Asteroid Fields Growing?

As a check I am revisiting my asteroid fields to check that I got the composition right when I first visited.

On a couple of occasions now I have been to old asteroid fields and found very small asteroids. This seems to indicate that new asteroids are forming in an existing asteroid field.

The fields concerned only contain 'junk' asteroids: Siderolite in one and Urelite in the other. So, it is unlikely that these fields have been visited by another player.

I have not visited these fields myself for three or four years. So, is it possible that new 'roids can spawn without old ones being harvested?

Not all rocks spawn when we discover a field. Some may be far enough away to spawn on the first fly through, so they spawn later. This is why I try to fly all the way through a field when I find good stuff. Better chance that all will spawn the first time through.

Last roid reset was only junk roids, if you go to fields that hasnt been visited since before that, new roids will spawn between the old not junk roids. If thats the case you should not find any kam, sid or chrondites that are grown, but grown of the more valuable roids and newly spawned any type of roid the field consists of.

A few fields did seem to change which roids a field consist of during the last reset, thats a bit confusing, but fortunately very rare.
Urelite is not considered junk in this regard

Thanks guys. That seems to be what I found.