Astronomers use different types of telescopes to observe different parts
of the electromagnetic spectrum. This allows astronomers to study
objects in space. Each type of electromagnetic wave can travel through
space at the speed of light. Sometimes astronomers will use two
telescopes on opposites sides of a planet and combine the image from
each telescope. When combined, the two telescopes act like one giant
telescope and have the ability to reveal important details from space. If
astronomers are detecting electromagnetic waves with a wavelength of
109, what type of wave are they detecting?*