Telescopes on the ground and in space

A telescope's light-gathering power depends on the area of its main mirror or lens, which grows with the square of its diameter: a 10-meter telescope collects 25 times as much light as a 2-meter one, letting it see much fainter objects. Different telescopes see different parts of the spectrum, each with strengths and limits. Large ground-based optical telescopes are more affordable and easier to upgrade than space telescopes, but Earth's atmosphere blurs and absorbs some light, which is why they sit on high, dry mountains and often use adaptive optics. Infrared telescopes see through dust and detect cool objects, but water vapor absorbs much infrared light, so many must be at high altitude or in space. Radio telescopes work day or night and through clouds, and several dishes can be linked into arrays for sharper images. Gravitational-wave detectors like LIGO sense ripples in space-time from events such as merging black holes, first detected in 2015. Space telescopes, like Hubble, the infrared James Webb Space Telescope, and the X-ray Chandra observatory, avoid atmospheric blurring and can observe wavelengths, such as X-rays, most ultraviolet, and much of the infrared, that the atmosphere blocks, but they are expensive and hard or impossible to repair.

This explanation is AI-generated and can occasionally be wrong. 🚩 Report