What is Hertzsprung-Russell Diagram?
Hertzsprung-Russell Diagram is a tool that astronomers and astrophysics use to classify different types of stars. Sometimes it is called the color-magnitude (cmd) diagram. Color and heat are x axis. They share the axis because the color and heat correlate each other very well. About 3500 to the surface temperature, the stars are red, up to about 4500 K are orange, up to about 6000 K are yellow, up to about 9000 K are white and further blue. Some stars, such as Wolf-Rayet stars, have surface temperatures up to 25,000 K.
Absolute size/luminosity is Y axis y Hertzsprung-Russell diagram. Axis of X -axis can again share two variables because these two are correlated. Absolute size is measured using a standard luminance scale, while the luminosity side is measured in terms of solar units. The solar units are the logarithmic scale because the stars range from 1/100,000 sun to ~ 100,000 times. During the supernova September star as clear as five billion times withLunka, although it is only temporary.
Hertzsprung-Russell Diagram shows that the stars cluster into several natural categories: the main sequences (dwarves), of which our Sun is a member of the stars connecting hydrogen; white dwarves who have exhausted their nuclear fuel and are in the cooling process; and subgiants, giants and supergiants that combine elements heavier than hydrogen, such as helium.
White dwarf stars are much smaller than the sun: they have a diameter of the Earth's diameter! This is because the white dwarf is the rest of the core of the star that previously generated its own energy. Dwarf stars are much larger, the surrounding of our sun. The giants are much larger, as large as Mars orbit. This is because they combine their nuclear fuel faster, warm them and expand the envelope.
The standard star name comes from the Hertzsprung-Russell diagram. For example, if the star isRed and in the Supergiant class, it is called red supergiant. Our sun is a white dwarf. There are yellow giants, blue giants, orange dwarves, red dwarves and many other well -known categories of stars.