Hah, you are probably just as good at the reverse engineering as I am.

Well changing things and looking at the results only gets us so far, because the only piece of data we've located so far is the planet type -- we don't know where anything else is, or if it is even stored.

Searching for pointers elsewhere in the files that point to stuff we already know is not a bad idea though.

I looked at the pointers you spoke of near the end of each planet record. There are two of them for each planet. The seem to be in little-endian format, three bytes each. They appear to point elsewhere in the same table, making what appears to be a doubly-linked list -- the ordering is a bit odd (some pointers don't go where you expect them to), but I suspect that may be because Forth is a stack-based language and it would be easier to process that way.

It seems like the planet data is in reverse order also, just like the orbital position byte (outermost planet is first for a star, and the innermost is last).

I believe the series of blanks could be to hold some state information when that planet is visited by the player, and is not where the actual planet data is stored.

Actually, the hex editing you've done does give us some clues. It doesn't conclusively say, but it does hint what kinds of data we should expect to find. Clearly, some of it is a function of other data. Temperature is related to orbital position and stellar class, Gravity is a function of planet type and size, and so on. What is unclear at this point is whether each of these values are derived purely computationally or whether they have some input, such as a random seed.

One thing I can say with a good degree of certainty is this: since the planets always have the same characteristics when you visit them, there has to be something stored about the planets that we have not yet found. Even if it is just a few seeds that are fed into a random number generator to produce the terrain, atmosphere, gravity, etc, those seeds have to be stored somewhere.

Some other things, like maybe the lithosphere elements are stored also. But I think there has to be another planet table that we are still missing.