Although a rather typical scene of this style, you have managed to make a satisfying scene which evokes not only the aesthetic of the tradition of this sort of artwork, but also a sense of majesty, given by the scenery which so often is the most prominent feature of "terrain and space" combination artworks. But this certainly doesn't take away from your work here: indeed, that this sort of artwork always attempts this must mean you have been quite successful at doing it well, since few can keep this quality aesthetic when it has been attempted so many times.
There is a point for originality insofar as you have fused aspects of your own style in this piece, but particularly laudable is the detail and sense of light and colour, with smooth yet sharp use of scenery elements, such as with the stars and planets, and the general sunrise light casting its glow across the sky and landscape. Those stars, nebulae and planets also have an excellent sense of tone, where although similar colours are used throughout, monotony is avoided successfully. And, of course, the way in which the planets are lit, and the lighting of the nebulae which contours with them provides a good eye-catching quality.
The perspective is also quite good, with the large and well spherised closest apparent planet, along with its embossing, setting a sense of distance with the rest of the other planets in the scene. The nebulae also manages to remain smooth without losing much depth – a successful use of empty space has been used between its whisps in order to preserve the depth, to good effect. There are some things to improve in terms of perspective here though, for instance, the rocket-ships, though providing a nice striking contrast against the backdrop of the sky, seem to contradict the geometry of a planet's atmosphere, unless they aren't as high in the sky as they seem. In other words, some sort of bent vertical climb might seem more indicative of passing through a planet's atmosphere, as a "straight line" up seems to curve as the further one is away from it it becomes. Similarly, although not looking bad, that planet or moon upon a planet at the top left seems to have a flattening effect on perspective, given that there is no indication of distance between them.
Some details could be worked on further also, such as with the very monodetailed surface of the landscape, though it isn't unbearable, and even works quite well, it does seem to pass into the boundaries of artificiality. Some more contrasting details in the nebulae at the top could also emphasise the quality further (thinking of something along the lines of *sirgerg's Pegasus), however it isn't necessary, as it does look quite good as is (but the suggestion is there if you want to try and make it better yet).
Otherwise I must say that the starfield, planetary details and nebulae in general have a splendour and celestial majesty about them which is worthy of note, and to that the overall technique and impact of this piece has shown itself to be quite good. Although not particularly original nor of a unique vision, this piece is still sufficiently well envisioned to have a good overall effect and quality, which suggests the potential to make yet still greater works.