"Dust makes this cosmic eye look red."


Let's turn to my favorite little space book, Rees' Our Cosmic Habitat:
When we observe Andromeda, we may wonder if Andromedans are looking back at us, maybe with still bigger telescopes. Perhaps they are. But the remotest galaxies viewed in the Hubble Deep Field could not yet have evolved anything so advanced. We are viewing them at a very primitive stage, before there's been time for many stars to have completed their lives for the stellar furnaces to have forged the atoms needed for complex chemistry. There is very little oxygen, carbon, silicon, and so forth to make even rocky planets, so there is scant chance that life has even started.

Looking into space is looking back in time. What we see has already happened. What we see can not see us, because we are in the future. We alone are the future of all this space, stars, moons, and galaxies. When we see a planet that's habitable, we can only say with certainty that it was habitable. The now exists, but it can only be local. Truly distant nows are not available to us.