Space Clouds/Analysis

In the real world, this does not actually happen. Simply put, it would quickly disperse due to intermolecular collisions and thin out into the interstellar medium. Or if it did have sufficient mass or was being compressed by, say, gravity or the shockwave from a nearby super nova, it would collapse into a star.

Now there are clouds of a sort in space (nebulae), but these are objects light-years across, with enough mass in them that gravity can keep them together, and their density is far below even industrial-grade vacuums. In short, if you flew your rocket ship up to, say, the Orion Nebula, it would pretty much look like nothing was there. The density of the gases in a nebula is about 1000 particles per cubic centimeter. The air you breathe just walking around on Earth is around 2.5x1019 particles per cubic centimeter, or about 250-million-billion times denser. The nebula's density may be 1000 times the density of the interstellar medium, but it's still a near perfect vacuum.

To add to the confusion, some of the most famous pictures taken of outer-space phenomena are in false-color -- to help illustrate some aspect of it, such as ultraviolet radiation. This information is not commonly provided in images released to the public, and "true color" pictures of these stellar phenomena are not as easy to find, which means artists are more likely to use the wrong images as a basis for what they look like to human eyes.