LESSON-5 Flashcards
(12 cards)
What is a main sequence star?
Any star that has a hot, dense core which fuses hydrogen into helium to produce energy.
What are red supergiant stars?
They are the largest stars in the universe in terms of volume, although they are not the most massive or luminous.
What is a supernova?
It is what happens when a star has reached the end of its life and explodes in a brilliant burst of light.
What is a neutron star?
It is created when massive stars reach the ends of their lives and are composed of the densest matter in the known universe.
How is a black hole formed?
They are made during supernova explosions when very massive stars come to the end of their lives.
Define stellar nucleosynthesis.
The process involving nuclear reactions through which fresh atomic nuclei are synthesized from pre-existing nuclei or nucleons.
What is nuclear fission?
It splits a heavy element (with a high atomic mass number) into fragments.
What is nuclear fusion?
It joins two light elements (with a low atomic mass number), forming a heavier element.
What is a protostar?
It is formed from nebula due to the gravity that pulled Hydrogen gas together until it spins faster and becomes ignited.
What is a red giant?
Forms after a star has run out of hydrogen fuel for nuclear fusion, and has begun the process of dying.
What is a white dwarf?
Stars that have burned up all of the hydrogen they once used as nuclear fuel.
What is a black dwarf?
A white dwarf that has cooled sufficiently to no longer emit significant heat or light.
