President Kennedy famously launched the Apollo programme with the words, We choose to go to the Moon … not because [it is] easy but because [it is] hard.

I sometimes joke to my research group, in a spirit of rueful disclosure, that we do these things, not because they are easy but because we thought they would be easy.

That’s because I have a habit of enthusiastically springing ideas on my students and collaborators, bundled with optimistic assessments of the time needed to work through their details. Of course, the devil famously lurks in the details, so weeks often turn into months or even longer. We do usually get there in the end, and it is almost always worth the journey.

And so it is with writing this blog.

A year ago, I announced a reboot, along with a list of potential future topics:

• Science communication — why do it and why I do it.
• The limits of naked eye astronomy, and how that shaped the development of physics.
• Seeing the shape of the solar system in the evening sky. 
• Moana (the movie) and the overall shape of the universe. 
• Children’s books and the discovery of galaxies.
• The continued decline and fall of Twitter.
• The numbers of people on bikes in Auckland, and what we can learn from crunching the data.
• A recap of my own favourite posts over the years.
• Dark matter – has it already made successful predictions? (Spoiler: YES!) 
• Academic freedom – where does it start, where does it end, and why it matters. 
• Crank mail: what drives “amateur” physicists, and does it make them happy?
• What’s an excursion set, and why did I choose it as the name for my blog?

I’ve got notes for most of these posts, and I finished, let’s see, precisely none of them. I did write other posts, however – including several on space technology and rocketry (this, this and this one), while others offer a peek inside a physicist’s head (that, that and that one).

Another thread was New Zealand’s approach to science spending (e.g. this one, albeit actually from late 2023); the year saw major policy changes, few of them good. My piece on our unfortunate involvement with MethaneSAT drew the most attention; it was “syndicated” by Newsroom and cited by several follow-up stories (e.g. here and here). There are several shoes left to drop on that fiasco, and I am sure I will return to that topic, and science strategy more broadly, in 2026.

---

On a more upbeat note, cosmology is a small, globally connected field and over the years it has taken me around the world more than a few times. November 2025 found me in Japan for a conference. Longtime readers may recall that I once wrote about the physics of Kogetsudai at Ginkakuji temple in Kyoto. This year’s trip gave me the opportunity to renew my acquaintance with the place itself, a highlight of my year.

Another high point for the year: my colleagues and I landed a Marsden Council Award. This supports New Zealand’s links to the LISA gravitational wave mission and the Vera Rubin Observatory, both major global enterprises in fundamental science.

This big win – for me, my group and for New Zealand – is rendered somewhat bittersweet by the Marsden Council Awards being one of things that will be unavailable in the future, thanks to the government’s decision to reduce support for fundamental research in science and the humanities.

To quote another part of JFK’s speech,

The quest for knowledge and progress is determined and cannot be deterred… [and] will go ahead, whether we join in it or not.

To that end, my personal goal, as ever, remains twofold. Firstly, to make sure that we join in this quest as best we can. And, secondly, to help our leaders grasp the value of ambition and excellence as clearly as JFK.

---

If you are keen to keep track of this project my other science, my research group’s website is the place to look.

Just a reminder that you can sign up for my newsletter of this blog. In a note to new subscribers, I promise that it is both “eclectic and low-traffic”. I evidently deliver on this undertaking, with around one post a month on topics from rockets to UNESCO registered sandcastles.

I am happy to consider suggestions for topics for 2026, even if my inability to stick to a plan means I cannot promise to actually heed any of them. Although, perhaps my mention of Ginkakuji today allows me to claim a minimal delivery on the “my favourite posts” item in the list above?

So thank you for reading – and even more so for subscribing. And that’s Excursion Set wrapped for 2025. Enjoy your holidays.

---

Header Image: Pohutukawa flower from Wikimedia – a sparkly harbinger of Christmas in these parts.