Why does the Big Bang theory predict that the cosmic background radiation should have a perfect thermal radiation spectrum?
A) The background radiation came from the heat of the universe, with a peak corresponding to the temperature of the universe.
B) The spectrum of pure hydrogen is a perfect thermal radiation spectrum.
C) The spectrum of 75 percent hydrogen and 25 percent helium is a perfect thermal radiation spectrum.
D) The light from all the stars and gas in the sky averaged over the entire universe is a perfect thermal radiation spectrum.
E) It doesn't predict that the cosmic background radiation should have a perfect thermal radiation spectrum.
Question 2
What evidence supports the hypothesis for a vast, deep ocean which once occupied what is now the northern plains of Mars?
A) many of the largest flood channels appear to have drained into the northern plains
B) geographic features that look like ancient shorelines
C) that the rock along the proposed shoreline is sedimentary rather than volcanic
D) all of these are evidence
The four ways in which animals exchange heat with the environment are radiation, evaporation, convec
Violating Background Assumptions
What Happens to Incoming Solar Radiation?
Greenhouse gases absorb part of the outgoing IR radiation
The Cosmic Calendar: Concepts of Time