It’s that time of year when houses are adorned with twinkling lights and decorations with presents under a tree are waiting to be opened. Christmas is approaching. How much attention do you pay to pictures on the Christmas cards you receive or to the paper wrapped around the presents?
You probably don’t worry about it as much as Dr Peter Barthel, an astronomer at the University of Groningen in The Netherlands who found in 2011 that Christmas cards and gift wrapping often depicted the Moon incorrectly. Barthel was spurred into analysis after noticing a UNICEF Christmas card and a popular Advent e-calendar showing an unlikely moonlit scenario.
The scene on the front of the card showed children decorating a Christmas tree beneath a waning Moon crescent, and the calendar also showed carolers under a waning Moon. However, the waning Moon does not rise until 3 am. While it is not impossible for these scenarios to take place, Barthel states that “it’s unlikely” in Communicating Astronomy with the Public.
Barthel examined Christmas books, cards and wrapping paper from The Netherlands and the USA. He found that 40% of pictures in Dutch Christmas books and 65% of Dutch Christmas gift wrap samples incorrectly showed a waning Moon. Artists depicting Christmas scenes in the USA did far better because they usually draw a full Moon with only a few exceptions of...
