Yes, the apparent direction of the interstellar wind is due to the motion of our solar system through a 30-light-year-wide cloud of gas [1]. The specific dynam

Yes, the apparent direction of the interstellar wind is due to the motion of our solar system through a 30-light-year-wide cloud of gas [1]. The specific dynamics of the cloud (e.g., its turbulence) are still largely unknown, though the fact that the direction of intersellar wind has shifted by several degrees over a few decades hints that it’s not totally calm. I’m not sure about solar sails outside the heliosphere... that’s an interesting question. I’m not an expert, just a guy who likes reading about this stuff. [1]: https://en.wikipedia.org/wiki/Local_Interstellar_Cloud https://en.wikipedia.org/wiki/Local_Interstellar_Cloud