Hello! Hopefully I can write an effective critique for you. I'm fairly new at this, so I'm terribly sorry if I seem overly critical or rude, it is not my intention. I believe in bringing every little detail to surface, so that it can help you in the best way possible. First however, I'd like to say that this is an epic and awesome work of art. (One that is making me consider if I rate things too loosely.)
Vision: I gave you a 5 in the category of vision. To me, the image portrays not only a theme of, but also a feeling of solidarity. In other words, it makes me feel small, and I think that is what your objective is. Otherwise, it is fantastically Sci-Fi, and I spent quite a lot of time examining the image in the background.
Originality: I gave you a 4.5 in the category of originality. The only reason I didn't give you a 5 is because of how common these landscape type works are in Sci-Fi. Overall the work is unique, and deserves recognition as such.
Technique: I gave you a 5.0 in the category of technique. It is a well constructed and designed image, and your use of colors, value and location is excellent. The construction in the background is particularly interesting, and well made. I wish I could offer further information here, but I think this is an excellent piece.
Impact: I gave you a 5.0 in the category of Impact. Right from the onset, the feeling of smallness and awe overtook me. It is a beautiful image in its own right, and will certainly leave a lasting impression. The pair of people complete the image, by tying in a human element and applying a scale.
Overall: Overall this is an excellent image, and without being extremely critical, it is hard to find fault. I hope you found my critique useful.