Part 3 — Wildflower Planet

In a dream you are drifting unhurriedly over the surface of a grassy planet thick with thistle and wildflowers. It's like floating in calm water over a colorful coral reef. You are in orbit but your speed is slow as sleepwalk — you have plenty of time to look down at each flower and try to think of its name. Dream-air, which lets you breathe without interfering with motion, also lets you smell the heat in the grass.

The people on this planet have the same custom as the others did of posting radar speed signs. There is one a little way off. "Skimspeed here is 10 dimes. Your speed is ___ dimes." As you approach it registers your speed and numerals flash in the window telling you that your speed is 10 dimes. That is reassuring because it means you will stay in orbit close to the surface.

In our terms a dime is roughly one pace a minute (this is the old Roman two-step pace), so your speed here is ten paces a minute and it would take you ten minutes to travel the length of a city block. Slow, but the sun is bright and there is plenty to look at; so you don't need to feel impatient — idle drifting is fine. Other people are coasting along in other directions; sometimes paths cross but you rarely collide. Those in ground-level orbits like yours are all going the same ten-dime speed as you — the skimspeed comes with the planet — so even when you do collide it doesn't hurt. Everything's in slow motion — you even have time for an exchange of courtesies.

There's a large unresponsive billboard which declares:

Skimspeed here is 10 dimes.
Square skimspeed is 100 square dimes.
Rumpus on this planet is 10 000 quartic dimes.
This planet weighs ten thousand tons.

That is the force it would weigh in its own surface gravity — if a copy could somehow be compressed to manageable dimensions and placed on scales at the planet's surface. A planet's weight is what it thinks it weighs. We already met the proportionality between rumpus and weight. A quartic dime corresponds to a ton of planet weight. There is a universal ratio called G and in these terms G equals dime⁴/ton.