What are we seeing in this Hubble Space Telescope photograph?
A) Almost every object in the photo is a galaxy, and these galaxies are at many different distances from us.
B) This photo shows the Virgo supercluster of galaxies.
C) Most of the dots in this photo are stars in the Milky Way, but we see a few blotches that represent galaxies beyond the Milky Way.
D) This is the Local Group of galaxies.
A) Almost every object in the photo is a galaxy, and these galaxies are at many different distances from us.
You might also like to view...
Why must the Sun's rate of fusion gradually rise over billions of years?
A) The Sun becomes less efficient and must increase the rate of fusion to produce the same amount of energy. B) Fusion reactions decrease the overall number of particles in the core, causing the core to shrink, converting gravitational potential energy into thermal energy, and increasing the rate of fusion. C) The radiation produced by fusion reactions that is trapped in the core gradually raises the temperature, increasing the rate of fusion. D) The Sun gets heavier as it gets older, and the stronger inward pull of gravity increases the fusion rate. E) The rate of fusion is not rising; it is actually decreasing over time.
A beam of electrons is employed in
A) a gold-foil experiment. B) a cathode-ray tube. C) a LED television screen. D) an oil-drop experiment.
In winter, light-colored clothes will keep you warmer than dark-colored clothes if
a. you are warmer than your surroundings. b. you are at the same temperature as your surroundings. c. you are cooler than your surroundings. d. you are standing in sunlight.
Is heat absorbed or released by ice when it melts?