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| Astronomy Essentials on Feb 02, 2014

Everything you need to know: Groundhog Day

Groundhog Day comes every year on February 2. It has its roots in astronomy, in the sense that it’s a seasonal festival, tied to the movement of Earth around the sun.

Ah, Groundhog Day. This U.S. and Canadian tradition comes every year on February 2. It has its roots in astronomy, in the sense that it’s a seasonal festival, tied to the movement of Earth around the sun. In the U.S. and Canada, we call it Groundhog Day – a great excuse to go outside and enjoy some revelry during the winter months.

We all know the rules of Groundhog Day. On February 2, a groundhog is said to forecast weather by looking for his shadow. If it’s sunny out, and he sees it, we’re in for six more weeks of winter. On the other hand, a cloudy Groundhog Day is supposed to forecast an early spring.

... the great weather prognosticator, His Majesty, the Punxsutawney Groundhog.  See Phil on the far left?  Image via Wikimedia Commons.

… the great weather prognosticator, His Majesty, the Punxsutawney Groundhog. See Phil on the far left? Image via Wikimedia Commons.

Of course, it can’t be cloudy, or sunny, everywhere. And many towns in the U.S. and Canada have their own local groundhogs and local traditions for Groundhog Day. But by far the most famous of the February 2 shadow-seeking groundhogs is still Punxsutawney Phil. He’s in Punxsutawney, in western Pennsylvania, which calls itself the “original home of the great weather prognosticator, His Majesty, the Punxsutawney Groundhog.”

Since 1887, members of the Punxsutawney Groundhog Club have held public celebrations of Groundhog Day. Punxsutawney is where Bill Murray was in the movie Groundhog Day. From the looks of things … a good time is had by all.

What you might not know is that Groundhog Day is really an astronomical holiday. It’s an event that takes place in Earth’s orbit around the sun, as we move between the solstices and equinoxes. In other words, Groundhog Day falls more or less midway between the December solstice and the March equinox. Each cross-quarter day is actually a collection of dates, and various traditions celebrate various holidays at this time. February 2 is the year’s first cross-quarter day.

Of course, the division of the year into segments is common to many cultures. Our ancestors were more aware of the sun’s movements across the sky than we are, since their plantings and harvests depended on it.

Neo-pagan wheel of the year. Image Credit: Wikimedia Commons

In the ancient Celtic calendar, the year is also divided into quarter days (equinoxes and solstices) and cross-quarter days on a great neopagan wheel of the year. Thus, just as February 2 is marked by the celebration of Candlemas by some Christians, such as the Roman Catholics, in contemporary paganism, this day is called Imbolc and is considered a traditional time for initiations.

The celebration of Groundhog Day came to America along with immigrants from Great Britain and Germany. The tradition can be traced to early Christians in Europe, when a hedgehog was said to look for his shadow on Candlemas Day.

Try this old English rhyme: If Candlemas Day be fair and bright, winter will have another flight. But if it be dark with clouds and rain, winter is gone and will not come again.

Or here’s another old saying: Half your wood and half your hay, you should have on Candlemas Day.

In Germany it used to be said: A shepherd would rather see a wolf enter his stable on Candlemas Day than see the sun shine. There, a badger was said to watch for his shadow.

A friend on Facebook said that, in Portugal, people have a poem about February 2 related to the Lady of Candles. Here is the poem: Quando a Senhora das Candeias está a rir está o inverno para vir, quando está a chorar está o inverno a acabar. Here is the translation: If she smiles (Sun) the winter is yet to come, if she cries (Rain) the winter is over.

Image Credit: WoodTV8

One final note. It’s supposed to be bad luck to leave your Christmas decorations up after Groundhog Day.

The National Geographic Society once studied the groundhog and found him right only one out of every three times. But what the heck? It’s all in good fun. So whether you celebrate with a real groundhog and a real shadow – or just pause a moment on this day to reflect on the passing of the seasons.

Bottom line: This U.S. and Canadian tradition comes every year on February 2. It has its roots in astronomy, in the sense that it’s a seasonal festival, tied to the movement of Earth around the sun. In the U.S. and Canada, we call it Groundhog Day – a great excuse to go outside and enjoy some revelry during the winter months.