What type of waves have NOT yet been directly detected by astronomers?
A) sound waves
B) gravitational waves
C) X-ray waves
D) gamma-ray waves
E) pressure waves

Question

Quizplus · Accepted Answer

Sound waves cannot travel through the vacuum of space, X-ray and gamma-ray waves have been detected by telescopes, and pressure waves are a type of sound wave. However, gravitational waves have only been indirectly detected through their effects on other objects, such as the distortion of spacetime. Direct detection of gravitational waves was only achieved in 2015 with the Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors.

What Type of Waves Have NOT Yet Been Directly Detected