Interstellar gases in space are typically not in a solid state, even though they are extremely cold due to the low temperatures of space. The reason for this is that interstellar gases are composed mainly of individual atoms, molecules, or small clusters of molecules, which primarily exist in the gas phase rather than as solid particles.
In space, the temperatures can approach absolute zero (0 Kelvin or -273.15 degrees Celsius), especially in regions far from stars or other heat sources. At such low temperatures, most substances on Earth would freeze and become solid. However, interstellar gases have such low densities that they remain as gases even at these low temperatures.
The low densities in interstellar space mean that the particles are spread out over vast distances, with large empty regions between them. As a result, intermolecular forces and collisions between gas particles are rare and insufficient to bring them close enough together to form a solid. The gas particles in space, such as hydrogen, helium, and other elements or molecules, exist as individual entities moving freely in space.
However, it's worth noting that under certain conditions, such as in denser regions of interstellar clouds or during the collapse of molecular clouds, interstellar gases can condense and form dust particles or ice grains. These particles can eventually contribute to the formation of stars and planets. But as a whole, interstellar gases in the vast majority of space remain in a gaseous state despite the extreme cold.