Types of Stars

Types of Stars

Introduction

Stars come in a vast array of sizes, temperatures, and colors. Astronomers classify stars based on these characteristics. Let’s explore some of the primary types of stars.

Main Sequence Stars

Most stars, including our Sun, are main sequence stars. These stars are fusing hydrogen into helium in their cores. Their mass determines their temperature, luminosity, and lifespan.

main sequence star

Giants and Supergiants

As stars age and run out of hydrogen fuel, they expand to become giants or supergiants. These stars are larger, cooler, and more luminous than main sequence stars.

• Giants: These stars are larger than main sequence stars but smaller than supergiants. They have cooler temperatures and are often reddish in color.
• Supergiants: These are the largest and most luminous stars. They are extremely hot and can be blue, white, or red in color.

giant star and a supergiant star

White Dwarfs

After a star like our Sun has exhausted its nuclear fuel, it collapses into a dense, hot core called a white dwarf. It gradually cools over billions of years.

white dwarf

Neutron Stars and Pulsars

Massive stars end their lives in catastrophic supernova explosions. The core that remains can collapse into an incredibly dense neutron star. Some neutron stars emit regular pulses of radiation, known as pulsars.

neutron star and a pulsar

Black Holes

The most extreme outcome of stellar evolution is a black hole. If a star is massive enough, its core can collapse to a point of infinite density, creating a black hole with a gravitational pull so strong that nothing can escape.

black hole