What is dark matter? Why is there so much of it? How was it formed? We don’t have even guesses that might try to answer these questions. We know that dark matter must exist, because, like all other material in the Universe, it generates gravity. The same fundamental force that holds us to the Earth, and that keeps the Earth in orbit around the Sun, is the only sign that dark matter is prepared to give us that it even exists. In fact, without the gravity of dark matter, galaxies could not have formed or held together. Particles of gas would never cluster closely together enough to make stars. We owe our very existence to this silent, invisible fluid that fills the Universe.

Although we cannot yet explain dark matter, we can use powerful computer simulations to visualise it. These incredible animations show us that the Universe is spanned by interlocking gossamer filaments of dark matter, millions of light years long. Normal material gathers whether the threads of dark matter join and interlock. It is at these intersections where galaxies form, and where stars are born, live and die.

And so the stars, we realise, are not scattered like random dust across the Universe. Rather, like trophies of some cosmological spider, galaxies have been carefully pinned onto the cosmic web at the positions where the dark matter filaments mesh together.

Our efforts to study the swirls and smudges continue unabated. But we now know that this glittering celestial display is only a tiny part of the story. And just as in the night sky, colour and light are what draws our initial attention to Giles Ryder’s work, but the true form and structure is in the reflections and invisible threads. Ryder’s pieces are not just held in place on their podiums and platforms by their own weight, but are bound together by hidden filaments into a complicated, much grander whole.

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Professor Bryan Gaensler is an astronomer and Federation Fellow at The University of Sydney.