Hertzsprung Russell Diagram

The order in which the greatest blue shift to the red shift of the five distant stars is E, D, B, C, A. The arrows in the diagram represent the speed of movement of the star, the longer the arrow the faster the movement of the star and vice versa. Furthermore, the motion of the source of light is said to be blueshifted if it is moving towards the observer, but if the source is moving away from the observer it is called redshifted (Prather p75). As a result, the star that is moving faster toward the observer will have the greatest blueshift while the star that is moving away from an observer will have the greatest redshift.

It’s called the HR diagram because it tells about the life cycles of stars. By observing and looking at the life cycles of many other stars we can evaluate the date that will tell us all different stages of evolution and growth. While discovering luminosities this helped measure how much energy a star gives off as well as it’s colour that makes categorizing pretty spot on. Because of that a Danish astronomer research combied with russells research based on their spectral types this helped figure out there life cycle of the stars. Even though two women was behind it and it should be named after them but you know how it goes.

This problem wasn't solved until the 1920s, when Edwin Hubble devised the first method of extragalactic distance measurement. His technique relied on stars known as Cepheid variables, whose luminosities can be easily determined by measuring their rates of pulsation. Comparing this luminosity with the stars' observed brightness allowed Hubble to estimate the distance to Cepheid stars in such galaxies, affirming their extragalactic location.

2) Why are there different brightness of stars and how do we describe their brightness as compared to one another?

The area on the H-R diagram where “normal” stars can be found is known as the _________.

R* is the average rate of formation for suitable stars. A suitable star must have an appropriate temperature (i.e. not too hot or cold). It is possible to use the average rate for the galaxy. This can get a bit hazy, as the

The discovery of the heliocentric model

5. On what kind of diagram are stars plotted according to their surface temperature and luminosity?

Out of many things that can scare us, the transformation of a person or environment can truly terrify us. Transformation can be erratic and random, so one cannot expect what would happen next and does not allow us to gain control over it. This truly frightens us. As a little girl watching Ratatouille, I was very scared. Before, I thought that it was the rat that scared me, but I now realize that the abrupt changes in the setting was what actually scared me. For example Remy, the main character, starts off on a roof top, then inside a house, then down a sewage “river” in the first few minutes of the movie. To add on, the scenes changed very quickly not giving me a chance to get used to the environment. It unnerved me that I could not expect what would happen next. Transformation in character and setting can instigate fear in with their erratic nature and can develop an uncertainty of what will happen next. There are many examples in literature where a character or setting goes through a transformation that establishes a sense of fear in the audience. Some examples of transformation creating fear can be seen in “The Fall of the House of Usher” and “Where is Here?” with changes in the characters and abnormal changes of the houses. “The Feather Pillow” also features how transformation can induce fear when Alicia’s health worsens as the monster inside her pillow grows.

(insert diagram of visible spectrum) (further explain the shift is in the line of hydrogen output as stars have lots of hydrogen)

14. Why do stars have different levels of brightness, and how does one describe their brightness as compared to one another?

I can tell many things about the star B-Centauri by looking at this H-R diagram. First of all I can see that it has a temperature of almost 30,000 K, that means it is almost five times hotter than our sun. Next, B-Centauri's luminosity is 10, 000 Lu which means it produces ten thousand times the energy of our sun. I know that B-Centauri is a spectral type O by reading the H-R diagram. During the Vlab we found that Naos was a spectral type O. All stars that are spectral type O are blue, meaning they are the hottest type of stars. Stars of the same spectral type have the same composition. Since Naos has hydrogen, helium, and helium ions so does B-Centauri. The mass of B-Centauri is twenty times the mass of our sun. The radius of B-Centauri

     Stars are a marvelous wonder to many people, that is why some people spend most of their lives wondering what is “above the world so high” (Gardner 98). These people study and map the little twinkling stars in order to get a better meaning of them; they are astronomers. Great astronomers like Edwin Hubble, Immanuel Kant, and William Huggins, never stopped valuing the beauty of the stars. While they developed great astronomical principals. One astronomer who fits this mold most is, Edwin Powell Hubble. Wondering about what was

Understanding of the processes of stellar evolution came as a result of twentieth century advances in both astronomy and atomic physics. Advances in quantum theory and improved models of

Main sequence stars like our own sun enduring in a state of nuclear fusion during which they will produce energy for billions of years by replacing hydrogen to helium. Stars change over billions of years. When their main sequence phase ends they pass through other states of existence according to their size and other characteristics. The larger a star's mass, the shorter its lifespan is. As stars move toward the end of their lives, much of their hydrogen will be converted to helium. Helium sinks to the star's core and raises the star's temperature—causing its outer shell to expand. These large, puffy stars are known as Red Giants. The red giant phase is actually a prelude to a star shedding its outer layers and becoming a small, dense body called a White Dwarf. White dwarfs cool down for billions and billions of years, until they finally go dark and produce no energy at all. Once this happens, scientists have yet to observe, such stars become known as Black Dwarfs. A few stars avoid this evolutionary path and instead go out with a bang, exploding as Supernovae. These violent explosions leave behind a small core that will then turn into something called a Neutron Star or even, if the remainder is large enough, it is then turned into something called a Black Hole.