5 ms·

Adding sideways velocity shouldn't change your eccentricity, because it doesn't change the kinetic or potential energy of the orbit.

TeMPOraL 6y ago
But it does! Your orbit is defined by where your velocity vector is pointing at the moment. If you add a sideways component, you're a) increasing the magnitude, and b) rotating the vector.
- beervirus 6y ago
  Nope, but I see now why we're disagreeing. It's because the animation you linked to is misleading. Work is the dot product of force and velocity. If the thrust is always orthogonal to the velocity, then the burn does no work on the rocket, and so it can't increase the magnitude of the velocity. In the animation you linked, it's plotting out what would happen if you continue to burn due north for some period of time as your velocity vector changes. But you wouldn't do that--if you're trying to change your inclination, you burn perpendicular to your velocity, and as the direction of velocity changes, the direction of the burn changes too, such that it's always orthogonal. It's easy to watch this happen in the game if you don't use the maneuver node, but just use SAS to burn in the normal direction. The direction of "normal" changes during the course of the burn, and (except for small errors), your apoapsis and periapsis stay constant.
  - TeMPOraL 6y ago
    I see your point, but we're talking about two different things. Yes, you can rotate your orbit if you continuously burn in the direction orthogonal to your momentary velocity vector. In essence, this is the same thing the body below is doing to you already, with continuous acceleration in the radial direction. But we're talking about impact debris here, which do not accelerate under their own power. What happens is they get an impulse - a one-shot, near-instant change in velocity. If you just apply an impulse sideways, the eccentricity will increase, because your speed is now greater. The shape of your orbit around a spherical body is fully defined by your momentary position in 3D space and your speed. If your speed increases, the shape changes. KSP maneuver node planner shows what would happen to your orbit if you applied an impulse to it, of a configured magnitude and direction. It's not accounting for the burn time. Which makes it perfect for the purpose of talking about debris propelled by a collision.
    - beervirus 6y ago
      Ok, that's a good point.
    - smt1 6y ago
      i think but better ability to using sharing and ability to stabilize, you can recectified the characterization of the approximation of the differential geometry where more identicable smater to sweeep betweeen some limited bands hz and then also with generalizable ability to beam [software ecnoded:particles] to the necessary [newer conventions] so the complicated uncertainty propagation problem. just like your eyes have are not beaming k-vector spaces but feeling in the spectum of sesning so just like we have gained a lot of freqs you can think of it this way, lets say hypo just like two: let's just say instead of not sharing, we built the international telcommunication of unicode which has given us a more univeral crosstalk, it's usually events and viral id that is sometimes the unproblematic way to fix, for example: https://www.reuters.com/article/us-cyber-disinformation-facebook-twitter/facebook-twitter-dismantle-global-array-of-disinformation-networks-idUSKBN26T2XO https://www.reuters.com/article/us-cyber-disinformation-face... so the can just erase the linear case i could only describe as a event as a f-surface homology dag in some deformation theoric space but at least usually in academic theory of computing where the most semantic influnce is felt in usually kripian terms philosophically but you can see in the ppublic source code but privately data db but usually as you can se instead of focus history has shown our species has shown great research on the very historical 1d greek:pythagorean problem but now clearly see arxiv is a decent place to look. , so oyin applied , but i'm
mcint 6y ago
I think the argument is: It’s normal to the direction of travel, so it does increase velocity, and eccentricity is what you get when you add velocity at one point in an orbit. Same as other burns. If you were to burn retrograde of normal (but still tangent to the orbit’s radius), there’s an orientation where the retrograde component of your thrust matches the component in the component that’s...prograde in a new orbit. Which now sounds to me like it would just be 45° from retrograde, tangent to the radius

TeMPOraL 6y ago

But it does! Your orbit is defined by where your velocity vector is pointing at the moment. If you add a sideways component, you're a) increasing the magnitude, and b) rotating the vector.

beervirus 6y ago
Nope, but I see now why we're disagreeing. It's because the animation you linked to is misleading. Work is the dot product of force and velocity. If the thrust is always orthogonal to the velocity, then the burn does no work on the rocket, and so it can't increase the magnitude of the velocity. In the animation you linked, it's plotting out what would happen if you continue to burn due north for some period of time as your velocity vector changes. But you wouldn't do that--if you're trying to change your inclination, you burn perpendicular to your velocity, and as the direction of velocity changes, the direction of the burn changes too, such that it's always orthogonal. It's easy to watch this happen in the game if you don't use the maneuver node, but just use SAS to burn in the normal direction. The direction of "normal" changes during the course of the burn, and (except for small errors), your apoapsis and periapsis stay constant.
- TeMPOraL 6y ago
  I see your point, but we're talking about two different things. Yes, you can rotate your orbit if you continuously burn in the direction orthogonal to your momentary velocity vector. In essence, this is the same thing the body below is doing to you already, with continuous acceleration in the radial direction. But we're talking about impact debris here, which do not accelerate under their own power. What happens is they get an impulse - a one-shot, near-instant change in velocity. If you just apply an impulse sideways, the eccentricity will increase, because your speed is now greater. The shape of your orbit around a spherical body is fully defined by your momentary position in 3D space and your speed. If your speed increases, the shape changes. KSP maneuver node planner shows what would happen to your orbit if you applied an impulse to it, of a configured magnitude and direction. It's not accounting for the burn time. Which makes it perfect for the purpose of talking about debris propelled by a collision.
  - beervirus 6y ago
    Ok, that's a good point.
  - smt1 6y ago
    i think but better ability to using sharing and ability to stabilize, you can recectified the characterization of the approximation of the differential geometry where more identicable smater to sweeep betweeen some limited bands hz and then also with generalizable ability to beam [software ecnoded:particles] to the necessary [newer conventions] so the complicated uncertainty propagation problem. just like your eyes have are not beaming k-vector spaces but feeling in the spectum of sesning so just like we have gained a lot of freqs you can think of it this way, lets say hypo just like two: let's just say instead of not sharing, we built the international telcommunication of unicode which has given us a more univeral crosstalk, it's usually events and viral id that is sometimes the unproblematic way to fix, for example: https://www.reuters.com/article/us-cyber-disinformation-facebook-twitter/facebook-twitter-dismantle-global-array-of-disinformation-networks-idUSKBN26T2XO https://www.reuters.com/article/us-cyber-disinformation-face... so the can just erase the linear case i could only describe as a event as a f-surface homology dag in some deformation theoric space but at least usually in academic theory of computing where the most semantic influnce is felt in usually kripian terms philosophically but you can see in the ppublic source code but privately data db but usually as you can se instead of focus history has shown our species has shown great research on the very historical 1d greek:pythagorean problem but now clearly see arxiv is a decent place to look. , so oyin applied , but i'm

mcint 6y ago

I think the argument is: It’s normal to the direction of travel, so it does increase velocity, and eccentricity is what you get when you add velocity at one point in an orbit. Same as other burns. If you were to burn retrograde of normal (but still tangent to the orbit’s radius), there’s an orientation where the retrograde component of your thrust matches the component in the component that’s...prograde in a new orbit. Which now sounds to me like it would just be 45° from retrograde, tangent to the radius