explain evolution of stars
Answers
Answer:
Stellar evolution is the process by which a star changes over the course of time. Depending on the mass of the star, its lifetime can range from a few million years for the most massive to trillions of years for the least massive, which is considerably longer than the age of the universe.
Answer:
The interior of a typical main sequence star is illustrated by the internal conditions of the Sun, with the highest density, pressure, energy generation rate, and temperature occurring at the very center. The temperature dependency of the proton‐proton cycle means that energy is produced over a fairly large volume in the stellar center, out to about 25 percent of the total stellar radius in a star like the Sun.
Within this core, the star's chemical composition slowly changes as hydrogen is converted to helium (see Figure ). In the 4.6 billion years since the Sun formed, it has used about one‐half of its hydrogen at the very center. This slow progressive conversion of light‐weight hydrogen to fewer nuclei of heavier hydrogen is accompanied by slow changes in other physical factors in the stellar interior and related slow changes in the star's surface conditions. In due course, when all hydrogen in the core is exhausted, a star must make more dramatic changes in its structure. To a biologist, changes that occur in the lifetime of a living organism are referred to as aging. Astronomers refer to the aging of a star as stellar evolution.
Explanation:
