Increasing structural integrity on Phobos, is it possible?

Question

In Warlords, Phobos is comparable to Ellis Island for Mars with its surface being home to many decent sized colonies and space ports (making use of the close proximity of Phobos to Mars) that facilitate migrants, travelers, and citizens, to and from Mars.

One issue though: Phobos is falling apart. From what I can tell Mars is slowly ripping it apart and Phobos itself isn't a solid rock which doesn't help.

The Hegemony has already begun to settle Phobos and would rather try and keep the Moon intact then try and relocate.

Now how would they go about this? The main issues are:

1. Structural integrity of Phobos
2. Martian gravity tearing it apart (I don't know if this can be solved simply by fixing number one)

Note: in my head I was thinking of somehow slowly filling in the cavities between rocks with, well something, and then on the surface having massive (probably hydraulic) pumps keeping it compressed.

Answer 1

Part of the issue is Phobos may be a "rubble pile" asteroid, largely held together by friction, electrostatic attraction and self gravity. Conventional means of construction may not be applicable or even valid (building truss work through the body of the moon will interfere with building colonies or other uses).

Using my favourite methods, I would suggest using thermal energy delivered by mirrors, or the big honking laser around the Sun (used to terraform Ganymede) to sinter the outer surface of the moon. The particles fused together now form a rigid shell, and mining and other activities can take place within without too much difficulty. The amount of heat energy needed will have to be calculated by knowing what material the moon is actually made of, and it is likely that you will be dealing with a very eclectic mixture of rock, carbonaceous material, metals and so on.

The sintered exterior of the moon can be further strengthened by wrapping it in a net made of high quality titanium or some super material which is impervious to the vacuum and ultraviolet radiation environment of space (M5 fibre might be suitable), and actively monitoring the tension in the various strands of the net to ensure uniform tension throughout.

These steps will harden the moon considerably against things like micrometer impacts, spaceship collisions at the docking ports and so on, but cannot be considered "military" hardening. High speed kinetic energy weapons will slice through this quite easily. Hopefully there is some sort of Geneva Convention like rule preventing attacks on civilian habitations.

Answer 2

Tidal force on a planetoid is a "misalignment" of the effect of gravity from another planetoid (as compared to a real estate agent's ideal orientation) - pulling more on the "middle" than on the "edges", squashing the planetoid leading to potential cracking and change in orbital velocity.

Due to Phobos's modest size this proved fairly easy to ameliorate once Terran physicists figured out how gravity propagates through the ether and developed materials and devices which could interact with it:

On Phobos's Mars side there are now several thousand ether mask towers spread around the central 2/3rds of the map as viewed directly from Mars; these are constantly powered to produce an invisible array of gravity umbrellas which lens the the Mars-Phobos mutual gravitation interaction flows away from the center of Phobos and Mars, all but eliminating the tidal stress on the moon as well as the reduction of Phobos's orbital velocity.

Phobos is now not expected to approach the Roche Limit until after Sol turns into a Red Giant and consumes Terra.