Since this is my first installment of my “the Science Behind it” series, I’d like to start off with an introduction. You can call me Bowan, EDScienceGuy, or Erectile Dysfunction Science Guy. I’m an engineer, amateur astrophotographer, and a huge science fiction nerd. I’m just going to go ahead and assume you all are too. I’m from the southern United States.

The purpose behind this and future posts will be to provide those who are curious with a “best guess” about the science behind the topics given to me by the community. I will also attempt to differentiate between the aspects of the game that are added for balance, immersion, or for simplicity’s sake. I feel the need to add that I am not a theoretical physicist I am also not affiliated with Frontier Development. Therefore the speculations I give regarding very theoretical principles should not be taken as completely accurate. I will, however, attempt to provide as accurate of information as I can. I will try to link sources so you can read more about the principles yourself. FRAME SHIFT YOUR MIND. By that, I mean use my posts as a springboard for your own scientific enlightenment. After you’re finished reading this and future posts, drink a beer, smoke something, or do what ever you like doing to feel the “woah” (do so responsibly).

So without further adieu:

The Science Behind It!

The vast majority of the questions the community had were about how we all get around the Elite: Dangerous universe. Fortunately, I know quite a bit about orbital mechanics and the math behind it. Unfortunately, the game does not incorporate relativistic orbital mechanics which is a blessing for many of us playing this game.

Sublight Sublight just means that your craft is operating below the speed of light. Simple enough. Here’s where it gets cool. Since the ships are able to scoop fuel from the sun, I can guess that it is probably some kind of hydrogen based fuel useful in fusion based power systems. So basically each ship has it’s own Holy Grail of power generation.

Since the drive and thrusters seem to both use electrical power for primary operation (providing thrust), and the thrusters look all flamey when in use (it’s a scientific term), I would guess that they use a kind of electromagnetic propulsion like Ion propulsion. Specifically potentially a future variant of the Hall Effect Thruster. TL;DR: Ion propulsion involves ionizing inert gasses (noble gasses) like xenon and electrically accelerating them (like a rail gun) to 30 km/s (that’s fast) before emitting them.

Unfortunately, the Ion Propulsion systems we have today are not suited for the high accelerations we see in ED. Maybe in the future they’ll be able to provide enough thrust to do everything we see in the game. Some in the community wondered about why our ships (once in motion) don’t stay in motion. First I’d like to say, “Good Catch!” As some of you may already know, while we operate in relativistic conditions, we fall under the laws of Newtonian Mechanics. These are Newton’s laws of motion:

Newton’s First Law of Motion : An object at rest tends to stay at rest until acted upon by an outside force. An object in motion tends to stay in motion in a straight line until acted upon by an outside force.

: An object at rest tends to stay at rest until acted upon by an outside force. An object in motion tends to stay in motion in a straight line until acted upon by an outside force. Newton’s Second Law of Motion: Describes how an object’s velocity changes when an external force is applied. F=m*a where F is the force applied, m is the mass of the object to which the force is being applied, and a is the acceleration that the object experiences because of the force. It may also be described as the change in momentum over the change in time. Momentum [P] is equal to an object’s velocity times the object’s mass or P=m*v. Since the change in mass (at low relativistic speeds) is negligible, it effectively becomes mass times the change in velocity over the change in time. F= dP/dt= d(m*v)/dt = m(dv/dt). In this formula, “d” indicates “a change in”. It’s really cool stuff.

Describes how an object’s velocity changes when an external force is applied. F=m*a where F is the force applied, m is the mass of the object to which the force is being applied, and a is the acceleration that the object experiences because of the force. It may also be described as the change in momentum over the change in time. Momentum [P] is equal to an object’s velocity times the object’s mass or P=m*v. Since the change in mass (at low relativistic speeds) is negligible, it effectively becomes mass times the change in velocity over the change in time. F= dP/dt= d(m*v)/dt = m(dv/dt). In this formula, “d” indicates “a change in”. It’s really cool stuff. Newton’s Third Law of Motion: For every action, there is an equal and opposite reaction. Basically the weight (force) you exert on the earth by standing on it, the earth exerts that force on you. In the context of space, if you and your best friend are hugging it out bro-style in space suits over the Earth when one of you decides to push the other away, you both fly away from each other. Neither of you will experience zero change in velocity. The change in velocity depends on your mass.

