The end of the year for teachers and students doesn't really happen in December; it occurs in the merry month of June. In keeping with the scholastic spirit of the season, let's take a short final exam on some of what we've learned here in this column for the last 10 months. Ready?

1. The sky is blue because: a) it reflects the oceans, b) molecules in the atmosphere bounce the blue photons from the sun all over the sky, c) the sky has water in it.

Well, the sky does have water in it, but you can't see it unless it bunches up together into those puffy things we call clouds. And no, the ocean is not reflected in the sky. But the tiny gas molecules in the air do cause the bluer photons from the sun to bounce about in erratic paths giving us the impression the whole place is lit up in blues. Answer: b

2. The summer Milky Way is bigger and brighter than the winter Milky Way because: a) in the summer we face the star-studded center of the galaxy, b) the sun is out longer making the night sky brighter, c) the summer planets just make it appear that way.

There are no "summer planets," so that one is out straightaway. And the sun itself plays no role in a nighttime sky. But our night sky during summer does face toward the billions of stars in the galactic center. During the winter we face the dreary and not-as-well-populated outskirts of the galaxy. Answer: a

3. Which of the following wavelengths of light do we use in astronomy? a) Just the ones we can see, b) Just the sun's wavelengths, c) Gamma rays, d) All wavelengths we can get our curious little hands on.

In the old days, up until the last century, all we could use were the very limited "visible" wavelengths of light, the colors of the rainbow. Now we have telescopes that can tune into just about any wavelength; from long radio waves, through the infrared, ultraviolet, and x-rays, over to the ultra-small and ultra-dangerous gamma rays. And with that, in the last century we have "seen" more of the universe - visible and invisible - than any generation before us in the history of humankind. Answer: d

4. How many stars are responsible for illuminating the Great Nebula in Orion? a) Just one, b) Billions and billions, c) What's this Great Nebula thing?

Seeing images of Orion's great cloud on sites such as Astronomy Picture of the Day, there just has to be an army of stars lighting the whole place up. Alas, no. It is just one hyperactive whiney star in the center that is responsible for providing the energy necessary to ionize the entire region. Answer: a

5. Venus is always seen in the sky: a) on the opposite side as the sun, b) near the sun, c) nobody really know where she will pop up next, that crazy vixen!

Thanks to Newtonian mechanics we know exactly where Venus will be tomorrow - and 100 years from today. And because she is on an inside lane around our star, she will always be in the same vicinity as that great ball of gas, and never on the opposite side of the sky. Answer: b

6. Easter and Passover set their dates by: a) the phases of the moon, b) the phases of the sun, c) the spin of a dreidel.

Well, the sun has no phases. And of course there are no dreidels involved in choosing the dates for high holidays. Both Easter and Passover are dependent on the phases of the moon, specifically the first Full Moon after spring equinox. Answer: a

How did you do? If you are a regular reader here, I'll bet you did well. You can always go back and read the full explanations in our archives of The Skies Above at firstlightastro.com/skiesabove.

Until next time: a) clear skies, b) go learn more about the universe, c) tell others about the wonders of our sweet Home, d) all the above. Answer: d