For more than 2 billion Christians around the world December 25 marks the date of Jesus' birth. So it was sure to cause a stir when astrophysicist Neil deGrasse Tyson used the day to celebrate the birth of another man entirely.

On Christmas Day the American astrophysicist and author tweeted in celebration of the life of physicist and mathematician Isaac Newton, born on December 25, 1642.

Self-titled servant of cosmic curiosity: Neil deGrasse Tyson. Credit:Patrick Pay

By Sunday Tyson's birthday message had been retweeted more than 68,000 times and had clearly caused an upset, with many labelling the tweet disrespectful and a "troll" on Christmas.