Anatomy of the Sun

Study Notes

The Sun is composed of many layers: Core, Radiative zone, Convective zone, Photosphere, Corona, and Solar Wind.
The core is the hottest part of the sun, where energy is created through nuclear fusion.
The radiative zone is where energy is transported outward through photons.
The convective zone is where energy is transported outward through convection.
The photosphere is the "visible surface" of the sun, where most of the light we see comes from.
The corona is the outermost layer of the sun's atmosphere, which is extremely hot (millions of Kelvin) and can only be seen during solar eclipses.
The Solar Wind is a stream of charged particles ejected from the corona, which is responsible for phenomena like comets tails and aurorae.

The core is responsible for generating energy through nuclear fusion.
The radiative zone allows energy to seep outward in the form of light.
The convective zone transports energy through columns of hot gas.
The photosphere is the only part of the sun visible to the naked eye, as it emits light.

The outer layers of the sun are opaque, so heat needs to move through convection.
The inner layers of the sun are transparent, allowing heat to travel through radiation.
Convection involves warm fluid rising and cool fluid sinking, forming distinct cells.
Radiation involves transporting energy through the emission of photons.

The chromosphere is a layer of gas that is hotter than the photosphere and is visible as a red color during solar eclipses.
Helium was first discovered in the chromosphere before Earth.
The transition region is a thin layer that connects the chromosphere to the corona.
The corona is the outermost layer of the sun's atmosphere, which is very hot and only visible during solar eclipses.
The solar wind is a stream of charged particles flowing constantly outward from the corona and can be seen during comets tails and aurorae.

It is where we see the most light from the Sun, referred to as the "surface".
It is not a sharp edge but an optical effect known as limb darkening.
The photosphere is a relatively thin layer, about 400 kilometers thick, in comparison to the Sun's diameter of 1.4 million kilometers.
Temperatures in the photosphere are roughly 5600 K.
Granules are convection cells about 700-1000 km in size, similar in size to Texas.

The outermost layer of the Sun's atmosphere that extends beyond Earth.
It is extremely hot, reaching millions of degrees Kelvin.
The corona can only be seen during solar eclipses because it is much less bright than the photosphere and needs to be blocked by the moon.

The Sun's core is where energy is generated.
The radiative zone is where energy seeps through in the form of light.
The convective zone is where energy is transferred up in columns of hot gas.
The photosphere is the Sun's "surface" and the only part that can be seen with light.
The corona is visible during solar eclipses.
The solar wind carries hot, charged atoms away, creating comets’ tails and causing aurorae.

The chromosphere is a gas layer hotter than the photosphere, where helium was discovered.
The transition region is a thin layer connecting the chromosphere and corona.
The corona is the outermost layer of the Sun's atmosphere, extending beyond Earth, and is millions of degrees Kelvin.
The solar wind is a stream of hot, charged particles constantly flowing outward from the Sun.

The photosphere is the visible surface of the Sun.
The photosphere has no sharp edge, and limb darkening is an optical effect.
The photosphere has temperatures of about 5600 K.
The photosphere is only about 400 km thick.
Granules are about 700-1000 km in size, which are convective cells boiling to the surface.

The chromosphere is named for its red color seen during eclipses.
The chromosphere is thicker than the photosphere.
The chromosphere is hotter than the photosphere, at approximately 10,000 K.
Helium was discovered in the chromosphere almost 30 years before it was discovered on Earth.

The corona is the outermost layer of the Sun's atmosphere.
The corona extends out beyond Earth.
The corona is extremely hot, reaching millions of degrees Kelvin.
The corona requires a solar eclipse to be seen because of its faintness compared to the photosphere.