Few Christmas carols evoke the season of peace and goodwill as readily as Silent Night. Two popular stories contribute to its appeal: one concerning the circumstances of its composition in Oberndorf, near Salzburg in Austria, and the other its role in the Christmas Truce of 1914 when the opposing forces walked out of their trenches to greet their enemies and share food and drink.

But its lyrical and musical content are also important factors in understanding its enduring popularity, and Christmas Eve 2018 marks the 200th anniversary of its performance.

Let’s be honest – environment news isn’t always the jolliest, and 2018 was no exception. From climate change, to recycling, to energy policy, at times it has felt like we’ve been lurching from one crisis to the next.

So here are ten upbeat environmental stories from this year that prove it’s not all doom and gloom.

Wind turbines are a leading source of green energy which could supply 12% of the world’s energy by 2020. But their use is often criticised for its impact on wildlife, particularly birds. Larger birds can collide with turbines and some have even learned to avoid flying near them.

Half a century of Christmases ago, the NASA space mission Apollo 8 became the first manned craft to leave low Earth orbit, atop the unprecedentedly powerful Saturn V rocket, and head out to circumnavigate another celestial body, making 11 orbits of the moon before its return. The mission is often cast in a supporting role – a sort of warm up for the first moon landing. Yet for me, the voyage of Borman, Lovell and Anders six months before Neil Armstrong’s “small step for a man” will always be the great leap for humankind.

From the Neolithic to present times, the amount of sunlight we see in a day has had a profound impact on human culture. We are fast approaching the winter solstice for the Northern hemisphere, which takes place on December 21. This is the longest night of the year – once celebrated as “Yule” by the pagan people of Northern Europe before it became Christmas.

Christmas and the holidays are a time to relax and celebrate with family and friends. But the festive season can also be a time of unwanted weight gain that won’t budge once the holidays are over.

Research (mostly from the United States) has found adults typically gain 400 to 900 grams over the holidays.

No-one wants to miss out on the celebrations. But knowing more about the kilojoule content of your favourite Christmas treats can help you make conscious decisions about which foods and drinks to have and enjoy, and what portion sizes to choose.