 How did the climate affect the humans' perception of the aliens?
Earth was so far away that it wasn't visible. But this vast distance did not mean that isolation could endure forever. Instruments within the ship intercepted radio broadcasts and, within the hour, early TV signals. The history of the planet was tabulated as facts became available. The course of the ship changed slightly; it was not much out of the way to swing nearer Earth. "We've got to make or break," said the first alien. "It's not what they've done," said Bal, the second alien. They've had two world wars in one generation and that the third and final one is coming up you can't help feeling in everything they do." "The wrong diplomatic move, or a trigger-happy soldier could set it off. A meteor shower could pass over and their clumsy instruments could interpret it as an all-out enemy attack." "In a week we can't negate their entire history. There's nothing in this region of space our people want," said Ethaniel. "And how long can Earth last? They went much closer to Earth, not intending to commit themselves. For a day they circled the planet, avoiding radar detection, which for them was not difficult, testing, and sampling. Atmospheric analysis showed that as far away as we were." "What's worse is that I now find they also have missiles, range one thousand miles and upward. They either have or are near a primitive form of space travel."
 The cold pushed the aliens to fly a bit, exposing their wings.
 The cold pushed the aliens to fly a bit, exposing their wings.  The aliens seemed extra out of place in the cold.  The cold was what allowed their ships to glow and look powerful.  The cold made it harder for the aliens to travel on the surface.