As we follow the universe backwards in time from the present, the density and the temperature .

Which of the planets fits the following description: “A planet with a solid, crater surface which is alternately very hot and very cold, and having no atmosphere”?

Although the Sun rises in the East and sets in the West, the Moon does not.

The universe is roughly ] dark matter, dark energy, and ordinary matter.

Which planet of our Solar System has the highest mass?

Which of the following is the most accurate description of the formation of the Solar System?

In our Galaxy, young metal-rich stars are found

A geologically dead moon would show

Edwin Hubble discovered Hubble’s Law when he plotted the          of galaxies.

What would you expect the overall color of a globular cluster to be?