Sound cannot travel in space at all. Sound is a mechanical wave that travels through a medium, such as air or water. In space, there is no medium for sound waves to travel through, so they cannot exist.

However, there are other types of waves that can travel through space, such as light and radio waves. These waves are not mechanical waves, and they do not require a medium to travel through.

So, while sound cannot travel in space, other types of waves can. This is why we can see stars and planets in space, even though we cannot hear them.