So how do astronomers detect something that they can't see?

Astronomers could detect the spot from which the picture had been taken.

True, the astronomers had detected a planet - the one on which they were standing.

Because dark matter cannot be seen, astronomers detected its presence through indirect evidence.

However, in 1992, astronomers detected a peak rate of 45 meteors per hour.

How do astronomers detect that a star has a planet orbiting it?

Astronomers have detected the effects of a giant planet in orbit around a star.

Moments later, astronomers detect hundreds more objects, all heading towards Earth.

Several years ago, astronomers detected the sound waves etched by the photons.

Astronomers have not yet detected any bodies that orbit an exoplanet.