Ch 24.3 - The Sun

Sun in our Solar System

99.8% of the mass in our solar system is the Sun

Plasma

A fourth state of matter made up of superheated gas with a positive electrical charge.

Nuclear Fusion

A process that releases vast amounts of energy. This energy moves outward, toward the outer layers of the Sun.

E = mc2

E = energy released M = mass C = speed of light (300,000,000 mls) Nuclear fusion converts some of the mass from the hydrogen nuclei into energy according to Einstein's equation.

Convective Zone

Hot material from near the radiative zone rises, cools at the Sun's surface, and then plunges back downward to the radiative zone. Convective movement helps create solar flares and sunspots.

Solar Prominences

If plasma flows along a loop of the Sun's magnetic field from sunspot to sunspot, it forms a glowing arch that reaches thousands of kilometers into the Sun's atmosphere.

Plasma

Ionization

Chromosphere

Is a thin zone, about 2,000 km thick, that glows red as it is heated by energy from the photosphere. Temperatures in the chromosphere range from about 4,000 C to about 10,000 C. Jets of gas fire up through the chromosphere at speeds up to 72,000 km per hour, reaching heights as high as 10,000 km.

Corona

Is the outermost plasma layer -- it is the Sun's halo or "crown". The corona's temperature of 2 to 5 million C is much hotter than the photosphere. You can only see this layer during a Solar Eclipse.

Photosphere

Is the visible surface of the Sun, the region that emits sunlight. The photosphere is relatively cool -- only about 6,700 C. The photosphere has several different colors; yellow and red, giving it a grainy appearance.

Radiative Zone

Just outside the core, has a temperature of 7 million C. The energy released in the core travels extremely slowly through the radiative zone.

Gas

No bonds

Without the Sun

Photosynthesis, the basis of our food chain, would stop. The average temperature of Earth would drop to 0 F within a week and to -100 F within a century.

Solid

Strong bonds

Layers of The Sun

The Sun is not a solid or a typical gas, most atoms in it exist as plasma. The Sun is composed almost entirely of hydrogen and helium.

Central Core

The Sun's central core is plasma with a temperature of around 27 million C.

Sun Spots

The most noticeable surface of the Sun are cooler, darker areas that move across its surface.

Photon

Travels only a few millimeters before it hits another particle.

Solar Flares

Violent explorations that release huge amounts of energy.

Liquid

Weak bonds