Galaxy and Dense Gas Passes

Comparing a yellow star, a blue star, and a red star, we could determine Just from color that the hottest star was the 10. One. BLUE Rotation curves of spiral galaxies show that stars' orbital speeds don't drop off with distance from the galactic center as expected, and thus imply the existence of . The main sequence includes the following kinds of stars: B) Hot, blue, large, massive ones and cool, red, small, low-mass ones 12. Which of the following was not an era In the history of the universe?The phases of the moon are caused by D) The alignment of the Earth/moon/sun system making a different portion of the Spectra help us determine the composition of astronomical objects because A) Each element, compound, or ion has a different set of spectral lines. 15. Dark energy is the most important factor in the of the universe. A) Accelerating 16. Universe scenario for the fate The outer planets are more massive than the inner planets because C) Both of the above 17. The three basic types of galaxies are B) Spiral, elliptical, and irregular. 8. A planet orbiting a star feels a force due to the star's gravity that C) Increases with the star's mass and decreases with the square of the distance. 19. Massive main sequence stars A) Have hot cores, use their hydrogen rapidly, and go supernova after a short life. 0. Hubbub's law gives us an indirect way to measure a galaxy's D) Distance. 21. We can determine an object's temperature from its thermal (or â€Å"blackbody') spectrum by finding the wavelength at which it emits the most electromagnetic radiation.Galileo findings from his telescopic observations were revolutionary because he showed that the heavens were not perfect. B) FALSE 28. If the sun had begun fusion later, so it did not clear the solar nebula of its remaining gas so soon, Uranus and Neptune might have become as large as Jupiter and Saturn are now. A) TRUE 29. If the sun somehow instantaneously became a 1 solar mass black hole, the Earth According to Hubbub 's law, the reediest of a distant galaxy is directly related to its temperature. B) False