Stars Flashcards

Star Classification and Formation

• The Sun is classified as a medium star, distinguishing it from giant stars, white dwarfs, and neutron stars.
• A protostar is created during the initial formation of a star from a nebula.

Star Characteristics and Composition

• Stars shine brightly due to the energy that is released from nuclear fusion, rather than the color they produce or their gravity.
• The primary element that makes up stars is hydrogen, which serves as the main fuel for nuclear fusion.

Stages of Star Development

• The initial stage of all stars begins in a nebula, a massive cloud of gas and dust in space.
• When a star starts to deplete its fuel, the first change observed is the shrinking of the star's core.

Mass and Star Formation

• If a cloud of gas and dust does not possess sufficient mass, a star will not form.
• During the first stage of star formation, gravity serves as the key factor that compacts gas and dust together.

Outcomes of Stellar Evolution

• When a supergiant star exhausts its fuel, it can collapse into a neutron star.
• The sequence leading to star birth begins with gravity pulling gas and dust together, followed by the formation of a protostar.

Sequential Events in Star Lifecycle

• The critical first step in the lifecycle of a star is the gravitational accumulation of gas and dust, prior to protostar formation and nuclear fusion.