Shuttle White Grey — 2 museum-grade prints in this palette. Compton GRO was the second of NASA's four Great Observatories — after Hubble and before Chandra, Spitzer, and the multi-wavelength program that transformed 1990s astrophysics. BATSE's burst catalog established that gamma-ray bursts were cosmological, not local solar-system phenomena, setting the stage for Swift and Fermi decades later. Chandra is named for Subrahmanyan Chandrasekhar, whose limit defines the maximum mass of a stable white dwarf — a foundation of stellar death physics. Riccardo Giacconi's Nobel-winning X-ray discoveries made the observatory's science case irresistible.