OK, my belief is this:
There is an implicate order in the structure of the universe. (See David Boehm's "Wholeness and Implicate Order" about what processes may underlay the randomness of quantum physics.) Note that in my case this does not imply a supra-personal creator. It implies that what ever is generated in the structure of the universe is inherent.
The inherent structure of the universe drives on the one hand to complexity i.e. subatomic particles to simple atoms like hydrogen to larger atoms as the periodic table progresses to molecules to simple organisms to more complex organisms, etc.
The inherent structure on the other hand drives towards increasingly complex consciousness also.
So the answer would be - no, if you mean by not alone that there are other conscious entities in the universe. I see no reason to assume that humans are the only reflective consciousness in the universe or the most advanced one. The faintest stars that we can discern with our technologies are billions and billions of light years away. That is a lot of time and space for consciousness to develop. And this is also assuming that the processes of the universe are to some extent orderly and the earth is not an anomaly.
As for whether there could be other planets like earth. Water is essential to earthly life but the existence of water is not unique to earth. We now know that water forms as ice in star nursery clouds like those in Orion. I can dig up a link if anyone wants to see it. Or you can google "The Mountains of Creation" for neat Nasa pictures. If water made it to earth as ice in comets and other bodies traveling through space, it could go elsewhere also.
So that's my belief with some science to back it up. It makes more sense to me than any separate from its creation Creator being. That is gut feel rather than proof but it combines reason and intuition for me.
Kernos:
'Science' doesn't have beliefs; individual scientists have beliefs which can interfere with their objectivity. This is why one of the fundamental scientific concepts is reproducibility. This is one of the processes that make the scientific method self-correcting.
You are so right there. The number of people who do not understand what science consists of is truly amazing. (At least in the USA).
Blessings, Heartseed