Fiscal cliff, Middle East unrest, looming tax increases, genetically modified foods, Joe Biden, the decline of American civilization — so many problems plague us moderns.

But at this time of year, those issues must take a backseat to the question that looms above all others as a major concern to friends of Christmas around the world:

Who is faster at delivering gifts — Santa Claus or Superman? Billions of children looking forward to presents on Christmas morning eagerly await science’s answer.

Let’s start with the Man of Steel. Fortunately, we have solid evidence of his speed capabilities in the 1978 documentary “Superman: The Movie,” directed by Richard Donner.

In that film, Lex Luthor commented that even Superman couldn’t catch two missiles going in opposite directions.

The missiles in question top out at about Mach 23, or approximately 15,500 miles per hour. From Luthor’s comment, we may assume that Superman was significantly faster than one missile, but not fast enough to catch the other speeding missile while covering the increasing distance between them before the second missile’s impact. A fair assumption, then, for Superman’s standard top speed would be between 20,000 and 30,000 miles per hour.

That’s pretty fast, but in the same film, Superman is shown going into space and orbiting the Earth so fast that he reverses time, meaning in a vacuum he is capable of speeds faster than light. Presumably he cannot do that in Earth’s atmosphere without lighting the planet on fire, so for the sake of the Christmas question, we’ll discount superluminal capabilities.

However, when he first enters space and before he enters time warp, Superman is shown orbiting the Earth in about one second. Since the Earth has an average circumference of about 24,900 miles, that puts his top in-atmosphere speed at somewhere around 89.6 million miles per hour.

Now you might be tempted to conclude that’s it, case closed, there’s no way jolly old St. Nick could compete with Kal-el.

Oh ye of little Christmas faith.

While there exist many movies about Santa Claus, none of them is really considered a documentary of the caliber of Donner’s effort, unless you might argue for the first “Santa Clause,” which while thoroughly researched relied upon re-creations and made some debatable claims. (I mean, magic snowglobes? give me a break.)

Still, we can extrapolate quite a bit from what is known as solid facts about Santa Claus. (Children, pay attention and put on your Christmas math caps.)

There are about 2.3 billion Christians in the world, whom Santa has to visit within a 24-hour period, starting and ending at the International Date Line. If you figure an average family size of four people, that means 575 million stops for St. Nick, which works out to almost 24 million stops per hour.

Each stop consists of travel time, gift delivery and consumption of milk and cookies. For the sake of argument, we’ll assume each activity requires an equal amount of time, which means that after subtracting time for gift delivery and cookie consumption, Santa actually only has one-third of an hour for travel between each of those 24 million stops.

Now we need to figure an average distance. Within cities, of course, the homes will be quite close together, but out in rural areas, which take up most of the land in most nations, houses can be several miles apart, and towns can be hundreds of miles apart. Areas near oceans can be thousands of miles apart. To account for this disparity, let’s assume then an average distance between stops of two to four miles.

Calculating 24 million stops in one-third of an hour, with an average two to four miles distance between means Santa Claus and his reindeer must be able to hit speeds of 144 million miles per hour or higher between stops. It also means Santa and the reindeer must wolf down their cookies and milk like living garbage disposals.

Now it remains a subject of debate whether Santa and his sleigh team can actually enter space, but they exhibit certain advantages over Superman that make North Pole technology superior to anything Krypton has to offer.

For instance, the sleigh is a heat-resistant lifting body designed by the elves in conjunction with Lockheed to skim along the top of the troposphere, providing superior aerodynamics over distances.

The reindeer’s antlers are actually a clever swing-wing design that folds back and flattens out as speed increases, lowering the team’s drag profile.

Most importantly, Rudolph’s famous red “nose” is actually a high-tech laser device that heats the air in front of the reindeer to more than 2,000 degrees, greatly decreasing the air pressure and effectively “pulling” Santa’s sleigh through even the coldest storm front.

Superman could, in theory, perform a similar trick with his heat vision, but he apparently hasn’t caught on yet, and Santa’s not ready to relinquish the title of Christmas speed king yet, so he’s not talking.

So Superman’s symbol may be a big red S that’s known around the world, but at Christmastime, that big red S is owned by Santa.

Merry Christmas.