Difference between revisions of "Lifecycle of a Star"
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| − | #[[Nebula]] | + | #[[Nebula]] - A huge cloud of [[gas]] and dust stretching across space which collapses due to [[gravity]] to form [[star]]s. |
| − | #[[Protostar]] | + | #[[Protostar]] - A glowing ball of [[gas]] and dust that is not yet hot enough for [[Nuclear Fusion|fusion]] to occur in its core. |
| − | #[[Main Sequence Star]] | + | #[[Main Sequence Star]] - The longest and most stable period of a [[star]]s life when the outward pressure caused by [[Nuclear Fusion|fusion]] of [[Hydrogen]] in its core is balanced by the inward [[pressure]] caused by [[gravity]]. |
| − | #[[Red Giant]] | + | #[[Red Giant]] - A [[star]] that has run out of [[Hydrogen]] for [[Nuclear Fusion|fusion]] so the [[pressure]]s are no longer balanced and its core collapses under [[gravity]] until the core is hot enough to [[Nuclear Fusion|fuse]] [[Helium]] into more [[massive]] [[element]]s. During this time the outer layers expand as the [[star]] cools but becomes brighter. |
| − | #[[White Dwarf]] | + | #[[White Dwarf]] - A [[star]] which as run out of low [[mass]] [[element]]s to [[Nuclear Fusion|fuse]]. There is no more outward [[pressure]] due to [[Nuclear Fusion|fusion]] so the core collapses due to [[gravity]] into a ball of [[Iron]] and continues to glow for millions of years as it [[radiation|radiates]] its [[Thermal Energy Store|thermal energy]]. |
| − | #[[Black Dwarf]] | + | #[[Black Dwarf]] - Once a [[White Dwarf]] has cooled enough it will no longer glow and become a [[Black Dwarf]]. These [[star]]s do not yet exist because the [[Universe]] has not existed long enough for [[White Drawf|White Dwarves]] to cool. |
====High Mass Star==== | ====High Mass Star==== | ||
Revision as of 10:07, 13 March 2019
Contents
Key Stage 4
Meaning
The lifecycle of a star is the set of distinct stages in a stars existence marked by its composition, behaviour and colour.
About The Lifecycle of Stars
- The stages in the lifecycle of a star depends upon the mass of the star. More massive stars tend to have shorter lives and more violent deaths.
Low Mass Star
- Nebula - A huge cloud of gas and dust stretching across space which collapses due to gravity to form stars.
- Protostar - A glowing ball of gas and dust that is not yet hot enough for fusion to occur in its core.
- Main Sequence Star - The longest and most stable period of a stars life when the outward pressure caused by fusion of Hydrogen in its core is balanced by the inward pressure caused by gravity.
- Red Giant - A star that has run out of Hydrogen for fusion so the pressures are no longer balanced and its core collapses under gravity until the core is hot enough to fuse Helium into more massive elements. During this time the outer layers expand as the star cools but becomes brighter.
- White Dwarf - A star which as run out of low mass elements to fuse. There is no more outward pressure due to fusion so the core collapses due to gravity into a ball of Iron and continues to glow for millions of years as it radiates its thermal energy.
- Black Dwarf - Once a White Dwarf has cooled enough it will no longer glow and become a Black Dwarf. These stars do not yet exist because the Universe has not existed long enough for White Dwarves to cool.