There is always such a terrific buildup approaching Christmas, and then it is just — gone. The very concept of Christmas, so ubiquitous, so powerfully inspirational and evocative, so marketable! Gone like a burst bubble or a melted snowflake. We’re left standing in a pile of polypropylene ribbon and debris, tired, a piece of fruitcake in our hand. Come on, fruit cake is an acquired taste, just try it.

The winter solstice fell on Dec.21. The days are getting longer, but not so’s you’d notice.

For my friends in Australia, Dec. 21 was the summer solstice; for them, each day is a little shorter than the day before. Happy New Year, wherever you are on the planet!

The other day my friend Moira — who lives right here in the Northern Hemisphere–observed that the days appear to be growing shorter.

But, I said, the Winter Solstice was on Dec. 21. The days are getting longer.

After pondering a moment, Moira suggested that maybe, since the days have been steadily decreasing in length for so many months, they will keep on getting shorter for a while. Comparing the phenomenon to a boulder that gathers speed as it rolls downhill, she theorized that once the tendency to get dark earlier day by day was well underway it would be pretty difficult to stop it, the Winter Solstice notwithstanding.

While I felt intuitively that Moira was wrong, I was as usual stymied by her logic. Moira said she would speak to her brother, who took physics, about it.

“Are you writing your column?” Moira’s 13-year-old daughter, Daphne, inquired. “Because if you are, could you work in eponymous hippopotamus somewhere?” Daphne likes words. I told her I didn’t think so and handed her a Christmas cookie.

“In the Chinese Zodiac, 2026 will be the Year of the Horse, and the Greek word for horse is hippo. Hippopotamus is Greek for river horse,” I told her.

“What kind of icing is this?” Daphne asked dubiously, and off they went to the Ausable Club golf course to sled.

It takes Earth approximately 365 days to orbit the sun, which means that an Earth year is 365 days, except for leap years, which occur pretty much every four years, except for century years not divisible by 400. I would gladly elucidate this quirk and expound upon the differences between the Julian and Gregorian calendars but I am allotted only so much space in the paper.

The Chinese New Year will begin Feb. 17. It is based on the lunar calendar, so it won’t fall on the same date every year. According to the “South China Morning Post” the Year of the Fire Horse can bring chaos but also great progress.

(A pygmy hippo named Moo Deng was born about a year ago in Thailand, but try using the word eponymous with a name like Moo Deng!)

Some might assume that every planet in the Solar System would be celebrating its New Year soon, but that is not the case. The orbital period of Mars is 687 days, for example, so a Martian year is almost twice as long as an earth year. The next Martian New Year, according to a system arbitrarily made up by scientists and numbered, for some reason, Year 39, falls on Sept. 30, 2026.

According to NASA, “Mars is the only planet we know of inhabited entirely by robots.” Named for the Roman god of war, Mars is orbited by two potato-shaped little moons, Phobos and Deimos.

Phobos is expected to crash into Mars in about 50 million years, a fact that I’m sure Elon Musk has taken into account in his plan to found an enduring settlement in order to perpetuate the human race on the red planet. Of course a lot can change in 50 million years.

For example, NASA has determined that Mars once had a dense atmosphere, warm temperatures and plenty of water.

Today, because its atmosphere is so thin, if you were to stand on the surface of Mars on the equator at noon, it would feel like spring at your feet — 75 degrees Fahrenheit — and winter at your head — 32 degrees Fahrenheit.

Aha! I have just learned that in the coming Planet Mars Year 39, an eponymous hippopotamus will turn one year old. Yes, baby pygmy hippo Mars, born in Tanganyika Wildlife Park, Kansas.

Have a great year.

(Martha Allen, of Keene Valley, has been writing for the News since 1996.)