The Sun's outer atmosphere is static, with no continuous high-speed flow into space.

The Sun has an atmosphere, and its outer region, the corona, is extraordinarily hot. Mid-twentieth-century models treated it as an atmosphere supported against gravity by gas pressure, carrying heat outward without a persistent fast flow of material.

There were already competing clues and ideas. Comet tails suggested an outward stream of solar particles. In 1958, Eugene Parker worked out how the hot corona itself could expand and accelerate into a continuous wind.

The proposal was controversial. A static atmosphere and a much slower solar breeze remained serious alternatives. Early spacecraft detected escaping particles, but their short observations left room for disagreement. Mariner 2’s sustained measurements on its way to Venus in 1962 established a persistent, rapidly moving stream.

The solar wind is plasma: charged particles carrying magnetic fields. It supplies a moving connection between the Sun and the planets, shaping Earth’s space environment.

This does not mean that the entire corona pours out freely. Magnetic loops can confine plasma in closed regions, while open magnetic regions feed the wind. The wind’s detailed heating and acceleration remain active research questions; its existence no longer does.