The year length is the most important thing? What about planets with extremely long days? Or no days at all? He sends an image of a tidally-locked planet, then of a gas giant moon. Or moons of gas giants that have a correct year but orbit the gas planet much faster?

Day length is important but not to within the same factor - we're capable of seasoning properly even with lots of artificial light around or on a nocturnal schedule - but tidal locking would not work. The moon it'll depend, I'd need to have a working model of the exact astronomy involved.

Not many planets are tidally locked but that rules out a few. I think the moon in question is not ideal in other ways.

Second most important, a molten core. Third most important, existence of water. How important is temperature, magnetic field, axial tilt, presence of oxygen, gravity? Would severe seismic or volcanic activity be prohibitive?

The green gives ranges for all of these things!

And the dragon eagerly talks about possible terraforming techniques with him! He hasn't studied terraforming specifically but he's good at chemistry and math, and a pretty quick study. The telepathy helps with complex ideas.

Eventually, I know which planets I will tell you about. None are very like here but several are reasonably similar!

That's great! I'd love to hear all about them and we can start projects to figure out what to do with them if we ever get there.

I have to get my survey computer to send valid data to the pocket everything - I can't wait to take one apart under a microscope I have single purpose computers only - and then you can have maps and sample analyses and all the rest. I can summarize them now as well?

Will your survey data be in a format the pocket everything can read, or raw binary...?

I can send it in raw binary as soon as I build a radio transmitter and understand the file transfer protocol. I was hoping to do something slightly more elegant, that seems ugly.

And it'd be hard to decode! I'm glad you can improve on that. I would like the summaries too.

Here are the summaries. The most promising are:

One with a year length that's short, just barely in the 'plausibly seasonable' range, decent geothermal potential, a thick nitrogen and carbon dioxide atmosphere, and very very salty liquid water occasionally present on the surface.

One with a year length a quarter of a season longer than Amenta's, excellent geothermal potential, with no water but a lot of ice asteroids present in the star system.

One with barely any atmosphere and no molten core, but perfectly nice ice caps and a year length almost exactly the same as Amenta's.

Of course, I have looked closely at only a tiny slice of the stars. I have journeyed off and on for only two years. There are almost certainly better candidates out there, yet to be found.

The green's relaying all this to a yellow assistant, who takes detailed notes. These are much better than anything in our own system!

Yes, when there are more random options something good is more likely to turn up. Even in the most boring river in the world, there are one or two pebbles pretty enough to be treasure among their million siblings.

Blue are the wise ones. Green are the clever ones. What is yellow for?

Yellow is for conscientiousness, if that's how you're categorizing them.

I only got here yesterday and have not received a full explanation of castes yet! I am well aware that fast simple summaries of a complicated subject are often flawed. Draak have castes of a sort, but I think it's fairly different.

Should I be calling Amseli back into the loop?

If she is better at explaining castes, perhaps. But first, what is your job name and what does it mean? Job names are good.

My job name is Satkafintesh. It means a clear view of a distant place.

I like it. I wonder if you are more like me than Amseli is? ...Thank you for speaking with me.

He turns his head and changes the target of the song.

Amseli. Hello again. Satkafintesh says you will be better at explaining castes. I have observed some of it, but I would like a more direct explanation.

Of course! Is there any specific question you have or should I just summarize?

He was disconcerted by me characterizing blues as the wise ones and greens as the clever ones. (Amusement) A summary from your perspective, I think.

Well, a caste is a little like a supercategory of job. It's hereditary - my children are blue like me, for example. Blue own and manage land, handle the justice system, and represent our people in the government. Greens study and practice the arts, the humanities, and the sciences. Yellows do administrative tasks to keep systems running, a definition which lately includes software. Oranges look after other people - children, the sick, the old, the lonely. Greys protect - soldiers, police - and are also dancers and athletes, when there's nothing to fight. Purples do - everything else. Manufacture, maintenance, agriculture, service work, transport - there are a lot of purples. The things that none of us can come into tolerable contact with are sequestered into the last caste, reds, who are less sensitive to it, and they dispose of the bodies of the dead, handle wastewater when our automatic systems for it fail, and remove garbage from where people live and work.

We have something not very much like that. Almost... Subspecies. All Draak can do all things Draak do if they have the skill and desire to.

Sapphire Caste like me are at home in the water. We can breathe in the water. Ruby Caste are at home underground. They are capable of fast tunneling. Emerald Caste are at home in forests and grasslands, the best hunters and flyers. Onyx Caste are nocturnal and secretive. Diamond Caste are extinct. Intercaste hatchlings are always a specific caste and do not have, for example, some Sapphire traits and some Emerald ones - more often the mother's than the father's.

Those do sound more like subspecies than like castes. We account for caste matrilineally, in cases of crossings, since the traits blend but we don't have a way for someone to be legally two castes; but some countries do it patrilineally, which has more opportunity for mistakes in who the lineal parent is but in the normal case is just as predictive. But most children's parents are the same caste.

Your caste system seems like a social construct to me. Like countries, or trading circles. Of course, that does not make it any less real. Just because you can't touch or see something doesn't make it not real.