straightforward options for transferring from one body to another. This is distinct from Planet-Moon transfers in that you are escaping from your home planets gravity well and transferring into that of another. Its a fundamentally different process in some ways, and is somewhat like the difference between a trip downtown and a multi-state road-trip. More speed, more complex navigation, much further from home.
Advanced Interplanetary Transfers:
I'll be honest, this probably wont be explained in as great a detail due to the great diversity of options here. Grabbing fifty gravity assists on a twenty year trip that loops all over the system is going to be different every mission. The only real common theme is the term 'gravity assist' and being Ebenezer Scrooge with every last millimeter of Delta-V. I will mention how new kinds of engines are effecting the use of these sorts of trajectories.
sorry for getting this up a little late
Maneuvering in space can be made into a very fine art, if you are interested in efficiency. Efficiency, in point of fact, tends to be a paramount concern. While you can in fact simply point your vessel towards your destination and fire your engines until you get there, this is extremely wasteful in terms of fuel (though it is very fast). Though there are efficient methods of travel that involve continuous burns, this involves very high specific impulse and low thrust engines. The high thrust variant wont be remarked upon here in any great length. Fear not however, specific impulse and thrust will be explained, most likely in the first section.
In this blog I will cover five main topics pertaining to this.
Ascent:
Given the planet-bound nature of our civilization in this day and age, lifting our various fancy machinery from the planet into orbit is a key element of space travel in all regards. Nobody is able to do serious fabrication in orbit of yet, however that may one day become a reality. For now, however, we need to make things down here.
The silver bullet for efficient ascent right now is a fully re-usable cargo rocket. Most payloads are delivered to orbit atop rockets that cost sixty million (USD) or more to produce. These devices are generally allowed to crash unceremoniously into the ocean at high velocities. Currently SpaceX pegs the fuel cost at approximately $200,000 per launch. As you can probably infer, being able to recover the launch system fully intact and operational would cheapen space flight quite a bit.
Orbital Maneuvers and Key Locations:
Once you have escaped the atmosphere, you generally want to go somewhere specific. There are many such places. You might want to rendezvous with a space station, position yourself in some kind of constellation relative to other sattelites, or position for some kind of transfer to another celestial body. Finally, you might want to travel to a Lagrange Point. If you picked L4 or L5, then you can be reasonably certain your devices debris will be admired millions of years from now (how rude).
Planet-Moon transfers and Maneuvers:
This is somewhat distinct from transferring to another planet. It is generally simpler, and is somewhat similar to an orbital rendezvous, except with the destination having an appreciable amount of gravity. There are a number of fly-by and insertion maneuvers you can attempt to pull off, especially if you hypothetically add more moons. I may have some fun with this one and play around with some wacky less-than-sane but efficient options.
Basic Interplanetary Transfers:
In this section I will talk about the idea of transfer windows and some of the more straightforward options for transferring from one body to another. This is distinct from Planet-Moon transfers in that you are escaping from your home planets gravity well and transferring into that of another. Its a fundamentally different process in some ways, and is somewhat like the difference between a trip downtown and a multi-state road-trip. More speed, more complex navigation, much further from home.
Advanced Interplanetary Transfers:
I'll be honest, this probably wont be explained in as great a detail due to the great diversity of options here. Grabbing fifty gravity assists on a twenty year trip that loops all over the system is going to be different every mission. The only real common theme is the term 'gravity assist' and being Ebenezer Scrooge with every last millimeter of Delta-V. I will mention how new kinds of engines are effecting the use of these sorts of trajectories.
sorry for getting this up a little late
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