what do these circles mean?

[Gregorovitch55]

I had one around one system and it disappeared. Now two more have appeared.

[Balkor Wolf]

Theyre to do with fleet posture I believe. One of the buttons on top of the menu you get in the bottom right of the screen (Above the minimap) will turn them on and off.

[garfield666]

isn't that long range scanners' range?

[Balkor Wolf]

Nah the long range scanners have a light blue/whitish glow around the point of the scanner. Those solid blue ones are something different.

[Fleshbits]

Which circle?

The solid line around a star means there is a colony.
The colored background is scanner range.

[Gregorovitch55]

Yes, they are fleet postures, I can turn them off with that button, now I've found it.

What I don't understand is why. I haven't set any postures, so it must be to do with the AI, and there are no fleets in either of these systems. One of them has a few escorts running around and the other has no military ships at all in it.

[Balkor Wolf]

I think it is possibly to do with a fleet on where their homebase might be set as. Possibly. I've never really looked into it that much since the option is only ever on if I put it on by accident =P

[Darkspire]

I had one around one system and it disappeared. Now two more have appeared.

The blue circles around the system are Fleet Defense Posture ranges. If you select the fleet that is based in that system that is based at a colony and change the range from local to system to sector you will see the circles increase in size.

The yellow circles are either colonies or research sites worth scouting (is there one for tourism? cant remember), all three / four can be turned on and off using the switches on top of the map in the SE corner of the UI.

Long range scanners can also be toggled from that row of switches, you have none on at present, when they are on it is shown as a circle, same as Fleet Defense Posture but grey, that too can increase in size by increasing the tech in the HiTech tab.

Darkspire

[necaradan666]

I'd guess it's the 16th Strike Force as you can see it's set to defend, and those overlays would be where the fleet is based, doesn't have to be a colony, you can set them to mining stations and such too.. Home Fleet is set to defend to but it looks like it's set to a smaller range than those circles would indicate, it possibly doesn't have a home base set

If they don't have a home base you don't see the blue circles, if they were on attack posture like the other fleets you wouldn't see them either. If they were on attack posture and you gave them an attack target you'd see a red circle around the target instead.

Fleet Postures are very useful.

[Aeson]

Yes, they are fleet postures, I can turn them off with that button, now I've found it.

What I don't understand is why. I haven't set any postures, so it must be to do with the AI, and there are no fleets in either of these systems. One of them has a few escorts running around and the other has no military ships at all in it.

If the AI is given control of fleet management, then the AI will assign home bases and postures as it sees fit. At least one fleet has been assigned a home base in Tafuueri, and at least one more has been assigned a home base in Dhayu, and at least one fleet based in each system has been assigned to defensive posture with an engagement radius of "nearby systems." Fleets which are based in a system will not necessarily remain in that systems; possible reasons for their nonpresence are refuel/repair/retrofit orders that take them out of their assigned area of operations, you the player issuing orders to the fleet that send them elsewhere without changing the home base and fleet posture, recent assignment to that duty station which hasn't allowed the fleet enough time to arrive on station yet, the ships of the fleet(s) assigned to that duty station have not yet been commissioned (the ships are still under construction), or the fleet may be responding to a threat in another system covered by their area of operations (shown by the blue circle), and there may be one or two other reasons that I'm forgetting at the moment. In your case, it does not appear that either fleet is within its assigned area of operations.

If you want to determine which of your fleets have been assigned to these areas, you should open the Fleets menu (the menu button that looks like three ships at the top of the screen, not the list you have open in the screenshot) and look for fleets with a home base in the system at the center of the blue circle (in your case, either Dhayu or Tafuueri; the computer typically assigns colonies as fleet home bases, so you may want to check the names of the colonies in the two systems before searching your fleets list). Once you've found fleets assigned a home base within that system, you can check their postures and engagement ranges by selecting the fleet from within the fleets screen, and this will allow you to tell if the fleet is in aggressive (sword icon) or defensive (shield icon) stance, and the engagement range is indicated by another icon in the same area, which looks like a yellow dot that should have a dashed ring around it (since your engagement range setting is 'nearby systems;' the ring will also be there for system-wide and sector-wide engagement range but the radius of the ring will be different, while target-only lacks a ring and engage-anywhere has a ring of outward-pointing arrows). Based on the fleet activities listed in the screenshot, I would guess that the two fleets that are creating these blue circles are the Home Fleet and the 16th Strike Force, as both fleets are in defensive posture whereas none of the other fleets are. Since the 16th is automated, it should eventually turn up in whichever of the two systems contains its home base, while the Home Fleet will remain wherever it currently sits unless something gives it orders.