The possibility that life may exist elsewhere in the universe has captivated the minds of many. The fact that we have yet to find any smoking gun evidence of alien life has led to a lot of theories about where and under what circumstances we might find them if they’re out there, and one theory suggests that there might be another Earth right here in our own solar system, complete with its own life and civilization, but it’s just somewhere we can’t see it.
The idea goes like this: we know that the Earth exists and has life on it. We also know that Earth’s specific location in the solar system was important because it’s just the right distance from the sun to be the right temperature and have liquid water, and we have a giant neighbor named Jupiter that attracts and absorbs a lot of the dangerous stuff that might otherwise make it into the inner solar system and hit Earth.
Since the conditions are so perfect for life to arise in our neighborhood, the Counter Earth Theory suggests that another Earth with life on it might exist elsewhere on Earth’s own orbit. Imagine a planet the same size, same distance from the sun, with all the same elements in the same proportion, following the same orbit as the Earth, but all the way on the other side of the sun, a full 180 degrees from our position.
The theory suggests that, if such a planet existed, the conditions for life to arise would all be there, but since the sun would block our view of it, we would have no idea this planet existed. There could be another entire alien civilization literally around the corner from us, but our relative positions would prevent either planet from being able to discover or observe the other.
Obviously, we now have the means to know that no such planet exists. Satellites have travelled far enough to have had a clear view of where this planet would be and been able to identify it, and we’ve seen no visual evidence that anything is there. Nonetheless, science has provided us with other ways of confirming there is no Counter Earth even without visual evidence (or a lack of it).
For one, Earth’s orbit is elliptical, not perfectly round, so there would have been periods of the year when we could have seen a planet following our orbit from here without the sun obstructing our view. We also would have been able to detect the effects of a Counter Earth’s gravity on the objects around it, but no such effects exist.
While intriguing, we have to admit that the Counter Earth Theory doesn’t hold up until scientific scrutiny. And so the search continues.