How do I zoom in on a planet from space to ground level? I have made a pretty decent planet earth but would like to know if there's a decent tutorial or way of getting from space and going through the atmosphere to ground level. I am not sure of the best approach. I was thinking either make a really detailed section of the planet that I plan to see up close, make a second mesh more detailed at the point of ground level or pause the animation point, delete the less detailed earth and then only recreate the section visible to the camera. All 3 of these could be wrong I don't know. Would one of these methods be the best way or are there other ways to achieve what I am trying to do?
I would make it into few scenes that I would then merge in post-production.

Scene 1 - from space, getting close to planet, you could have sunflare, satellite or whatever cover view for a moment, so you could load Scene 2 then.

Scene 2 - Scene 2 starts exactly where Scene 1 ended, with more detailed planet done. It would be going from planet to some upper atmosphere clouds, at point in time cloud would cover view, that is the moment when you start scene 3

Scene 3 - starts exactly where Scene 2 ended, with same cloud covering the scene, but with much more detailed ground and you getting even closer.

And basically that would be it - each time you'd want to increase your details you would have to find a way to cover view for a fraction of a second to switch scenes seamlessly. This way you could do it all the way to the ground and beyond :)