Here we will be concerning ourselves with the transit of a planet with it's parent sun.
I have a few questions that I am not sure about:
1) Do all planets transit their parent sun? It would seem to me that if all planets "cross" their parent star in some form, then depending on our point of view, we should be able to see the transits. For example, we never see a Mars transit, but if we alter our point of view to be farther then mars, then we would.
2) If all the planets are in the same orbital plane, would the transit of one, imply the transit of all the others? For example, our solar system is relevatily in the same plane, and it seems like Mercury/Venus transit, would also imply earth and beyond transits. We just have to be in right perspective.
3) If a planet transits its star, does the probability of a transit increase/decrease/same if planet semi major axis changes? I am not sure about this one. I still think that it would be 100% the fact that a transit will occur, but its more unlikely that we would ever see it, because we need our angle to be just right.
4) If a planetary system has multiple planets, would we detect transits from several planets if they are all in the same orbital plane, or if they have different orbital planes? This kind of builds off of #2, and I think the answer is the same orbital plane, because the "different" orbital planes could be such that are 90 degrees from our point of view, meaning we would never see the transit.
I want to know if my understanding of transits is correct by these questions. Thanks!