Very good for a competition entry. The basic gameplay is solid, and worthy of longer development; I especially appreciated the different passengers and their special rules, it is a fit idea. The theming is flavourful. The only superficial issue is that the quick pace of the game would favour making the passenger destinations clearer; with the graphical little planets and the solid-color arrows, and the short time you have to deal with the bombs and whatnot, the player is easily confused by something that could be simple. It would likely be worthwhile to put time-sensitive life and death issues like the bomb clearly on the screen, so the player instantly knows where to go to avoid dying.
To improve upon the concept further, seek a balance between the frenetic action of the space boost and time-limited customers, and the tactical aspects of customer picking and route planning; the game should alternate between moments of leisurely deliberation and bursts of action. For added depth, consider a strategic dimension where new planets (and types of customers) are added gradually and the bus itself is upgraded.