Nice, sensible explanation. That was always one of the things in the back of my mind as a dub. Everything physical decays, it cannot last forever.
I don't claim to know what God has planned for the future, but it can't be as the dubs claim.
I think it's easier to believe that the earth will last forever when you are young and feel indestructible. As you get older, it just becomes obvious that it is not how life works.
I watched a show on the Hubble telescope the other night and the universe is amazing. We have such a small view of things here on the earth. It's easy to get attached when all we've ever known is here on this earth. There is so much more we don't know and have not experienced.