Not having much in the way of a scientific mind. Why is a transit of Venus so rare? Since Venus orbits inside Earths orbit, and on the same plane(?) then wouldn’t tranists be yearly.
Well it would be a regular event, more than once a year provided Venus and Earth orbits were in precisely the same plane. If Venus is just above or below the sun from our POV there is no transit.
That’s the whole point. They are not on the same plane. Venus’s orbit is tilted by about 3.39 degrees with respect to the Earth’s orbital plane (the ecliptic).
So most times Venus is between us and the sun, it is either above or below the sun from our viewpoint.