The higest res blue marble texture is actualy the highest res satelite footage of the entire globe ever done! Thet doesent mean there arent data for higher res just not for the entire globe... And the 2* 21,600 *21,600 (on request) available form nasa is absolutely mindboglingly big!
But if you need a zoom into this effect then even thats not enough. Now the trick is to be intelligent. By layering a local map on a good res entire planet map and maybe a enven more local in center of that is by faar the only computationaly intteligent way of doing it.