Cosmic rays
Rayos cósmicos
- Date
- 1912 · confidence high
- Place
- Vienna, Austria (balloon flight to Bad Saarow)
- Credited to
- Victor Hess
- People
- 👤 Victor Franz Hess1883–1964
- Field
- Cosmos & Earth
What was discovered
On balloon flights up to 5,300 m Hess measures that the ionisation of the air increases with altitude: a penetrating radiation arrives from space. It opens particle physics before accelerators and high-energy astrophysics.
Domenico Pacini had measured a decrease underwater at sea in 1911; Millikan coined the term 'cosmic rays' in 1925.
What it led to
- Discovery of the positron, the muon, the pion and strange particles
- High-energy astrophysics
- Study of the magnetosphere and the solar wind
- Atmospheric showers and giant detectors (Auger, IceCube)
Built on
- Natural radioactivity1896
- Wulf's electroscope
Made possible
- The positron: discovery of antimatter1932
- Lemaître–Vallarta theory of the cosmic-ray latitude effect1933
- Yukawa's meson theory and the discovery of the muon1935-1937
- Aragats cosmic-ray station1943
- Radiocarbon dating applied to archaeology1949
- High-altitude particle detectors
- Carbon-14 dating (produced by cosmic rays)