Now that we have those general principles explained, I can address the community’s questions. In reality, when a ship reaches 380 m/s in space it will continue onward at 380 m/s until it hits a space cow. The space cow in ED is usually an Anaconda or Type-9. When you see your velocity decreasing after a boost, this is just a mechanism of balance and control. The scale of this game (while very large) can be easily traversed at 380 m/s in a RES or around a station. At these speeds though, large objects come way too fast for a casual gamer to effectively avoid. So setting a speed limit can help. But that is just speculation. I am no game developer. Now I’m going to answer a few specific questions from the community: Redditor Literallysauron asked “In your view, how would an Adder versus Lakon Type-6 reenter atmosphere and take off from the surface again?” Well, there are ways. From an aerospace engineer’s standpoint, I would suggest keeping the Type-6 out of atmosphere. The shape of the body would require the craft to enter the atmosphere very slowly. If you notice, the surfaces likely to enter first have nooks and crannies that would make reentry unstable and unsafe.That would probably mean many large and controlled burns.This kind of power may be something easy to come by in the future, though. The flat surfaces and sharp edges would create a lot of problems for the craft if it were to enter at speeds that the Space Shuttle or many crafts do in sci-fi media. Lots of friction, lots of heat. As for the Adder, it would be a lot easier for it to enter a planet’s atmosphere. Its shape would be a lot like our space shuttle if it wasn’t for the transition to the flat bottom with low radius rounding. The shape of the incident surfaces is key to a safe and efficient re-entry. Spherical surfaces efficiently disperse thermal energy from friction, various forms of shock wave formation and their properties (General Compressible Flow and Reentry).

While friction is only a minor contributor to the dangerous conditions around reentry, one can more easily visualize the effects of shape on ease of entry when it is compared to sanding down a sharp corner on a block of wood with sand paper. The sharper a corner is, the easier it is to wear away at it. Roughly. The majority of the heat generated upon reentry comes from air being compressed, heated (the more a fluid is compressed, the hotter it gets), disassociated (broken down from molecules to atoms or ions), then sometimes turned into plasma. Interesting note, this is why there is a period of communications blackout with crafts that are entering or interacting with an atmosphere from orbit. Some crafts like the Mars Reconnaissance Orbiter, in order to save fuel, entered its final orbit around mars by “skipping” off of the Martian atmosphere, shedding velocity with resistance rather than a thruster burn.

Sharp surfaces don’t uniformly and efficiently disperse energy so one spot can be catastrophically destroyed by the heat and drag it experiences while the rest of the craft seems okay. This is the kind of thing that happened when Space Shuttle Columbia broke apart during reentry. A tile on the incident surface was damaged during take off therefore it’s dispersing qualities were ruined. I have a lot of problems with the viability of many of the spacecrafts in atmosphere. Only a few seem feasible but are restricted by the amount of thrust needed to counteract gravity instead of relying on lifting surfaces especially without any kind of anti-gravity or artificial gravity systems in place. If these crafts relied on shields to protect them from the harsh environment of reentry, I could get behind that if it were plausible. My ultimate guess is that it might be possible for both ships if the drives and thrusters on these ships are powerful enough to slow the decent and decrease the angular velocity at the same time. Another redditor reminded me that this would cause a controlled “drop”, but the ship would end up baking itself because it would be traveling into its (very hot) exhaust. By my experience in game, I don’t think they have sufficient thrust capabilities to do so. With limited thrust capabilities, a ship should rely on a controlled glide and drag to reduce its speed to a point that’s safe for landing. As for take off, I don’t know. I highly doubt it with the thrusters that exist on ships in the game. Utilizing lift is a no-go because most of the ships have little to no lifting surfaces. The amount of thrust needed to counteract gravity and just “ram” a large craft like the Saturn V or some of the ships in the game towards space would be enormous. Especially since there probably wouldn’t be any staging involved. [[Edit: I ran a small test in game to see how much force the engine provides. If the weight of the ships are in metric tons, the Anaconda’s boost -assuming there is very little change of mass involved- produces 71.4 Mega Newtons of force. Simple F=m*a. Mass of my ship is 1,286 Metric Tons, the time it took for the boost to max speed of 251 m/s was about 4.5 seconds. Since a is the change in speed over the change in time, F = 1289000kg * 251m/s / 4.5s. This tells me that it is plausible for some of these ships to overcome some planets’ gravities with a vertical take off.]] Thank you for reading my first installment. Please give me feedback in the comment section on the Reddit post or in the comment section. Tell me if there’s any thing I need to explain further, any info to change, or if my writing style is good enough. I do math. I don’t write (much). I plan on getting to the theories and concepts behind Supercruise and Jumping in the next one if the community has no major issue with this article and wants more. Again, feedback feedback feedback. I do ask that any criticism be constructive.