The darkness of space and shadows are related concepts but are not exactly the same thing.
The darkness of space is primarily due to the absence of light. Space is vast and mostly empty, and there are very few sources of light compared to the vast distances between celestial objects. In the absence of a nearby light source, such as the Sun or other stars, space appears dark to our eyes. However, it's important to note that even in the darkest areas of space, there is still some background radiation, such as cosmic microwave background radiation, which fills the universe.
On the other hand, shadows are created when an object blocks or obstructs the path of light. When light from a source encounters an opaque or partially opaque object, it cannot pass through that object in certain areas, creating regions of darkness behind the object. These dark areas are known as shadows. Shadows can be observed both in space and on Earth when light is blocked by celestial bodies, spacecraft, or other objects.
Regarding the question of whether the empty void of space has a surface, space itself does not have a solid surface like the ground we walk on. Space is a vacuum, meaning it is devoid of matter in the traditional sense. However, it is not completely devoid of interactions. In space, there are various forms of radiation, particles, and electromagnetic fields that can interact with objects and spacecraft. For example, the solar wind from the Sun and cosmic rays can have interactions with objects in space. Additionally, objects in space can interact gravitationally with each other, leading to the formation of galaxies, stars, and other celestial structures.
So, while space does not have a tangible surface, it does contain various forms of energy, radiation, and particles that can interact with objects within it.