By Peter Becker
Itís that time of year when children around the world surely ponder a great (sort of) scientific mystery. Do reindeer follow the classic system of celestial navigation when tethered to an over-burdened sleigh? While we have not heard of any reindeer flying out of northern Scandinavia or Alaska, according to the popular account, there is a band of eight on the north polar ice sheet that do just that.
A hardy bunch they must be; too bad penguins in Antarctica, which at least have wings, donít pitch in and fly north on Christmas Eve. Of course, in the southern hemisphere, summer has just begun, and below the Antarctic Circle, the only star they could see in the sky is the Sun.
For the north polar cap reindeer, however, their sky is full of stars, especially once they gain enough altitude above any cloud cover.
Heading south from the North Pole, they would not have the North Star ahead of them, although they would as they face north for the trek back on the 25th.
There is no clear consensus of what hour on the 24th of December the herd makes its annual migration southward. By all accounts, they arrive at their destinations along the way after children are sleeping. When that would be on the 24th is up for grabs. Ask any parent. Nevertheless, these reindeer likely stop along the way not far from the north polar cap, probably in isolated Inuit villages in northern Canada. That would mean they would have to depart rather early. Fortunately, since winter began on December 21, above the Arctic Circle, the Sun stays below the horizon.
As for celestial navigation in the animal world, there is precedent for the supposition that this particular band of reindeer could follow the stars. A great deal of the marvelous arts and sciences of mankind have already been done in nature. Well before sailors kept track of constellations to chart their way across the ocean, migratory birds may have been doing the same thing.
According to the Encyclopedia Britannica, homing experiments have demonstrated the ability of animals to orient themselves geographically. A variety of species of both birds and fish are believed to follow landmarks, including land topography, rivers, air masses and in the case of fish, familiar currents. There is a hypothesis that migratory birds act like a compass, being sensitive to the Earthís magnetic field. No sensory organ, however, has been found to support this.
Birds that migrate by day appear to be able to tell direction from the angle of the Sun. Studies of night migratory birds have been done under planetarium domes. These birds actually appear to respond to the star patterns.
Various insects also appear to be guided by the Sun. Mammals that migrate appear to follow visual landmarks. Bats, however, may use some form of true navigation to reach their caves.
What about reindeer? The normal reindeer migrates on land as far as 3,100 miles a year. A herd will move at bout four miles a day. A search of reindeer information showed nothing about being guided by the stars. This special band of eight reindeer on Christmas Eve must be extra special.
Of course we all know they have extra help from a ninth reindeer with a nose rivaling the bright red star Betelgeuse, in the constellation Orion.
Whether zoology supports other examples of fauna with a luminous proboscis, - let alone one emitting photons in the long (red) wavelengths of the electromagnetic spectrum- we are yet to determine with any reasonable degree of scientific certainty. In other words... Rudolph is one of a kind.
Last quarter Moon is on Christmas Day Dec. 25. Look east-northeast after dark for brilliant planet Jupiter trying to pose as the Christmas Star.
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