The ability of light from an exploding star, or supernova, to reach us without being significantly absorbed or scattered by dust and gases depends on various factors, including the distance between the supernova and our location, the properties of the intervening medium, and the wavelength of the light.
In general, when a supernova occurs, it releases an enormous amount of energy, including a burst of intense radiation across the electromagnetic spectrum. This radiation initially travels at the speed of light in a vacuum, which is approximately 299,792 kilometers per second (186,282 miles per second). However, as it encounters interstellar dust and gases, some of the light can be absorbed, scattered, or otherwise affected.
The extent to which the light is absorbed or scattered depends on the density and composition of the intervening material. Dust and gas can absorb or scatter certain wavelengths of light more than others. For example, shorter wavelengths like ultraviolet and blue light are more easily scattered by dust particles, while longer wavelengths like red and infrared light can pass through more easily.
If the supernova is relatively close to us and there is minimal intervening material, the chances of the light reaching us without significant absorption or scattering are higher. However, if the supernova is located at a great distance or there is a substantial amount of dust and gas between us and the event, the light may be attenuated or scattered to the point where it becomes difficult to detect or observe.
In some cases, the interaction between the supernova's radiation and the surrounding dust and gas can actually lead to interesting phenomena. The scattered light can produce beautiful astronomical phenomena like light echoes or reflection nebulae, which provide indirect evidence of the supernova event.
To summarize, the ability of light from a supernova to reach us without being absorbed by dust and gases depends on several factors, and the actual observation and detection of the light can be influenced by the distance to the supernova, the properties of the intervening medium, and the wavelength of the light itself.