The Sun and Stars Webquest

The sun fuses 4 HYDROGEN nucleus/atoms into 1 HELIUM nucleus/atom. During NUCLEAR FUSION the sun converts matter (elements) into energy (radiation) in the CORE of the star. The sun fuses 4 HYDROGEN nucleus/atoms into 1 HELIUM nucleus/atom. A result of this is the creation of massive amounts of RADIATION ENERGY. Convection currents move energy from the core to the surface.

Sunspots are darker/cooler areas on the surface of the sun Sunspots are darker/cooler areas on the surface of the sun. They are caused by strong magnetic fields that slow down convection so less energy is released. The sunspot cycle begins when we start to see a slow increase in the number of spots. Eventually the number of spots will grow into the hundreds. This cycle lasts around 11 years. As astronomers observed sunspots they realized they were moving. This helped us to understand that the sun was rotating.

Solar flares are violent explosive releases of energy from the surface of the sun. The flares seem to happen when there are a lot of sunspots present. Solar flares send electrically charged particles into space called solar wind. Solar wind can cause magnetic storms that damage satellites.

Auroras are caused by the mixing of solar wind with the earths magnetosphere. Auroras are usually seen soon after a large solar flare.

The main factor that shapes the life and eventual death of a star is its mass/size. The star that will live the longest will be a small or extra small mass star because it burns cooler and slower. A star with the same size as our sun will stay in the main sequence stage for 10 billion years. The main factor that shapes the life and eventual death of a star is its mass/size.

A supernova is the explosion of a dying high mass star. small mass star: Main sequence large mass star: During the MAIN SEQUENCE stage hydrogen is fused and creates a helium core. The main fuel for the sun is hydrogen gas. During the Red Giant stage helium is fused and creates a carbon core. The main fuel for a Red Giant is helium gas. When fusion is done in a red giant the core of the White Dwarf will be mostly made of carbon. A supernova is the explosion of a dying high mass star. A black hole is an object so dense that even light can’t escape it.

Lifecycle of a Star: Nebula cloud- gas and dust particles held together by gravity. Gravity crushes the center of the cloud until fusion begins and the cloud ignites. Main Sequence- hydrogen atoms fuse into helium atoms in the core of the star Red Giant- hydrogen atoms are almost gone, the outer shell of gases expands and grows larger. Nebula/Supernova- small mass stars lose their outer shell and return to a nebula, large mass stars explode into a supernova. White Dwarf/Black Hole- the core of small mass stars slowly burns out, the core of large mass stars caves in on itself and forms a black hole.

Astronomers use spectrographs and spectral lines to identify the elements that are present in a star. They analyze the spectral lines from the light of a star. Each element has its own spectral lines. Kind of like a finger print.