In the past two years quite a few metallic objects have been observed leaving the dual planet system third from the Sun, such as that pictured here:
As is well known, the smaller of the dual planet system is completely solid and so could not support life. However, the larger of the pair does have 2/3 of its surface covered in liquid, and some scientists have supposed that simple life forms may be feasible there.
The objects observed leaving that system are inorganic, but they seem to be self-propelled and on specific trajectories to other solar-system objects. One even apparently orbited our host planet, then seemingly deliberately destroyed itself in the host planet's atmosphere. This leads to some scientists to draw conclusions:
- These objects are intelligent, as they seem to navigate the planets.
- These objects are immortal on their own world, as they seem to not fear the certain death of entering our host world's atmosphere.
- These objects may be a form of inorganic life.
Based on the above, how likely is it that a life form, organic or inorganic, might live on an actual planet as opposed to on a moon as we do? Might such an environment actually favor the non-organic beings that we have been observing? Might they really be immortal? If so, why have they only recently begun to leave their planet?
Additionally, it seems that spaceflight is achievable for us as well if we can find a place on our own home moon that has no water. At least one object has been observed to leave that world not from the liquid part, but just a few hundred meters away on the dry part. This might mean that one could leave a world by simply crawling out of the liquid and pushing on the planet. What other factors might complicate this? Could we do something similar someday?
Edit: In fact, I am asking the question from the point of view of intelligent beings in Europa's hypothetical ocean. I present the question as how they might perceive us. Our Earth-Moon system would appear to them as a binary planet, and the idea that life could develop on a planet, as opposed to a moon, would be strange for them. They might also suspect that the probes leaving Earth are the life forms on this planet. Of course, any being which evolved on Europa may suspect that life could only exist in an ocean.