The University Record, November 13, 1995

Teske says rare planetary encounter
will take place Nov. 19

Venus, Jupiter and Mars come together in November to present Michigan skywatchers with a rarely seen spectacle, according to astronomer Richard Teske.

"These three bright planets have been drawing closer in the southwestern sky all this month," Teske says. "On Nov. 19, just after sunset, the three planets will occupy an area of the night sky just a little larger than the full moon. Our next chance to see such a close alignment of the three planets will be in the year 2152."

Teske says that Michigan skywatchers should look for the planetary get-together beginning around 15 minutes after sunset on any November evening, with the 19th marking the high point of the show.

"Find an observing site with a good, clear view of the southwestern horizon, so that you can see the setting sun," he says. "The planets are located low in the sky, a little southward (to the left) of the place where the sun has gone down. See if you can watch them as they descend toward the horizon along the slanting path followed by the sun. Venus outshines the others, with Jupiter next in brilliance. As the evening sky darkens, fainter Mars will become visible. Binoculars or a small telescope may help you spot Mars if observing conditions are unfavorable."

All three planets currently are located on the other side of the sun from Earth. On Nov. 19, Jupiter lies 570 million miles away and Mars is 210 million miles away. Venus is closest at "only" 140 million miles.

According to Teske, it is common for two planets to appear almost lined up and close together in the sky as seen from Earth. But it is unusual for three of them to be nearly aligned.

"Astronomers call these events `conjunctions,'" Teske explains. "The two star players in this month's conjunction, Venus and Jupiter, get together almost every year---around 70 times a century, in fact. Sometimes they pass one another in the sky with less than a moon's width between them. Venus and Mars present similar close conjunctions 25 or 30 times each century. All three planets line up only about twice each century, but rarely do they huddle together as closely as they do this month."

Although close conjunctions of planets like this one provide fine pictures for photographers and amateur astronomers, they have no value for scientific research. Professional astronomers won't be making any special observations of the planets during November.

"The evening display this month closes with an appearance of the crescent moon above the three planets on Nov. 24, just as they are slowly separating," Teske says. "Weather permitting, Michigan observers will find this a fitting end to a rare celestial exhibit."