Here's why:
* Atmosphere as a filter: Our atmosphere acts like a filter, allowing some wavelengths of light to pass through while absorbing others.
* Visible light window: Fortunately, the atmosphere is relatively transparent to visible light, the range of wavelengths our eyes can see. This means that light from stars and other celestial objects can reach Earth's surface.
* Telescopes capture the light: Telescopes are designed to gather this visible light and focus it, creating images of distant objects.
However, the atmosphere also poses some challenges for telescopes:
* Atmospheric distortion: Turbulence in the atmosphere can cause light to bend and scatter, blurring images. This is why astronomers often build telescopes on mountaintops or in space, where the atmosphere is thinner and less turbulent.
* Light pollution: Artificial light from cities can interfere with astronomical observations, especially in the visible spectrum.
Despite these challenges, the transparency of the atmosphere is essential for ground-based astronomy.
