The cosmic microwave background
Two engineers find a hiss they cannot remove, and it is the afterglow of the Big Bang.
- When
- —
- Duration
- 1 years
- Known to
- ± 1 year
- Era
- Contemporary, Holocene
Penzias and Wilson detect uniform microwave noise from every direction in 1964 while calibrating a horn antenna, and eliminate every source they can think of including pigeon droppings. A team at Princeton was preparing to search for exactly this. The radiation is the light released when the universe became transparent, and its discovery settles the argument between the Big Bang and steady state models decisively.