Here's why:
* No matter: A vacuum is defined as a space completely devoid of any matter, including air molecules.
* Light can travel: Light, being an electromagnetic wave, doesn't need a medium to propagate. It can travel through the emptiness of space.
While we might think of space as "empty," it's not entirely so. There are still very faint traces of matter in interstellar and intergalactic space, but it's so thin that it essentially behaves like a vacuum.
Here are some examples of vacuums:
* Outer space: The vast expanse between planets and stars is a near-perfect vacuum.
* Inside a light bulb: The glass bulb of a light bulb is evacuated to create a vacuum, allowing the filament to glow brightly without oxidizing.
* Vacuum chambers: These sealed containers are used in various scientific and industrial applications to create a controlled vacuum for experiments or manufacturing processes.
