This is great. I have never done any physics since third year of high school, but with these videos I am so interested and I pick it up so quickly. Mike, you are truly doing an amazing job, the graphics, the voice-over, the explenation in easy to understand language, it's all amazing.
@@xianxion9214 Totally agree with you, I'm 17 and want to learn a bit about orbital mechanic and this channel is pure gold ! For now everything is clear and "easily" understandable, thanks Mike for sharing your knowledge 🤜💥
Just found your "Let's do the Math" playlist, man, it's so dope ! Truely loving it, hope you will continue this ! By the way I would be interested to see a video of you explaining the math behind suicide burns, you are such a good teacher :)
i'm using these formulas to plan a voyager recreation using the outer planets mod, it's currently going well. im in middle school and i love physics and math, so these kinds of videos are incredibly helpful, hands-on and overall fun.
Simple. Use a protractor held to your screen to see if the angle between planets at the time is the one you calculated. If it is, you're clear for launch.
I just spent the past 40 or so minites making a spreadsheet of every phase angle going from any planet to any planet, and any moon to any other moon in that system. I wish Google Sheets had a third axis so I could put the trip costs, too.
Especially given the elliptical orbits, you'd be better off simulating orbital elements and doing something like a gradient descent algorithm to find optimal condiitons. I'm sure there is an analytical solution but I imagine it's fiendish.
I like how KSP is basically a physics class disguised as a game. And while its nice to know the math. A math illiterate like me would much rather use a mod and have the computer calculate the proper launch window.
@MikeAben Thank you for these outstanding videos! One question: I think we are still missing one piece of information necessary to calculate our interplanetary transfer. We have delta-V and the phase angle from your videos, but how do we know where exactly to do this burn? In other words, in our origin orbit (Kerbin orbit in this case), where/when exactly do we do the burn? (I’ve read some sources that call this the “ejection angle”.) Thank you!
It can be worked out, but you don't need an ejection angle in game. I typically don't use this number in my games. When moving inwards towards the sun (Moho or Eve) you want to eject from Kerbin’s SOI in a retrograde direction relative Kerbin’s orbit about the sun. This will have you ejecting across the day side of Kerbin. When moving outwards (Duna, Dres or Jool), the ejection will cross the night side. When setting up the ejection in game, just put the maneuver on the correct side of Kerbin and put in the required dV for the transfer. Then simply tweak the timing of the maneuver until the periapsis with the sun (or apoapsis) is at it lowest (or highest) point. You are now at the correct ejection angle.
@@MikeAben Thank you for your reply! I'd love to figure out how to calculate it manually if possible. Do you have any good sources you could point to for how to calculate it? That well-known KSP calculator (I won't link, since RU-vid seems to be eating my comments when I try to link) provides the ejection angle, but the guide it's based on from the KSP forums is now degraded/unreadable due to images no longer being hosted. I've also been studying the Bate, Mueller, and White astrodynamics textbook, but I still cannot figure out how to calculate the ejection angle. Any pointers would be appreciated; thank you again for the great videos!
@@jameskostas-kraines2362 The only site I can think of is this one. www.braeunig.us/space/index.htm It has a nice orbital mechanics section, though I'm not sure if it deals with what you need. Thinking on this since your comment, the problem is more involved than the phase angle problem. You want to leave Kerbin's SOI either going prograde relative to Kerbin's orbit, or retrograde (depending on which way you are heading). You then need to work out how far ahead prograde or retrograde you need to be at LKO when making the burn. This will depend upon the dV of the ejection burn. The higher the dV, the quicker you'll exit Kerbin's SOI, which reduces the necessary angle from prograde or retrograde. I'm not sure how to approach it from there. Good luck in your search.
@@MikeAben Thank you, I think that website has everything we need to calculate this! Specifically, for future searchers: on the INTERPLANETARY FLIGHT page, the Escape from Earth's Sphere of Influence section gives us gamma, which is the "zenith angle of the departure asymptote" for the hyperbolic orbit departing the origin planet. From this angle, the info in your videos, and that website's ORBITAL MECHANICS page, "The Hyperbolic Orbit" section, we can calculate the true anomaly of the periapsis for that hyperbolic orbit, which tells us exactly where to do the burn. I'll report back here if that ends up being insufficient, but I think that's everything we need!
ok but what if you can't approximate the orbit as a circle? What do then? I want to hit an asteroid with perihelion of 13*10^9 and apohelion of 57*10^3 m (abut 1 and 4.4 au). Wolphram doesn't want to use Kepler formula for some readon.
Phase angle would be useless in this situation as it would always be changing as the object moved about its orbit. I would eject myself from Kerbin when it is directly below the target's apoapsis aiming to get my periapsis with the sun to match up with the target periapsis. At periapsis you should be able to do a retrograde burn that will get you an encounter after doing one more orbit of the sun. I do sort of the same thing around Kerbin in this video. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-QJafTwiRUco.html This may be a good topic for a future tutorial.
You'd probably want to numerically approximate in this case, using a gradient descent algorithm to perturb the three burn axes to minimise distance from the target.
You actually sound a lot like another YT'er that does tutorials for NMS. He doesn't go as in depth with the maths but he does explain concepts that might be difficult to comprehend for the more casual players. Just saying....
@@MikeAben Well,imagine you are building a colony on mars,and imagine first lets say rover is launch,and then second but that second rover needs to launch in the same position as other rover. In ksp there is trajectory mod,but when you dont want to use trajectory mod or you are playing other games,Then its hard to make colony. Sorry for my english
