# Scientists reveal how Santa delivers presents to 900m homes at Christmas

## Santa and his reindeer need to travel at a nearly 45 million km/h to deliver gifts

The Santa Equation: ‘Santa has some extra hours to work with thanks to the different time zones and the rotation of the earth, assuming he travels east to west,’ says scientific researcher Dr David Fleming. Photograph: Conor McCabe

After years of painstaking research, scientists at the National Metrology Laboratory (NML) in Glasnevin, Dublin believe they have unravelled one of the greatest mysteries of Christmas: how Santa delivers his presents to children all over the world on Christmas Eve.

The NML has called their research “the Santa equation” and say it demonstrates how Santa travels 1.5 billion kilometres to visit all of the world’s children in more than 900 million homes in only 31 hours.

“We calculated that Santa and his reindeer need to travel at a whopping speed of nearly 45 million km/h or over 12,000km per second in order to deliver presents to the world’s 2.2 billion children,” said David Fleming, a scientist and lead researcher at the NML.

Mr Fleming added, “Santa has some extra hours to work with thanks to the different time zones and the rotation of the earth, assuming he travels east to west.” This means that science is helping him to visit all of the world’s children in one night, according to the NML.

One of the study’s main findings was the weight of Santa’s sleigh. Scientists working on the project calculated that if the average weight of each child’s present is two kilograms, Santa’s sleigh will weigh more than four million tonnes – that is about 80 times heavier than the Titanic.

Paul Hetherington, head of the NML, said, “We think of presents for children as being one or two presents and you think of Santa’s sack being quite small, but it’s actually an enormous sack and he has to carry huge amounts of presents which amounts to a lot of weight.

“Obviously as he travels the weight gets lighter and lighter as he is offloading a lot of presents, but, nonetheless, that [the weight] was one of the main findings that surprised us,” he said.

When asked what advice scientists at the NML would give children who are hoping to wake up to lots of presents on Christmas morning this year, Mr Hetherington said, “The main thing is always to listen what your parents tell you on Christmas Eve and to go to bed very early”.

Mr Hetherington also offered advise on what food children should leave out for Santa on Christmas Eve: “Santa needs lots of protein for his long journey, so plenty of milk and cookies to keep him going. For Rudolf and his reindeers, carrots are a must to help them see better through the darkness.”