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In what should be the most beautiful celestial show of the year, the three brightest night-sky objects—Venus, Jupiter, and the crescent Moon—will come together low in the southwest at dusk Dec. 1. Below are some things to ponder while enjoying the view.

The three are different types and sizes of objects, yet they share the common attribute that none makes its own light. All reflect sunlight like three huge mirrors in the sky.

The Moon, which orbits Earth each month, is a moon. As an aside, have you ever wondered why our Moon and Sun don’t have official names? I have. Virtually all the other dozens of moons in our solar system have names, and likewise with most of the other brightest suns. Yet our Moon and Sun, although often capitalized, are officially nameless. Isn’t that a bit like naming all the neighborhood dogs and cats except your own, and then calling yours “the Dog” and “the Cat?” Oh, well.

Venus and Jupiter, as large objects which orbit the Sun, are both planets but their compositions are quite different. Venus, similar to our Earth in size and composition, is a solid terrestrial planet, whereas Jupiter is a huge gas planet some 10 times the diameter of Earth and Venus.

While they all now look close together, they really aren’t. The Moon is nearest at a mere 251,000 miles away. Venus is now nearly 94 millions miles distant with Jupiter now at 540 million miles.

And given their differing distances, light from the Moon gets to Earth in 1.3 seconds, light from Venus arrives in 8.4 minutes, and Jupiter’s light travels 48 minutes before reaching Earth.

Each has differing degrees of reflectivity. Ironically, the brightest of the three, the Moon, is the least reflective. Of the sunlight falling on the Moon’s rocky surface, only 7% is reflected back. It has been said that the Moon’s reflectivity is comparable to that of an asphalt parking lot.

Being perpetually enshrouded in clouds, Venus is the most reflective of the planets, turning back 65% of the sunlight that shines on it. And its outer layers being essentially clouds, Jupiter’s 52% reflectivity almost matches Venus. In case you’re wondering, Earth, 70% covered with water, has a 37% reflectivity.

If the Moon was as reflective as Venus, imagine a full Moon casting nearly 10 times more light than it now does. It would certainly take the romance out of moonlight walks, and there would be little stargazing for much of each month.

* Sky Calendar -

* Dec. 3 Wed. evening: Earliest sunset at latitude 30 degrees N.

*Dec. 5 Fri.: The Moon is at 1st quarter.

* Naked-eye Planets. (The Sun, Moon and planets rise in the east and set in the west due to Earth’s west-to-east rotation.) Evening: Venus is the brilliant “evening star” in the southwest with Jupiter currently to Venus’ upper left. Morning: Saturn is well up in the east southeast.

* November Astro Milestones. Nov. 20 was the 119th birthday of Edwin Hubble (1889-1953), American astronomer for whom the Hubble Space Telescope is named.

Stargazer appears every other week. Paul Derrick is an amateur astronomer who lives in Waco. Contact him at 918 N. 30th, Waco, 76707, (254) 753-6920 or paulderrickwaco@aol.com. See the Stargazer Web site at stargazerpaul.com.