what's your opinion about aliens?
Answers
Explanation:
We don’t know whether there are any aliens or not. But there are so many planets in the universe – some say more planets than all the grains of sand on Earth – that many scientists think it’s worth looking.
To help narrow our search, we often try to figure out what aliens might be like, and therefore what conditions they might require. For example, if we think aliens will be made mostly of carbon, like us, then we should look for planets that have carbon. If we think they will depend on liquid water, we should look for planets with liquid water, some of which we have found.
The problem is that figuring out what aliens will be like isn’t so easy. We have only one example of life – life on Earth – to learn from. To see why this is challenging, imagine we wanted to learn about butterflies.