He was simply saying that the atmosphere and magnetic shielding generated by the Earth is an incredibly small layer that is completely transparent and delicate, yet, competently separates and protects all known life in the Universe from the dark, cold vacuum of space, which would mean death for all.
Even the light he was able to see permanently leaves the Earth, to never again provide its life-giving characteristic.
I guess. I could tell he was profoundly affected, though. I would probably be like “That’s it? I was expecting more. I don’t suppose I could get my money back…”