The Universe is a wonderful creative wonder with stars dotting the skyline. These stars become evident at night, and to the human eye, they all look the same, but are they really the same?
Have you ever wondered: What types of stars exist in the Universe?
Well, the answers are all here. Read on to learn more.
Stars In The Universe
Stars may look the same, but they are classed differently. To date, astronomers are still discovering new phenomena about galaxies, but for now, we know that stars are diverse and have different characteristics.
Man still has a long way to go to learn more about the Universe and the solar system, but here are the stars that are known to us.
Types of Stars
Protostar
Protostar is the nymph of a star. What we mean is that it is the initial form of a star before it is fully formed. Protostar is a collection of collapsed gas from a molecular cloud. This type of star takes about 100,000 years to evolve, and as gravity increases, the protostar is drawn down closer to earth, where it can be seen from earth. Protostar is caused by gravitational heating.
T Tauri Star
Then we have the T Tauri Star. This type is formed and evolves before transforming into a sequence star. A T Tauri star is what is formed after a protostar evolves. Protostars completely evolve at the end of the gravitational pressure phase. Once the T Tauri star is formed, it lacks the gravitational pressure and temperature to generate a nuclear fusion.
They are similar to protostars, but the only difference is that they are larger and brighter and can cover a larger sunspot. T Tauri stars also have extremely strong seller winds and X-ray flares. This type of star maintains this form for about 100 million years.
Main Sequence Star
Main sequence stars are very common. In fact, when you look up at the night skyline to marvel at the stars above, there is the possibility that you are probably looking at the main sequence star. Astronomers believe that the Sun is a sequence star and is similar to the Centauri A, Alpha, and Sirius.
Sequence stars have different sizes, brightness, and Mass. They convert hydrogen into a gas called helium and later release a lot of energy. These stars are said to be in a star called hydrostatic equilibrium. As gravity pulls the star inward, the light pressure from the energy fusion pulls the star outward.
The fascinating thing about these inward and outward reactions is that they balance each other, thereby causing the star to maintain a spherical shape. Main sequence star sizes depend on their mass which is influenced by the strength of gravity pulling them. Also, note that the mass limit of a sequence star is roughly 0.8 times the Sun’s mass or 80 times Jupiter’s mass.
Red Giant Star
A red giant star is a star that has used up all available hydrogen at its core. It no longer experiences fusion and can no longer generate outward pressure to counter the inward pressure pulling it. For red giant stars, hydrogen ignites their core and extends their lifespan, but their shape will increase with time.
This type of star is also called an aging star and is 100 times larger than its previous size when it was a main sequence star. Once the hydrogen deposit is used up, it consumes more helium shells and other heavy elements for fusion reactions.
A Red Giant star only lasts a few hundred million years more before it runs out and becomes a white dwarf star.
White Dwarf Star
A white dwarf star is a transformation of a red giant star. Once the giant star runs out of hydrogen at its core, it lacks the mass to create fusion and eventually becomes a white dwarf star.
The outward light from the fusion stops, and the stars collapse inward. White dwarf stars shine brightly but without fusion reactions and will continue to cool until they become cold as the Universe’s background temperature. This process may take billions of years.
Red Dwarf
Besides white dwarf stars, red Dwarf stars are also very common in the Universe. They are also main sequence stars but have very low mass and are far cooler than the Sun. Red dwarf stars can also retain hydrogen fuel by mixing it at their core so as to conserve energy for a longer time. According to scientific estimates, a red dwarf may take up to 10 trillion years to burn out. Furthermore, the smallest red dwarf star is just 0.075 times the size of the Sun, but it can grow to become half its size.
Neutron Stars
A star that is 1.3-2.1 times the Sun’s mass will not become a white dwarf star when it reaches the end of its life. Rather it becomes by exploding in a catastrophic fashion and what is left of it becomes a neutron star. A neutron star is an exotic star comprising neutrons because the intense gravity it is subjected to crushes its protons to the remaining electrons form neutrons. Extremely massive stars, on the other hand, don’t become neutrons but massive black holes.
