A hard sprint would put you into orbit. A good throw leaves Phobos entirely.
Every figure below is tagged with where it came from. Measured means an instrument read it on or at the body; modeled means it was computed and never directly observed.
No world off Earth is habitable — the honest habitable fraction of every surface here is zero. What can be answered is how far each one sits from Earth along the seven axes a habitat has to buy its way out of. Phobos scores 48.7 out of 100, on 100% coverage of the axes. The single worst axis here is pressure (Vacuum); the one that most sets Phobos apart from the other thirteen is water.
Below the Armstrong limit (0.062 bar) body fluids boil at body temperature — the difference between needing a mask and needing a pressure vessel. Above 1 bar the problem inverts into containment, and Venus at 92 bar has never let a lander live two hours.
Water is drinking water, breathing oxygen and rocket propellant in one deposit. A world without it has to import all three forever.
Nobody has ever measured long-term human health at any gravity between 0 and 1 g. Below about 0.1 g, anchoring anything — including yourself — becomes the design driver.
Shielding is mass, and mass is the single most expensive thing to move. Above roughly 1 mSv/day a surface habitat has to be buried.
Never landed on. Fobos-Grunt failed in Earth orbit in 2011; JAXA MMX is due to land and return a sample.
Unprotected survival: Seconds, as in any vacuum.
Possible buried ice inferred from low density, never confirmed. Phobos may be captured asteroid or re-accreted Mars ejecta — the sample return mission MMX is meant to settle it.
The IAU has approved 20 names on Phobos, each drawn from a theme the naming committee chose for this world. Every name in the scene above is one of them, placed at its catalogued coordinates.
Imagery is public-domain NASA/USGS mission data, streamed live from NASA Trek as a plate-carrée tile pyramid and draped on our own sphere — no third-party globe library and no cached copy of anyone else's map.
