What percentage of all the matter and radiation density is made of Dark Energy?

There is star formation in Elliptical Galaxies.

Why is Venus hotter than Mercury, even though Mercury is closer to the sun?

The planet that rotates on its axis in nearly the same period as the Earth is:

Which of the following is evidence supporting the Big Bang model?

Put the 8 planets in order from the closest to the sun to farthest. (not all choices will be used)  

A is a small bit of asteroid, comet, or planet out and about in the solar system. When one of these pieces enters the Earth’s atmosphere, we see a flash of light and call it a . If these bits make it to the surface of the Earth, we call them .

Select the correct location for the dwarf planets in the solar system

List the Eras of the Big Bang Theory in chronological order. ____ era ____ era ____ era ____ era ____ era ____ era ____ era ____ era

What is the observed temperature of the Cosmic Microwave Background (CMB)?