means that the star is further away P7.3.4 define a parsec (pc) as the distance to a NA NA star with a parallax angle of one second of arc P7.3.5 calculate distances in parsecs for simple NA NA parallax angles expressed as fractions of a second of arc P7.3.6 recall that a parsec is similar in NA NA magnitude to a light-year and is the unit used by astronomers to measure distance P7.3.7 recall that typical interstellar distances NA NA are a few parsecs P7.3.8 recall that the luminosity of a star NA NA depends on its temperature and its size P7.3.9 explain qualitatively why the observed NA NA intensity of light from a star (as seen on Earth) depends on the luminosity star’s and its distance from Earth P7.3.10 recall that Cepheid variable stars pulse NA NA in brightness, with a period related to their luminosity P7.3.11 recall that and explain qualitatively how NA NA this relationship enables astronomers to estimate the distance to Cepheid variable stars P7.3.12 understand the role of observations of NA NA Cepheid variable stars in establishing the scale of the Universe and the nature of most spiral nebulae as distant galaxies P7.3.13 recall that telescopes revealed that the NA NA Milky Way consists of millions of stars and led to the realisation that the Sun was a star in the Milky Way galaxy P7.3.14 recall that telescopes revealed the NA NA existence of many fuzzy objects in the night sky, and that these were originally called nebulae P7.3.15 recall the main issue in the NA NA debate: whether spiral nebulae were objects within the Milky Way or separate galaxies outside it
means that the star is further away P7.3.4 define a parsec (pc) as the distance to a star with a parallax angle of one second of arc NA NA P7.3.5 calculate distances in parsecs for simple parallax angles expressed as fractions of a second of arc NA NA P7.3.6 recall that a parsec is similar in magnitude to a light-year and is the unit used by astronomers to measure distance NA NA P7.3.7 recall that typical interstellar distances are a few parsecs NA NA P7.3.8 recall that the luminosity of a star depends on its temperature and its size NA NA P7.3.9 explain qualitatively why the observed intensity of light from a star (as seen on Earth) depends on the star’s luminosity and its distance from Earth NA NA P7.3.10 recall that Cepheid variable stars pulse in brightness, with a period related to their luminosity NA NA P7.3.11 recall that and explain qualitatively how this relationship enables astronomers to estimate the distance to Cepheid variable stars NA NA P7.3.12 understand the role of observations of Cepheid variable stars in establishing the scale of the Universe and the nature of most spiral nebulae as distant galaxies NA NA P7.3.13 recall that telescopes revealed that the Milky Way consists of millions of stars and led to the realisation that the Sun was a star in the Milky Way galaxy NA NA P7.3.14 recall that telescopes revealed the existence of many fuzzy objects in the night sky, and that these were originally called nebulae NA NA P7.3.15 recall the main issue in the debate: whether spiral nebulae were objects within the Milky Way or separate galaxies outside it NA NA
Physics%20final.docx