Why use an optical telescope instead of a telescope using any of the other EM waves?

Optical telescopes are used primarily because the visible light spectrum aligns closely with the peak sensitivity of the human eye, allowing for direct observation and interpretation of celestial objects. They also benefit from the Earth's atmosphere, which can better transmit visible light than other wavelengths, enabling clearer images. Additionally, many astronomical phenomena, such as star formation and planetary details, are best studied in optical wavelengths, making these telescopes essential for certain observations.