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Hubble Space Telescope

The Hubble Space Telescope's five science instruments — its cameras, spectrographs, and fine guidance sensors — work either together or individually to bring us stunning images from the farthest reaches of space. Each instrument was designed to observe the universe in a unique way.

The Advanced Camera for Surveys, which was installed in March 2002, represents the third generation of science instruments flown aboard the Hubble Space Telescope. Among other tasks, the new camera will be used to observe weather on other planets in our solar system, conduct new surveys of the universe, and study the nature and distribution of galaxies. 

The Wide Field and Planetary Camera is the "workhorse" instrument behind nearly all of the most famous Hubble pictures. As Hubble's main camera, it is used to observe just about everything. 

The Near Infrared Camera and Multi-Object Spectrometer is Hubble's heat sensor. Its sensitivity to infrared light makes it useful for observing objects obscured by interstellar gas and dust (such as stellar birthsites and planetary atmospheres) and for peering into deepest space. 

The Space Telescope Imaging Spectrograph is a versatile instrument that can act somewhat like a prism, separating light from the cosmos into its component colors.

The Fine Guidance Sensors are targeting devices that lock onto "guide stars" and measure their positions relative to the object being viewed. Adjustments based on these precise readings keep Hubble pointed in the right direction. The sensors also are used to perform celestial measurements. 

Removed in 2002: The Faint Object Camera was Hubble's telephoto lens, recording detailed images over a small field of view. This instrument was replaced by the Advanced Camera for Surveys in early 2002.

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