An advanced alien civilization develops the technology allowing interstellar travel and comes to Earth. Now, let’s be clear on what that all entails – Firstly, space isn’t just a simple vacuum where you can travel from one expanse to another without any real danger. There’s plenty of danger out there from Gamma Ray Pulses, micro black-holes, and even the smallest specks of dirt that could utterly destroy any unprotected vessel simply from the velocities involved with both the ship and object.

Secondly, light from our nearest star takes a bit over four years to reach us here on Earth. Light from Bernard’s Star takes almost 6 years to reach us. Vega, one of the brightest stars in the sky takes 25 years to reach at the speed of light. With that in mind, in order to make interstellar travel practical you have to have technology able to either travel significantly faster than the speed of light or have some way of accommodating the crew for such a long journey (ie: cryogenics or time-manipulation).

So what we are left with is an alien culture so technologically advanced that not only are they able to traverse the distances of interstellar space, but can do so safely while avoiding all the hazards found naturally occupying in the galaxy.

And even though they are capable of all those incredible feats and possibly more…

…when they get here they crash in the empty Nevada desert.