Low Mass Star
Key Stage 4
Meaning
A low mass star is a star with up to 3 times the mass of The Sun.
About Low Mass Stars
- Low mass stars have a different life cycle to high mass stars and exist for far longer than high mass stars.
Lifecycle
- 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 as it becomes much bigger.
- 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.