Regions and Features of the Sun

Regions and Features of the Sun

The main regions of the Sun include its interior, surface (photosphere), and atmosphere.
Credit: SOHO (ESA & NASA)

Planets such as Earth have regions with specific traits - places like continents, oceans, and polar ice caps. The Sun also has regions, but of a very different nature. Many temporary features and phenomena, somewhat akin to weather patterns on Earth, also crop up on the Sun from time to time. Let's take a look at the regions and features of the Sun!

The interior of the Sun is divided into three main regions. At the center is the core, where energy is produced by nuclear fusion at incredible temperatures. The core is surrounded by the radiative zone, which in turn is enclosed within the convective zone. The visible "surface" of the Sun, called the photosphere, sits atop the interior layers. The Sun also has an atmosphere, with a lower region called the chromosphere and an upper section known as the corona.

Numerous features, with lifetimes of seconds to months, appear on the Sun's surface and in the solar atmosphere. Sunspots are dark blotches on the Sun's surface which reveal the presence of powerful magnetic disturbances. The disturbed, magnetically active regions around sunspots often generate solar flares and coronal mass ejections (CME), two types of immense explosions. Solar prominences, filaments, and coronal loops are structures formed from plasma suspended by magnetic fields in the Sun's atmosphere. Voids called coronal holes sometimes appear in the solar atmosphere, allowing fast streams of solar wind to flow freely outward into space.

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