Merry Gravmas!

Sir Isaac Newton was born on December 25. What the future might be like (found here):

...Xian sighed. "My word. You see – you don’t know anything. Yes, Newton was the messiah who lived two thousand years ago, and came to save us all from irrationality. Today is his birthday."

Li looked impressed. "Say, what do you know! Where did this happen?"

"In a quasi-stable, in a little town called Cambridge, which was somewhere in Britain."

"That’s in Europe, isn’t it?" Li said.

"Oh, so you do know something."

"My friend Shao was in Europe last year," Li went on distantly. "His parents took him on a trip there to see the ruins. He said it was very dirty everywhere, with the streets full of beggars. And you can’t drink the water. It sounds like a strange place for a civilization like ours to have started from."

"Strange things happen…" Xiang thought for a while. "Actually, according to legend, it didn’t really start there."

"What?"

"Gravmas."

"How do you mean."

"Supposedly it was already a holiday that some ancient Western barbarian culture celebrated before then, and we stole it. It was easier to let people carry on with the customs they’d grown used to, you see . . . At least, that’s how the story goes."

"I wonder what the barbarian culture was like," Li mused.

"Nobody’s quite sure," Xiang said. "But from the fragments that have been put together, it seems to have had something to do with worshipping crosses and fishes, eating holly, and building pyramids. It was such a long time ago now that—"

"Look!" Li interrupted, pointing excitedly. Outside the window, a levitation platform was rising into view, bearing several dozen happy-looking, colorfully dressed people with musical instruments. The strains of amplified voices floated in from outside. "Carol singers!" Li exclaimed.

Xiang smiled and spoke a command for the household communications controller to relay his voice to the outside. "Good morning!" it boomed from above the window as the platform came level.

The people on board saw the figures in the window and waved. "Merry Gravmas," a voice replied.

"Merry Gravmas to you," Xiang returned.

"May the Force be proportional to your acceleration."

"Are you going to sing us a carol?" Xiang inquired.

"But of course. Do you have a request?"

"No, I’ll leave it to you."

"Very well."

There was an introductory bar, and then,

"We three laws of orbiting are,
Ruling trajectories local and far.
Collisions billiard,
Particles myriad,
Planet and moon and star.
O-ooo . . ."

Merry Gravmas