 Why doesn't the Earth shoot the spaceship out of the sky?
A gentle fancy for the Christmas Season—an oft-told tale with a wistful twistful of Something that left the Earth with a wing and a prayer. 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. Machines compiled dictionaries and grammars and began translating the major languages. 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. "I can guess," said Ethaniel, who had spoken first. "It's not what they've done," said Bal, the second alien. "The big bomb can destroy them. "I may remind you that in two months twenty-nine days we're due in Willafours," said Bal. "Without looking at the charts I can tell you we still have more than a hundred light-years to go." "A week," said Ethaniel. 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." "We'll just have to forget there ever was such a planet as Earth." Except for the one thing they lack, and that's quite odd, they seem exactly like us. "It is. "There is. "In a week we can't negate their entire history. "You can't tell," said Ethaniel. "And then what? "And when we get to Willafours we'll be busy. There's nothing in this region of space our people want," said Ethaniel. "And how long can Earth last? We're not committing ourselves by looking." 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. "Well, we knew they had the big bomb. Atmospheric analysis showed that as far away as we were." "We also knew they could deliver the big bomb, presumably by some sort of aircraft."
 The combination of the Christmas holiday, aliens that look like angels, and what looks to be the star of Bethlehem, has convinced the people of Earth that Bal and Ethaniel are friends and not foes.
 The Earth does not have weapons that are capable of going as high as the spaceship. Nor are their weapons capable of penetrating the spaceship's hull.  Bal and Ethaniel are using the spaceship to broadcast a message of peace in all the languages of the world.  The combination of the Christmas holiday, aliens that look like angels, and what looks to be the star of Bethlehem, has convinced the people of Earth that Bal and Ethaniel are friends and not foes.  The spaceship is lit up as brightly as a star. The light is bright enough to convince the humans that firing upon it would be futile.