Why planet's orbit is not perpendicular or random ? It always seems each planet is revolving on the same geometric-plane around the star.
So, I am a 15 year old interested into astronomy. My father used to have a reflector telescope, but was never so serious about it that he could recommend me a good telescope. I am looking to buy a ...
Why do planets rotate around a star in a specific elliptical orbit with the star at one of it's foci? Why isn't the orbit a circle?
How do you find the distance from a star/planet/black hole to another? I know people can calculate the distance from Earth to a star, but what about from one to another?