There is, quite naturally, something about the word ‘star’ that lends itself to speculative fiction. Three of the greatest franchises are linked by the word: Star Wars, Star Trek and of course Stargate. From a scientist’s perspective, and from a communicator’s there is a great scene in an episode from the first season (Torment of Tantalus) where the SG-1 team discover a “Rosetta Stone”, a chamber with the languages of four races, and a fifth ‘key’, a common language based on the chemical elements that assisted with communication.
One of the things that I like about Stargate SG-1 (the first series, continuing the stories set in motion by the film) is the attention to detail. It’s quite realistic in a lot of ways, so for example the SGC (Stargate Command) set up ‘the Iris’ (covering made from initially a real titanium alloy and later a fictional trinium one) to prevent incoming hostiles from accessing the base. But as they start to make allies, they need a way for people to contact them, so they give them blocks of alloys with a unique blend of isotopes that can be analysed when it hits the Iris. And of course there is a certain understated humour, the fact that the SG Teams signal back to Earth to say ‘open the Iris’ is provided by a GDO – Garage Door Opener.
In Stargate, there are lots of interesting technologies, some of which are based on materials not (currently) available on Earth. Some of the plot lines dealt with various attempts to gain access to these materials or the ores from which they are extracted. Arguably the most important of these materials was naquadah, a superheavy mineral (or possibly a metal, it’s not always made clear), which, for a start, all of the stargates were made from.
As of 2016, Tom Lehrer would need to revise his song to build in elements up to 118, Oganesson: other elements named at the same time included 113 (Nihonium), 115 (Moscovium) and 117 (Tennessine). (Element 114 was named Flerovium back in 2012). Recalling the Rossetta stone that I mentioned at the beginning of this post, the four ancient races recognised up to 146 elements. Given that one of these four, ‘the Ancients’, were responsible for the manufacture and placement of the stargates, we can assume that naquadah must be one of these higher-numbered elements.
But doesn’t this give rise to some problems? Aren’t all the higher-numbered elements radioactive? Well, certainly that’s the experience to date. However, we don’t have to appeal to poetic licence, at least, not entirely. Particle physicsists, who make it their business to consider the make-up of atoms and their constituents, have long proposed the “Island of Stability”. Whilst this sounds like a rather bad movie title (possibly one with Harryhausen derived special effects), the theory suggests that there might be some superheavy elements that aren’t completely radioactively unstable. There is some thought that the Island might begin at element 120. Some believe that certain isotopes of the elements mentioned above might begin to show a certain amount of stability, but there is also some difference of opinion as to what stability might mean with some estimates suggesting half-lives measured in the time that it takes to cook an egg (although these are compared with half-lives measured in negligible portions of a second) and some suggesting half-lives in millions of years, which is slightly more useful when trying to set up a galactic wide network of synthetic worm-holes. Ideally, of course, we’re looking for no radioactivity at all, but that might be a bit of an ask.