space telescope
Earth's atmosphere is a mixed blessing for stargazers: it keeps us alive but smears starlight and blocks whole bands of the spectrum. The cure is to leave it behind entirely. A space telescope is an observatory placed in orbit or out in deep space, above the air, where the view is steady and the full electromagnetic spectrum lies open.
Going to space buys two great advantages. First, with no atmosphere there is no seeing, so a space telescope can work right at its diffraction limit, delivering rock-steady images night and day. Second, the atmosphere is opaque to most of the spectrum — it absorbs nearly all ultraviolet, X-ray, gamma-ray, and much infrared light — so observatories for those wavelengths must fly above it. The Hubble Space Telescope works mainly in visible and ultraviolet light from low Earth orbit; the James Webb Space Telescope sees the infrared from a deep-space point 1.5 million km away, shaded from the Sun; X-ray observatories like Chandra catch radiation that would never reach the ground.
The price is steep. A space telescope cannot be casually serviced, must survive launch and the harsh environment of space, and costs far more than a ground telescope of similar aperture. So astronomers reserve space for what the ground simply cannot do — the wavelengths the air blocks, and the diffraction-limited sharpness and stability that even adaptive optics cannot fully match — while ever-larger telescopes on the ground handle the rest.
The James Webb Space Telescope orbits a balance point 1.5 million km from Earth — four times farther than the Moon — kept cold and dark behind a tennis-court-sized sunshield so it can sense faint infrared light.
Above the air, the whole spectrum opens up.
Being in space does not make a telescope see 'closer' or bigger — it removes the atmosphere's blur and lets through blocked wavelengths. A space telescope still obeys the same aperture and diffraction limits as one on the ground.