Great Observatories program

The Great Observatories program is a NASA initiative that launched four advanced space telescopes—Hubble, Chandra, Spitzer, and the James Webb—each designed to observe the universe in different wavelengths of light. This multi-wavelength approach allows scientists to study celestial objects from planets and stars to galaxies and the cosmos’s origins more comprehensively. By operating across the optical, ultraviolet, infrared, and X-ray spectra, these observatories provide a richer understanding of the universe’s structure, formation, and evolution, significantly advancing our knowledge of the cosmos.