I'd be interested more about the steering (attitude control). Where did you find that? I don't see it in the article. It seems like the dominant force here is

I'd be interested more about the steering (attitude control). Where did you find that? I don't see it in the article. It seems like the dominant force here is going to be the radiation pressure of the laser hitting it, at least in deep space. There isn't going to be solar wind for most of this journey, they will be past the heliosphere and in the interstellar medium. But I guess all you need is for it to be correctly oriented when it reaches the distant star?