The Solar System and Stars Flashcards
What are the order of the 8 planets in our solar system, beginning with the closest to the sun?
SUN Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune
What are the stages of a star the same size as the sun?
Nebular —> Protostar —> Main Sequence —> Red Giant —> White Dwarf —> Black Dwarf
What are the stages of a star bigger than the Sun?
Nebular—> Protostar —> Main Sequence —> Red Super Giant —> Supernova —> Neutron Star OR Black Hole
Describe a nebular
Stars form from clouds of dust and gas. Nebulae are large clouds of dust and gas, mainly hydrogen.
All stars begin their lives and a nebular
Describe the features of a Protostar
Gravity causes the dust and gas in a nebulae to become denser and more concentrated.
The temperature increases until Hydrogen and other light elements undergo nuclear fusion.
This produces energy and the core gets bitter and hotter until a protostar is born.
Describe the features of a main sequence star
Nuclear fusion of Hydrogen atoms is now in full flow and a protostar becomes a main sequence star.
This star is much hotter and brighter than before, releasing energy and a flow of radiation from its core.
A main sequence star is in equilibrium; it is stable because the forces of gravity and radiation pressure are the same.
Our Sun is currently in its main sequence stage.
Describe the features of a red giant (low mass star)
At this stage, helium and other light elements in the stars core fuse to form heavier elements.
This process releases even more energy, causing the star to expand.
This star gives off a red light , hence the name red giant.
Describe the features of a white dwarf (low mass star)
A red giant will eventually run out of its fuel of light elements - nothing else in it will fuse.
It will lose its outer layer, leaving behind the core of the star. This is so dense and hot that it glows white, giving rise to its new name.
It is now smaller than before.
Describe the features of a black dwarf (low mass star)
A white dwarf will eventually cool down enough that it stops glowing white hot. Stars like the Sun then fade out, go cold and enter the stage of a black dwarf.
Describe the features of a super red giant (high mass star)
Following the main sequence , Hydrogen fuel begins to run out, and a star begins to fuse helium into heavier elements like iron.
As a result, the gas and radiation pressure will increase, meaning the star expands and becomes a red super giant.
Describe the features of a supernova (high mass star)
A red super giant will start to collapse in on itself and slow the reaction.
This compresses it’s core more and more until it reaches critical point.
This causes a massive shockwave and the supergiant will collapse and explode into a supernova.
During a supernova, gases and dust float out into space, and it is in a supernova that every element heavier than iron will be fused.
Describe the features of a neutron star
After a supernova, only the stars compressed core is left behind.
This core is burned into lots of neutrons and nothing else.
This resulting neutron star is extremely dense… one small amount of a neutron star would weigh more than Earth.
Describe the features of a black hole
In rare cases and if a neutron star is big enough, the core left from a supernova will continue to collapse and keep getting smaller until the entire star collapses into an infinitely small point.
The gravitational field of now so strong that nothing can escape from it, not even light or any electromagnetic radiation… presenting a black hole.
What is luminosity ?
Luminosity is how much radiation and power a star has. It can also be described as how bright a star is. The bigger and blue-er the star, the more luminous it is.
What is a light year?
The distance light travels in a year.
What are rocky planets and what are the gas planets?
Rocky planets are the inner 4 planets to the sun and have a rocky, terrestrial surface.
Gas planets are the outer 4 planets from the sun, and are made up of just gases.
