A group of stars appears to give the appearance of a particular shape when viewed from the earth. Our ancestors conceived some shapes in many names are known as a constellation.
These constellations are named on the basis of their shape.
- 1.Ursa major
- 2.Ursa Minor
There are a total of 89 constellations in the sky. The largest of these is the planetarium Centaurus, which has a cluster of 94 stars. Whereas Hydra has a group of about 68 stars.
There are many stars in the constellation called Great Ursa major which has seven more miracle stars that are easily visible. The constellations made of these stars are commonly called the Ursa Major.
The Small Dipper also has 7 stars with more brightness. In the Northern Hemisphere, large sage and small sage constellations can often be seen in spring. Antelope constellations can be seen in winter. The deer is one of the grand planetariums. It has seven bright stars, four of which appear to form the shape of a quadrilateral.
On one corner of this quadrant, one of the largest stars is the star named Bittlegize, while on the other opposite corner is another bright star called Rigel. The other three major star constellations of the antelope lie in a simple line in the middle.
Stars are an astronomical body that continuously emits light and energy. Hence, the Sun is also a star. Stars ratio is 70% H, 28% He, 1.5% C, N and Ne, and 0.5% Fe and other heavy elements.
Stars are three colors-
The color of the star is determined by the surface and temperature. Wires that have low surface heat are colored red. Those with high surface temperatures are white and those with high surface temperatures are blue.
It is the closest star to the Earth after the Sun. Its distance from Earth is 4.22 light-years. The Alpha Centauri is 4.3 light-years away from Earth. All-stars (except the pole star) appear to move from east to west in the night sky, as the Earth itself rotates from west to east on its axis, the stars appear to be moving in the opposite direction from east to west.
Therefore, the virtual movement of stars in the sky is due to the rotation of the Earth on its own axis. The pole star appears to be just above the North Pole and does not change its position over time as it lies on the axis (axis) of the Earth's rotation. The Pole star is a member of the Ursa Minor or Little Bear star group.
Birth and Evolution of a stars
The raw material for star formation is mainly hydrogen and helium gas. The life cycle of the star begins with the accumulation of hydrogen and helium gases in galaxies as dense clouds.
Formation of a Protostar
The life cycle of the stars begins with the condensation of hydrogen and helium in the Akash Ganga, which eventually takes the form of dense clouds. These clouds are called Oort clouds. The temperature of these clouds is -173°C. As the size of these clouds increases, the gravitational force between the molecules of gases increases. When the size of the clouds becomes very large then it, Due to the force of gravity, it shrinks. This shrinking dense gas body is called Protostar. The primordial star does not emit light.
Formation of star from Protostar
The Protostars is a very dense gaseous mass that keeps on shrinking further due to the huge gravitational force. As the initial star begins to shrink, the hydrogen atoms present in the gas cloud quickly collide. These collisions of hydrogen atom increase the temperature of the star. The process of contraction of the initial star goes on for millions of years, during which the internal temperature in the initial star rises from just -173°C initially to about 10⁷°C.
At this extreme temperature, nuclear fusion reactions of hydrogen begin. This process converts four small hydrogen nuclei to form larger helium nuclei and produces vast amounts of energy in the form of heat and light. The energy produced during the formation of helium from the fusion of hydrogen gives a glow to the star and becomes a star.