Can Canceling Orbital Motion Improve Rocket Efficiency?

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Discussion Overview

The discussion revolves around the concept of whether canceling a rocket's orbital motion relative to the Milky Way can enhance its energy efficiency for a given change in velocity relative to Earth. Participants explore theoretical implications, gravitational effects, and the complexities of motion within the galaxy.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants propose that accelerating a rocket to cancel Earth's orbital motion could improve energy efficiency, while others argue that from an Earthbound perspective, there is no advantage to this approach.
  • One participant mentions the concept of the "local standard of rest" and its relevance to high velocities in the context of the discussion.
  • There is a suggestion that the gravitational effects of the Sun and the galaxy would modify the rocket's trajectory, with implications for acceleration towards the galactic center.
  • Participants discuss the potential maximum change in velocity a rocket could achieve while falling towards the galactic barycenter after canceling its orbital velocity.
  • One participant questions the meaning of "anomalous acceleration" in the context of the discussion and its implications for trajectory calculations.
  • There are differing views on the necessary initial velocity from Earth to achieve escape velocity, with references to various sources providing different figures.
  • Concerns are raised about the complexities of calculating gravitational influences from local stars and the galaxy as a whole on the rocket's trajectory.
  • Some participants speculate about the possibility of reaching speeds close to the speed of light when approaching Sagittarius A*, while others clarify that relative velocity becomes ambiguous in curved spacetime.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the effectiveness of canceling orbital motion and the implications of gravitational influences, indicating that the discussion remains unresolved.

Contextual Notes

Participants note limitations in estimating gravitational effects and the complexities involved in calculating trajectories in a non-point mass galaxy. There is also uncertainty regarding the definitions and implications of terms like "anomalous acceleration."

  • #91
metastable said:
I was suggesting a way to possibly overcome the other problem that was mentioned (somewhat unpredictable in advance gravity wells), by using additional fuel.

In a practical sense, the problem you have is not needing more fuel to deal with unpredictable gravity wells. It's that you need really, really, really, really precise aiming of your trajectory from the start (which is impossible without knowing in advance where all those unpredictable gravity wells are), if you want to have any appreciable chance of passing by the galactic center and coming out all the way to the "outbound close approach" point on the other side.

In any case, this is developing into an open-ended series of questions on your part, not a well-defined question with a well-defined answer. So this thread is closed.
 

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