What do you mean there isn’t any dark matter?


One of the more trivial consequences of the pandemic and the various lockdowns and ongoingrestrictions was that it thwarted my plan to join the local astronomy society, Astrocantabria, in early2020. I had been poised to fill in the form and was already looking forward to my first monthly talk when everything was shut down … for what turned out to be a couple of years. It took even longer forthe new normal to begin to resemble the old normal again, but last month I finally ran out of excusesfor not getting my act together and signed up and paid my subscription. And I went along to the talk atthe start of February, only having to run for the last 100 metres to get there on time, which is pretty good for me.

After a brief summary of recent missions to the moon, which was mostly familiar stuff and allowed meto sit and listen with a smug smile in spite of the speed with which the first speaker delivered his talk (in Spanish, remember!), the evening’s main speaker discussed galaxies of different shapes and sizes, both ‘nearby’ and far, far away (and formed a long time ago). The James Webb Space Telescope was mentioned often, of course, and the questions from the audience at the end of the talk quickly developed into a debate about an anomalous distant and ancient galaxy that has recently been in the news. If it had a nice name I probably still wouldn’t remember it, but it doesn’t. Explaining that this particular galaxy has puzzled a considerable number of astronomers by not being at all like it’s supposed to be according to the most popular cosmological model – both because it’s more complex than it should be and also because it doesn’t seem to contain as much dark matter as it should – the speaker went on to admit that he wasn’t at all convinced about the existence of dark matter!

I felt like I had just emerged from a cave. I had no idea that not believing in dark matter was an option. I checked Wikipedia (standard, knee-jerk response) and found that the dark matter concept goes back even earlier than Zwicky’s dunkle materie in the 1930s (Poincaré and matière obscure, anyone?), when it was discovered that the outer regions of galaxies rotated much more quickly than they should,given their observable mass. And, of course, the fact that the expansion of the known universe seems to be accelerating – instead of slowing down – is generally said to be due to ‘dark energy’, the idea being that the stuff we can actually see (galaxies, stars, planets, black holes, dust and gas etc.) is a very small percentage of what’s out there.

As far as I can tell, the NASA people still seem to be happy with this notion, as do the boffins at CERN, who sound optimistic about proving the existence of dark matter one day if only by spotting an otherwise inexplicable ‘amount of energy and momentum “missing” after a collision’. But so far they haven’t been able to repeat the success they enjoyed with the discovery of the elusive Higgs boson, have they? (For some reason, I hear Han Solo saying, ‘Don’t get cocky, scientists!’)

Of course, my opinion on the subject carries no weight at all (or has zero gravitational effect, if you prefer). And yet I find it hard not to side with those I’ve heard objecting to the dark matter theory on thebasis that it explains the anomalies that observations present by proposing a type of matter and energy which, by definition, we simply can’t detect! In other words, they can’t prove they’re right, and we can’t prove they’re wrong. It’s great fun coming up with theories, but I’ve always had a soft spot for scientists who say, ‘We just don’t know!’

Anyway, going back to the moon briefly before I sign off, I can’t resist mentioning the Intuitive Machines’ IM1 lander, Odysseus, which touched down on the lunar surface on 22 February, more than fifty years after Appollo – and promptly fell over rather like the Japanese lander in January! To be fair, people have pointed out that this is a mission launched by a private company (albeit with a hefty chunk of funding from NASA) and that it cost around 0.1 percent of an Appollo mission (if I heard that right). Even so, if it had been launched by The Company, in my fictional world, I’m fairly sure it would have stayed upright!

Book news next month, even if it’s ‘only’ a new edition.

Leave a Comment

Your email address will not be published. Required fields are marked *