Excerpt from WE IMAGINE (2014)

We Imagine

 

We imagine a large portion of empty space, so far removed from stars and other appreciable masses, that we have before us approximately the conditions required by the fundamental law of Galilei. It is then possible to choose a Galileian reference-body for this part of space (world), relative to which points at rest remain at rest and points in motion continue permanently in uniform rectilinear motion. As reference-body let us imagine a spacious chest resembling a room with an observer inside who is equipped with apparatus. Gravitation naturally does not exist for this observer. He must fasten himself with strings to the floor, otherwise the slightest impact against the floor will cause him to rise slowly towards the ceiling of the room. (Theory of Relativity, Einstein)

Just as Einstein and others could predict the effects of near-zero gravity, we can predict that larger aquatic life lives outside earth.
 
That's right. It may seem like a bold statement, but it must be accurate. Why?
 
Let's analyze the first half of the statement. In 1916, Einstein could predict "weightlessness" in space. Briefly, he could predict that astronauts would float in the ship. Other scientists could do this as well based on classical mechanics. They didn't need to travel into space for physical confirmation.
 
Today, we can predict that larger aquatic life must live in places beyond the earth's atmosphere. We've investigated only eight planets. We've found at least one huge body of saltwater, Europa. Earth holds oceans. Let's ignore temporarily the other bodies that hold saltwater, Enceladus, Ganymede, and Callisto.

The universe holds innumerable stars. If each star holds on average two large bodies of saltwater, the universe must hold countless bodies of saltwater. Let's take one trillion as a minimum estimate of the number of stars. Accordingly, I estimate the universe holds at least two trillion large bodies of saltwater. Of two trillion possibilities, larger aquatic life probably developed in one of these large bodies of saltwater.

Larger aquatic life must live in waters beyond earth.