It's a material world and you have a material body and are relegated to existence here only because of it. You aren't walking out. Or flying out. You live here, you work and travel here, you die here. No space. On death since you depart from your material body you will have 3 days for your spirit to roam the earth to anyplace you delight. And then a chance to ascend the ladder through the aerial toll houses. If you have lived a life saintly enough you are allowed to pass them upward into the greater heavenly realms. Then perhaps you will have your adventure in the vastness of creation that you call space. From the teachings of Seraphim Rose and other holy fathers it is understood that many of us are caught in the lower realms and aren't allowed to pass. This is why we pray for the dead. An act of love. Good morning.
Genesis 3:19
In the sweat of thy face shalt thou eat bread, till thou return unto the ground; for out of it wast thou taken: for dust thou art, and unto dust shalt thou return.