What technique uses images from multiple telescopes to create a single image?

The technique that uses images from multiple telescopes to create a single image is known as interferometry. This method leverages the principle of constructive and destructive interference of light waves, allowing astronomers to attain higher resolution images than could be achieved by individual telescopes working alone. By combining the data collected from multiple observations, interferometry enables the construction of a clearer, more detailed picture of astronomical objects.

Photometry, while related to measuring the brightness of objects, does not involve combining images from multiple telescopes. Spectroscopy focuses on analyzing the light spectrum emitted by objects, which helps identify their composition, temperature, density, and other properties, but it does not primarily involve image formation. Astrometry is concerned with measuring the positions and movements of celestial bodies, which is distinctly different from the imaging process that interferometry facilitates.