Sun, Stars and Exoplanets

Life cycle of a low mass star. (6)

1. Star forming nebula

2. Prostar

3. Main sequence star

4. Red giant

5. planetary nebula

6. white dwarf

Life cycle of a high mass star.

1. Star forming nebula

2. Prostar

3. Massive sequence star

4. red supergiant

5. supernova

Super nova goes either neutron star or a black hole.

What is a star forming nebula.

Dust and gas that contains hydrogen. Rotation causes concentration making a disc and prostar over time.

What is a prostar.

Thermonuclear reactions cause it to heat up and release lots of energy. Gases expand and clump. Lasts around 1 million years.

What are main sequence stars.

last 90% of their lives. Billions of years. Hydrogen become helium through fusion. Created energy and consumes hydrogen.

What are red giants?

Hydrogen runs out and the core heats up. Star turns red and hellium becomes carbon. Lasts 2 billion years.

What are planetary nebulas.

Outer part of red giants become a nebula surrounding the core that has become a white dwarf.

What is a white dwarf.

leftover core of a red giant that cools over billions of years.

What are Massive sequence stars.

Stars that are larger. Fusion countinued with carbon. Lasts millions of years. Makes magensium, Neon, Sodium, and Aluminium

What are red supergiants.

massive stars that swell and go through fusion. Created silicon, argon, and Iron. Will eventually collapse.

What are supernova.

Red supergiant explodes.

What are Neutron stars.

Result of supernova. The protons and elctrons combine to make dense formation of neutrons.

What are black holes.

Result of supernova. collapses further and makes a point of infinite density. Singularity. Nothing can escape them.

What are the 7 layers of the sun. + one extra.

1. Core

2. Radiative Zone

3. Convection Zone

4. Photosphere

5. Chromosphere

6. Corona

7. Solar winds

Sunspots.

What is the core?

Hottest, Nuclear energy. H-He

What is the radiative zone?

Protons go slow through this zone and interact with atoms. They lose energy. Last millions of years.

What is Photosphere?

Low pressure zone. Atoms are far apart allowing photons of light to escape.

What is chromosphere.

Low pressure zone. can be seen in eclipses has a red glow.

What is the Corona.

Protons and electrons escape gravity, Part of suns atmosphere. Solar wind comes from here.

What are solar winds.

Outermost zone of atmosphere. interfere with life on earth and space. Charged particles that come from corona.

What are sunspots.

Dark spots on the sun that are colder and are caused by more magnetic activity.

How do star clusters help us study the life cycle of stars?

We cant be here to witness stars whole life spans. We instead observe clusters to see stars in various stages of their lives.

What are globular clusters?

Symmetrical and round. Hundreds of Thousands of stars. Older and have lots of red giants.

What are open clusters.

Young and not very many stars gas and dust zones.

What are stellar assosiations?

Young stars that are bright. They are close together.

What are exoplanets?

Planets outside of our solar system.

What is the wobble method? Advantages and disadvantages?

Large telescopes are used to detect gravitational pulls on stars by planets.

Expensive and cant detect smaller planets

Can find large bodies well. Works with any orbits.

What is the transit method? Advantages and disadvantages?

Uses many small telecopes to detect dimming in stars due to planets passing in front of them.

Cheaper and can detect most sizes of planets. A little hard to see smaller planets still.

Needs specific orbit to be able to see.

What are gas giants?

Large, Like jupiter and saturn. They can be close to their stars.

What are Neptune-like-planets?

Size of neptune and uranus. Atmospheres of hydrogen and hellium with rock cores.

What are super earths?

Terrestrial. Can have atmospheres but not always. Larger than earth but extremely light.

What are terrestrial planets?

terrestrial. Earth sized or smaller. Made of rock, silicate, carbon, and water. Could have life.

What is the convection zone?

Layer of the sun where bubbles of gas are constantly keeping the layeer in motion. Outside of radiative zone.