Genesis 8:22 “While the earth remains, Seedtime and harvest, Cold and heat, Winter and summer, And day and night Shall not cease.”
God alone has appointed the time that this earth will remain and He alone controls what will happen after that point and even before it, what lies ahead.
He has promised us that we do not need to worry that this earth will fall apart or that it will be obliterated by some random comet passing by or that it will stop spinning and let us all fly off!
We have His word on this and that is enough for me! He has shown me enough in my past to know that I can wholly trust in Him!