Merry Christmas and Happy Hanukkah! Others prefer Happy Holidays, Seasons Greetings or Cheery Solstice. The last one I made up and hopefully wont catch on. December 22nd is the start of winter in the Northern hemisphere, and summer in the southern half of the globe. It certainly has astronomical connections, with the Earths axis in the North tipping the furthest away from the Sun.
What would the sky on Christmas Eve, look like from the North Pole? Glad you asked. Few have seen it, though people in Northern Alaska and Canada, as well as Scandinavia and Siberia, have nearly the same sky. The North Star lies within a half degree from the North Celestial Pole, marking where the Earths axis of spin points. The North Star, therefore, is just about exactly overhead as seen from the North Pole.
We in the latitudes of Northern Pennsylvania see the North Star not quite half the way up the sky; in fact the Northern boundary of the state follows 42 degrees North Latitude. Thus, the North Celestial pole is 42 degrees above the horizon as seen from that line. You need not drive many hours, north or south, to notice the difference. The area of the sky around the North Star that does not sink below the horizon is called the Circumpolar region. Constellations within that region for Wayne County are most of Ursa Major, including the Big Dipper; Ursa Minor (the Little Dipper), Draco the Dragon, Cepheus the King, Cassiopeia the Queen and Camelopardalis the Giraffe.
At the North Pole the ENTIRE SKY that you see, is circumpolar, never setting below the horizon! Skimming the horizon is what is referred to as the Celestial Equator, which you might imagine, rides straight overhead as seen from Earths equator.
Polar Bears, adventurers and Santa and his company, also have a perpetual view of the Northern Lights, the Aurora Borealis. This shimmering glow in the highest reaches of the atmosphere, forms a wide ring in the sky, but is not inscribed around the spot next to the North Star. Instead, the fiery ring is off-center.
The auroral ring is centered over the North Magnetic Pole, which is located off shore of the most northern islands of Canada, south of the Earths North Pole of rotation, but within the Arctic Circle. There are southern counterparts, of course, in Antarctica. The magnetic poles are slowly moving. Year to year, the magnetic pole slowly moves across the globe. Scientists have charted its movement for over 170 years. In that time, it has wandered approximately 683 miles northward. The magnetic pole, however, shivers in its motion on a daily basis by varying amounts, inscribing an oval. It has been known to jolt back and forth as much as about 25 miles in a day.
Currently, Northern Lights are not seen as often from Scandinavia or Siberia, or points south of these areas, because the magnetic pole is on North Americas side. Tell that to Vladimir Putin. Anyway, if the magnetic pole keeps on its present course, it could reach Siberia in about 50 years. This information was found on the web site for the Geological Survey of Canada.
Keep your compass handy as you trek north for your winter vacation!
Orion, the champion of winter evening sky constellations, lies right on the Celestial Equator. This places Orion about half way up the in the southern sky as seen from min-northern latitudes. In the Arctic, Orion rides the horizon, right at his mid-section, the famed three stars of the Belt.
Now get this- the North Pole which marks the rotation of the Earth, also slowly moves, over thousands of years. About 16,000 years ago it was in central North America. That would put Santas workshop probably close to Des Moines, Iowa.
Friday night December 21 is the longest night of the year- a bonanza for star lovers, who alas, are reminded that they too must get a good nights sleep sometime. At least at this time of year, the sky is dark in early evening so you neednt stay up long to see the stars.
Thats not quite the Christmas Star you see shining brilliantly in the southwest during the evening. Thats the planet Venus! Jupiter is also glowing bright, high in the southeast in the early morning hours.
New Moon is on December 29.
Be blessed this Hanukkah and Christmas season.
Keep looking up!
Peter Becker is Managing Editor at The News Eagle in Hawley, PA. Notes are welcome at email@example.com. Please mention in what newspaper or web site you read this column.