Jimmy Westlake: ‘The Southern Cross’ | SteamboatToday.com

Back to: Explore Steamboat

Jimmy Westlake: ‘The Southern Cross’

On a recent trip to the Big Island of Hawaii

On a recent trip to the Big Island of Hawaii, Colorado Mountain College astronomy professor Jimmy Westlake, right, and students, from left, David Edelman, Todd Campbell and Mollie Wunder took a moment off from their sunset-to-dawn Messier Marathon on Mauna Kea, the world's tallest mountain, to pose beneath the stars of the Southern Cross, visible just above Westlake's head.

"When you see the Southern Cross for the first time,

You understand now why you came this way…"

I think these lyrics from the hit song by Crosby, Stills and Nash sum up most people's feelings about seeing the constellation of the Southern Cross for the very first time.

Although it is the tiniest of the 88 official constellations, its reputation is larger than most, even though most people living in the Northern Hemisphere have never seen it. Its likeness adorns the flags of New Zealand and Australia.

The Southern Cross, or Crux, as it is now officially named, used to be visible from much of Europe, but no more. It originally was seen by the ancient Greek civilization around 1000 BC and was then considered to represent the hind feet of a giant Centaur pictured in the stars. Throughout the centuries, however, the slow wobble of the Earth on its axis (called precession) carried the stars of Crux south and out of view of Greece and the rest of Europe, so it gradually was forgotten. European sailors rediscovered these stars during the 16th and 17th centuries as they began exploring the southern seas. Many of these European explorers were of the Christian faith and were awestruck by the resemblance of these stars to a tiny crucifix in the heavens.

Amerigo Vespucci himself claimed to be the first European to ever see these stars during his third voyage in 1501, but the four stars forming the Southern Cross didn't appear on star charts as separate and distinct from the Centaur constellation until Dutch astronomer Petrus Plancius depicted Crux on his celestial globe in 1589. It officially became the smallest of our 88 constellations in 1920.

Crux is not visible in its entirety from any location north of 27 degrees latitude, which includes most of the United States. April and May are the best months to observe it. I've seen the top star of the Southern Cross briefly pop up above the southern horizon from New Orleans and witnessed the entire cross barely clear the ocean waves from Key West. It wasn't until I traveled to the Big Island of Hawaii that I could see the Southern Cross standing well above the southern horizon. Eventually, precession will carry Crux back into the view of mid-northern latitudes once again, but that will be centuries in the future. Until then, traveling to the tropics is the only way to view the Southern Cross for yourself.

Professor Jimmy Westlake teaches astronomy and physics at Colorado Mountain College's Alpine Campus. He is an avid astronomer whose photographs and articles have been published all around the world. His "Celestial News" column appears weekly in the Steamboat Pilot & Today newspaper. His "Cosmic Moment" radio spots can be heard on local radio station KFMU. Check out Jimmy's website at http://www.jwestlake.com.