The Sun Notes

Layers of the Sun

Sun’s ______

______– where hydrogen fusion happens.

______– energy carried toward surface by radiation (as light).

______– energy carried toward surface by convection (as heat).

Sun’s ______

______– lowest layer – emits visible light – what we see.

______– middle layer – transparent.

______– upper layer – transparent.

The bright visible surface of the Sun is called the ______.

When looking at the Sun, the edges appear orange and darker than the central yellow region. This is known as ______.

Upon closer inspection, the Sun has a marbled pattern called ______, caused by the convection of gases just beneath the photosphere.

During an eclipse, sometimes you can see the layers of the Sun’s atmosphere just above the photosphere, which emits only certain wavelengths of light, resulting in a ______appearance. We call this the sphere of color, or ______.

The solar chromosphere is characterized by jets of gas extending upward called ______.

THE SOLAR CORONA – source of the Solar Wind

Seen in visible light during an eclipse.

This x-ray image shows the million-degree gases.

The Sun undergoes differential rotation.

The rotation period of the Sun’s gases varies from ______days in the equatorial region to _____ days near the solar poles.

Therefore, the magnetic field lines of the Sun become intertwined after several rotations, creating regions of intense magnetic fields and thus producing sunspots and other spectacular features.

The Sun’s Magnetic Field Creates Different Features

______– areas of concentrated magnetic field lines.

______– magnetic loops above sunspots, can carry plasma (hot ionized gas).

______– twisted magnetic field lines relax and release huge amounts of X-rays.

______– twisted magnetic field lines relax and release huge amounts of plasma (up to 4 million mph).

Sunspots

Sunspots have two regions: the inner, darker ______and the outer ______.

Sunspots are regions of intense magnetic fields

The number of sunspots on the photosphere varies over an eleven-year cycle.

Sunspots can be used to determine the ______.

Vital information about Sunspots

Areas of reduced ______

Visible from Earth

______Amount of Magnetic Activity

Can affect ______due to the amount of geomagnetism produced.

Ionized gases trapped by magnetic fields form prominences that arc far above the solar surface.

Sometimes these gases are ejected into space.

Solar prominences

______

Relatively cool clouds of gas suspended above the sun

Controlled by ______

Violent eruptions called solar flares release huge amounts of X-rays. Solar flares are often associated with coronal mass ejections.

On the sun, coronal mass ejections occur when solar magnetic field lines snake around each other, forming the letter "S". Usually, they go past each other. But if they connect, it's like a short circuit. The mid-section breaks loose and drives out a coronal mass ejection.

Coronal Mass Ejections (CMEs) typically expel ____ trillion tons of plasma at up to _____ million mph.

By following the trails of gases released during a coronal mass ejection, we can map the Sun’s magnetic field.

Solar flares

Exploding areas on the sun

Releases huge amounts of ______

Magnetic field and atmosphere protect Earth from harmful effects

______

Cause ______(Northern Lights)

Let’s Review Fusion!!

Hydrogen is the fuel!!!

Nuclei fuse to form Helium and energy as a product

Extreme temperatures are required for fusion to occur due to the repulsive forces of the nuclei (nuclei are positively charged)

The sun is stable because the force of gravity is balanced by the thermal pressure created by the reactions in the core

The Sun is powered by ______, which converts hydrogen into helium. Matter gets turned into energy in the process.

E = mc2

The Sun’s interior is held stable by a balance between radiation pressure forces and gravity, in a condition called hydrostatic equilibrium.

Lifespan of the Sun

Our sun is a less massive star and will end as a ______.

We are currently ______billion years into its lifespan

Two (2) Hydrogen atoms fuse to make One (1) Helium atom theoretically but…

Energy is released as atoms fuse and thus mass is lost as energy

It actually takes 4 Hydrogen atoms to make 1 Helium atom