unto dust shall thou return'." Naming In Northern Lights, Lord Asriel reveals the origins of the term "Dust" to be from a passage from the slightly alternative version of the Bible in Lyra's world: "In the sweat of thy face shalt thou eat bread, till thou return unto the ground; for out of it wast thou taken: for dust thou art, and unto dust shalt thou return." — Dust was previously known (in Lyra Belacqua's universe) as "Rusakov particles" named after their discoverer, Boris Mikhailovitch Rusakov. Rusakov discovered a field permeating the universe that enabled consciousness, before the discovery of Dust; its existence was predicted, as: "the existence of a Rusakov field implies the existence of a related particle". In our universe, Mary Malone researches dark matter, referring to it as "Shadows" or "Shadow particles". The name "Shadows" was given to the particle by her colleague, Oliver Payne, in references to Plato's Allegory of the Cave, involving "shadows on the wall". When she communicates with Shadows by interfacing with her detector, it confirms that they are the same as Dust and dark matter. The Mulefa, who are able to see Dust directly, use the word "sraf" accompanied by a leftward flick of the trunk (or arm for humans) to describe it. Nature and characteristics In the multiverse of His Dark Materials, the characters perceive Dust visually; scholar Amanda M. Greenwell observes that "at no point does any character touch, taste, hear, or smell Dust." While the human eye is unable to see Dust unaided, multiple characters still manage to "see" it.Attempts to see and interpret Dust, or see and appreciate evidence of it in other visual manifestations, drive the action of the entire trilogy—which suggests that Pullman's work, insofar as it employs this investigation into visual literacy, is largely about the way the human subject chooses to perceive the world around him.At the start of Northern Lights Lord Asriel is one of the few to have seen Dust, but only with the aid of "photograms" taken with "a new specially prepared emulsion". He shows the scholars at Jordan College a slide show, revealing Dust as "a fountain of glowing particles". Pullman himself has stated that the "projecting lantern" that Asriel uses was based on childhood memories of his own grandfather's magic lantern. When Dust is first mentioned in Northern Lights, it seems to be something negative; only later do Lyra