Stellar Evolution Slides - 2023

© 2023 | Jodivine A. Navarosa Faculty, Research-IS Unit ohuge ball of plasma, which are fueled by the nuclear fusion of hydrogen to form helium within their interiors oA star is characterized according to the following properties: intrinsic brightness and luminosity, mass, and temperature...

© 2023 | Jodivine A. Navarosa Faculty, Research-IS Unit ohuge ball of plasma, which are fueled by the nuclear fusion of hydrogen to form helium within their interiors oA star is characterized according to the following properties: intrinsic brightness and luminosity, mass, and temperature © 2023 | Jodivine A. Navarosa Faculty, Research-IS Unit o Apparent magnitude: indicates the brightness of a star as seen from Earth o Absolute magnitude: indicates the brightness of a star at a standard distance of 10 parsecs (32.6 light-years) o Star ‘luminosity’: the amount of light energy that a star emits from its surface © 2023 | Jodivine A. Navarosa Faculty, Research-IS Unit Hipparchus’ astronomical observations on the stars in the sky were able to help him to classify the stars by how bright they appear. © 2023 | Jodivine A. Navarosa Faculty, Research-IS Unit © 2023 | Jodivine A. Navarosa Faculty, Research-IS Unit Stars vary in color since they vary in temperatures. Colors that may be observed include yellow, orange, red, white, and blue. © 2023 | Jodivine A. Navarosa Faculty, Research-IS Unit Hertzsprung-Russel (H-R) diagram o shows plotted stars according to their sizes, luminosity and surface temperature o The plotted stars include white dwarfs, main sequence stars, giants and super giants. o This diagram further shows that when the luminosity of the stars is plotted against their temperature, the arrangement of these stars in the diagram are restricted to a few well-defined regions. © 2023 | Jodivine A. Navarosa Faculty, Research-IS Unit The life stages that a star undergoes depends greatly on its mass. Since stars are formed in clouds of gas and dust (nebula) that undergo nuclear reactions, the amount of fuel it takes to sustain larger sized stars are higher than smaller ones. Smaller stars tend to burn through their fuel slowly compared to massive stars. © 2023 | Jodivine A. Navarosa Faculty, Research-IS Unit © 2023 | Jodivine A. Navarosa Faculty, Research-IS Unit © 2023 | Jodivine A. Navarosa Faculty, Research-IS Unit