Chapter 14 science cornell notes- The sun

Forces in Balance

Nuclear fusion in the sun's core produces a lot of energy. This causes gas ions within the sun to move very fast, generating a lot of pressure towards the Earth's core. This pressure would cause the sun explode, if not for the balancing force on the outside of the sun. This balancing force is the sun's gravitational pull. As a result, the sun is stable.

The photosphere

PHOTOSPHERE- this is the inner layer of the sun's atmosphere. This is considered like the sun's surface, even though the sun doesn't have a surface. This is where visible light is present, so what we see is actually the photosphere.

PROMINENCES

PROMINENCES- are huge, reddish loops of gas that often link different parts of sunspot regions. Sunspots usually occur in groups. When they are near the edge of the sun, you can see the prominences almost reaching out to Earth off from the side of the sun.

SOLAR FLARES

SOLAR FLARES- are the eruptions of heated energy fro, prominences connecting, which converts large amounts of magnetic energy into thermal energy. It is gas that explodes.

sunspots

SUNSPOTS- are areas of gas on the sun's surface that are cooler than the gases around them. These appeared as dark spots on the sun. They appear to be small, but they can be as big as Earth. Sunspots seem to move on the sun, which shows that the sun rotates on an axis, like the Earth.

Solar wind

Solar flares can greatly increase the solar wind from the corona. This results in an increase in the number of particles reaching Earth's upper atmosphere. If they enter, they can create powerful electric currents that cause gas molecules in the atmosphere to glow. The result os rippling sheets of light in the sky called auroras. They can also create magnetic storms, which can disrupt radio, tv, and telephone signals, and electrical power problems.

Pictures:

solar flare

Features of the sun

using telescopes, scientists have observed many things about the sun. They noticed features on and just above the sun including sunspots, prominences, and solar flares.

The chromosphere

CHROMOSPHERE- is the middle layer of the sun, it is the layer that gives off color, originating from the greek word chroma. When you see the solar eclipse, the reddish you see after is in the chromosphere layer.

The corona

CORONA- is the outer layer of the sun, this means crown in latin. It almost looks like a white halo around the sun. It extends into space for millions of kilometers. It can turn into solar wind. SOLAR WIND- into a thin stream of electrically charged particles that the corona turns into.

The sun's interior

Like Earth, the sun has an interior and an atmosphere. The sun's interior consists of the core, the radiation zone, and the convection zone.

The CONVECTION ZONE

The CONVECTION ZONE- is the outer layer of the sun. Hot gases rise form the bottom of the convection zone and they gradually cool as they approach the top. Cooler gases sink, forming loops of gas that move energy toward the sun's surface.

NUCLEAR FUSION

The sun shines brightly which provides energy for the Earth. This energy is created by the sun through nuclear fusion. However, it was hypothesized that the energy was created from a chemical reaction, which was wrong, because the sun has been burning for about 4.6 billion years, which would prove that theory to be incorrect. NUCLEAR FUSION- is a process in which two atomic nuclei combine to form a larger and more massive nucleus that releases energy. This can only happen in conditions of extreme high pressure and temperature, which occurs at the Earth's core. CORE- is the central region, in this case, of the sun. The temperature reaches about 15 million degrees celsius. The missing mass from the conversion of hydrogen to helium is changes into energy, thus being nuclear fusion. This energy slowly creeps out of the sun, and can reach Earth in the forms of heat and light.

The sun's atmosphere

The sun's atmosphere includes the photosphere, the chromosphere, and the corona. Each layer has unique properties.

Summary:

The sun, like the Earth, has inner layers and an atmosphere. The inner atmosphere includes, the core, radiation zone, and convection zone. In the core, that's where there is lots of pressure, and heat, and nuclear fusion takes place. In the radiation zone, it is dense, and slows releasing energy down. Finally in the convection zone, gas is cooled as it approaches the top. The atmosphere is made up of the photosphere, chromosphere, and the corona. The Photosphere is the light layer, The chromosphere layer is the color layer. Finally, the corona is the last layer that stretches very far, and can be turned into solar wind.

The RADIATION ZONE

This is the middle layer of the sun. The RADIATION ZONE- is a region of tightly packed gas where energy is transferred mainly in the form of electromagnetic radiation.Due to this layer being so dense, energy can take more than 100,000 years to move through it.

The core

This is where energy is produced. It is under lots of pressure, and heat. This enables nuclear fusion to take place. The core of the sun has a diameter of about 400,000 km.

Chapter 14 Section 2 Energy from the sun

Unlike Earth, the sun doesn't have a solid surface. The sun is a big ball of ionized gas called plasma. About 3/4 of the sun's mass is hydrogen, about 1/4 of the sun's mass is helium, and there is a small percentage of other elements.