Researched
X-Ray Astronomy
On 19 June 1962 a rocket-borne detector found the first X-ray source outside the Solar System, Scorpius X-1; the Uhuru satellite (1970) then catalogued hundreds of sources, including black-hole candidates.
Open in the interactive tree →The atmosphere absorbs X-rays, so the sky can only be seen from above it; V-2 rockets caught solar X-rays in 1948-49. An Aerobee 150 rocket flown by Giacconi, Gursky, Paolini and Rossi found Scorpius X-1 in June 1962, a source about 10,000 times brighter in X-rays than in visible light. Uhuru, launched on 12 December 1970 from Kenya, catalogued 339 sources, discovered pulsing X-ray binaries and helped identify Cygnus X-1, the first strong black-hole candidate. Giacconi shared the 2002 Nobel Prize in Physics for these discoveries.
Prerequisites
- X-Rays1895X-rays had been known and measured since 1895.
- V-2 Rocket (First Rocket in Space)1942Rockets lifted detectors above the atmosphere, which absorbs X-rays.
- First Satellite (Sputnik)1957Uhuru, the first X-ray satellite, scanned the whole sky from orbit.
Unlocks
- Black Holes (Cygnus X-1)1971-72Cygnus X-1 was found as an X-ray source before it was linked to a compact star.