Life Cycle of St

Life Cycle of Stars

Terminology

Main Sequence: A star that is actively fueling hydrogen into helium in its core.

Low and Medium mass stars: Small mass stars, or red dwarfs burn at a low temperature (for a star) for a long time, as they use up their hydrogen very slowly. They can live up to 100 billion years.

At the end of their lives, they get warmer, and eventually become white dwarfs, and then burn out.

Medium mass stars, like our sun, burn at a higher temperature and more quickly. They live to about 10 billion years.

They are stable (in the main sequence) for most of their lives, and then they grow larger, turning into red giants. After that they collapse, with the out layer becoming a planetary nebula, and the core of a white dwarf becoming a black dwarf.

Planetary Nebula: an expanding, glowing shell of ionized gas expelled by a dying low or medium mass star late in its life.

High Mass Stars: Large mass stars burn extremely hot and fast. They don’t live longer than 7 billion years, and often a lot less.

After spending a while in the main sequence, they grow larger and become supergiants, and after they explode, it becomes a supernova.

There are two options for a supernova.

If it was a large star, it would implode to make a neutron star, which is a small, extremely dense star.

If it was a very large star, it would implode to make a black hole. A mass so dense that nothing can escape from its gravity, even light.

Solar Phenomena

Solar Radiation, the flow of energy from the sun to the earth. It is the reason why life on Earth exists.

Sun Spots are cooler regions of the sun's surface caused by the sun’s magnetic field. They can last from a few days to a few months, and the number of sunspots varies upon the eleven year cycle of the sun’s magnetic field.

Solar Prominences are large, bright curved streams of particles extending outward from the surface of the sun. related to the magnetic field. They can last from several hours to several weeks.

Solar Flares are explosions on the surface of the sun that shoot out hot plasma into space over the course of a few minutes to a few hours.

An extremely large kind of solar flare is called a coronal mass ejection, this can cause an aurora and damage orbiting satellites if pointed towards the Earth.