Caption: A phase diagram of water on a semi-log plot.
Features:
As one goes to the right, one passes through the three phases: ice, liquid water, water vapor.
This conclusion is true for all materials, NOT just water.
The upshot is that a distinct liquid phase is a rather delicate phase of matter and, in fact, in many astrophysical environments the pressure is too low or too high for it, and consequently many astrophysicists NEVER think of the liquid phase at all for any substance or material.
However, life as we know it requires liquid water, and so astrobiologists spend all their time thinking of liquid water.