What space simulators are the most accurate at simulating real world physics?

We've all at least heard of KSP, a popular space flight simulator. its not the best but can teach someone the basics at rocket science, delta V, burntime, basic orbital maneuvers, retrograde, prograde, etc. but we all know its also not very accurate, because of how it has on rails and physics simulations at once.

by accurate i mean most similar to real life ex: in KSP atmospheric drag just cuts off in this more accurate simulation it is a long gradient.

My question is what simulations are more accurate at simulation?

• Are you asking about commercially available simulations? NASA has some good ones for training the crew. Mar 27, 2020 at 18:03
• really just what ones are the best Mar 27, 2020 at 18:04
• ive clarified it a bit Mar 27, 2020 at 18:15
• It is probably worth noting that KSP can be made significantly more accurate with mods. Principia adds full Newtonian gravity, and FAR adds a more realistic aerodynamics model Mar 28, 2020 at 18:32
• @OscarSmith what does "full Newtonian gravity" mean exactly? When I hear that I assume that there are no more patched conics and it's full n-body, since Newton's gravitational force falls of as $1/r^2$ it never goes to zero. Is that really what Principia adds? fyi I've asked Will Kerbal Space Program 2 have Lagrange points, halo orbits, and other 3-body goodies?. It was well received but currently closed as "primarily opinion based" but I think it can be reopened if there is some news! update: Oh, Principia was mentioned there already.
– uhoh
Mar 29, 2020 at 18:49

1 Answer

Well, I think this is a good question.

Orbiter 2016 and its 2006 and 2010 predeccessors are fairly realistic spaceflight simulators.

Since you ask about physics:

1. It has a Newtonian physics engine with adaptive order of integration of linear and angular states (Runge-Kutta and symplectic integrators to order 8)
2. Dynamic inclusion of gravity sources from multiple solar system objects (allows e.g. simulation of Lagrange point orbits). From what I could find, KSP only uses a patched conic approximation to Newtonian gravity, so Lagrangian points do not exist.
3. Non-spherical gravity sources are also considered.
4. Gravity gradient torque on objects with anisotropic inertia tensors due to inhomogeneous gravitational field is also simulated.
5. Radiation pressure can be user-defined, so you can fly solar sails around. There are add-ons for this, if you don't want to code it yourself.
6. Atmospheric phase of flight is also accurate. Surface winds can be enabled, dyanamic pressure is simulated well and spacecraft can be configured to sustain airframe damage (if you're too reckless).
7. Orbiter 2016 now performs sub-sampling of critical frames for higher numerical precision. This becomes particularly important during surface collisions, where forces change rapidly over short time scales.

References:

• Thanx, I was glad to learn of Orbiter. My comment on KSP is that by the time you learn how to run KSP, you could have learned to integrate a = F/m in MATLAB. Mar 28, 2020 at 19:42
• thank you for the answer, definitely solves my problem. Mar 29, 2020 at 17:38