Hertzsprung-russell Diagram :: essays research papers

The Hertzsprung-Russell diagram or, the H-R Diagram for short, is a graph which plots stars according to their temperature and absolute order of order of order. This graph reveals a pattern, which in fact is quite interesting. The H-R Diagram is named for the two astronomers, Ejnar Hertzsprung and Henry Russell, who observe this pattern of stars. These two astronomers independently discove rubicund that comparing magnitudes and spectral word form (color) of stars yielded a lot of information about them. One key intend of the H-R diagram is to show the relationship between temperature and absolute magnitude of stars. The instance of temperature measurement used is chiliad, where the zero point is equal to -273.16 C. On the H-R Diagram, the temperature of degrees Kelvin ranges from 3,000 to 30,000. The absolute magnitude of stars on the H-R Diagram ranges from +15 to -10. Absolute magnitude is how bright stars would appear if they were positioned at 32.6 light years away from ea rth. On this scale, the dispirit the number, the brighter the star. Thus, a start with an absolute magnitude of -10 would be oft brighter than a star with an absolute magnitude of +15. The two astronomers found many an(prenominal) patterns after developing their graph. They found that 90% of stars graphed fell within a band that ran through the middle of the graph. These stars range from cool, dim, red stars at the lower right of the H-R Diagram to hot, bright, blue stars at the pep pill left coigne of the H-R Diagram. The stars that fall into to this band are known as main-sequence stars. Stars such as the sun, and almost every start visible in the night flip over fall within this band of main sequence stars. There is some other group of stars which are cool and bright that appear confining the upper right corner of the H-R Diagram. These stars are very large and therefore shed very big surface areas. These large surface areas give aside large amounts of light and this ma kes the stars bright. Most of these stars are known as red giants. Some are so large however that they are referred to as supergiants. Red giants have a temperature of about 3,500 degrees Kelvin and an absolute magnitude of around 0. Supergiants have a temperature of around 3,000 degrees Kelvin and an absolute magnitude of about -7. Another group of stars, which are rather small, is found near the bottom left of the H-R Diagram.