Milky Way Essay
Lesson 1
Key Question Answers
1. What does Hubble’s law predict about the speed of a galaxy far away from the Milky Way compared to one that is closer?
Hubble’s law predicted that galaxies were moving away from earth at a rate proportional to their distance from us. The farther away from the Milky Way a galaxy is, the larger the redshift is. The farther away a galaxy is, the faster it is moving away. Conversely, blueshifted galaxies, such as Andromeda, are moving closer to the Milky Way.
2. In a few sentences, describe Hubble’s two major findings about nebulae and explain how they led to the development of the Big Bang theory.
Hubble started working at a California observatory in 1919. Back then the prevailing view of the galaxy …show more content…
Protons must be moving at extremely high speeds in order to collide and fuse. Since they are both positively charged particles, two protons repel each other electrostatically. However, if they get closer than about 10-15mfrom each other, a different force that exists only inside nuclei, overwhelms the repulsive electrostatic force to attract the protons and bind them together.
10. Briefly explain how the nuclear fusion of hydrogen to helium produces energy. Be sure to include E=mc2in your response.
In the equation, E=mc2, E represents energy (in joules), m represents mass (in kilograms), and c2is the speed of light squared. c2can be thought of as a conversion factor between mass and energy. Since cis such a large number, c2is even larger. This means that the tiny amount of mass in hydrogen and helium particles, multiplied by the large c value, results in an enormous amount of joules of energy being released.
11. Two stars, A and B, are within the main sequence on the Hertzsprung-Russell diagram. Star A is bigger than star B. The temperature of Star A is 4500 K and for star B it is 9000 K.
State which star should be more luminous and explain why.
Which star will probably have the shorter lifespan?
Key Question Answers
1. What does Hubble’s law predict about the speed of a galaxy far away from the Milky Way compared to one that is closer?
Hubble’s law predicted that galaxies were moving away from earth at a rate proportional to their distance from us. The farther away from the Milky Way a galaxy is, the larger the redshift is. The farther away a galaxy is, the faster it is moving away. Conversely, blueshifted galaxies, such as Andromeda, are moving closer to the Milky Way.
2. In a few sentences, describe Hubble’s two major findings about nebulae and explain how they led to the development of the Big Bang theory.
Hubble started working at a California observatory in 1919. Back then the prevailing view of the galaxy …show more content…
Protons must be moving at extremely high speeds in order to collide and fuse. Since they are both positively charged particles, two protons repel each other electrostatically. However, if they get closer than about 10-15mfrom each other, a different force that exists only inside nuclei, overwhelms the repulsive electrostatic force to attract the protons and bind them together.
10. Briefly explain how the nuclear fusion of hydrogen to helium produces energy. Be sure to include E=mc2in your response.
In the equation, E=mc2, E represents energy (in joules), m represents mass (in kilograms), and c2is the speed of light squared. c2can be thought of as a conversion factor between mass and energy. Since cis such a large number, c2is even larger. This means that the tiny amount of mass in hydrogen and helium particles, multiplied by the large c value, results in an enormous amount of joules of energy being released.
11. Two stars, A and B, are within the main sequence on the Hertzsprung-Russell diagram. Star A is bigger than star B. The temperature of Star A is 4500 K and for star B it is 9000 K.
State which star should be more luminous and explain why.
Which star will probably have the shorter lifespan?