Researchers have revealed they are hunting for the elusive Planet Nine in a rather unusual place – medieval tapestries from the Middle Ages.
It’s all based around a new exhibit from Queen’s University Belfast, called “Marvelling at the Skies: Anglo-Saxon Comets and the Quest for Planet 9”. It’s running at the Ulster Museum in Belfast up to Sunday, June 3, 2018.
“Combining records of comets from Anglo-Saxon sources with contemporary images of comets, the exhibition takes visitors on a cosmic journey from the earliest contemporary description of a comet in England in the year 891 under the period of Alfred the Great, to the sighting of a hazy green-hued comet Lovejoy in 2013,” a statement noted.
It’s designed to show the importance of astronomy and science in medieval Europe, and see how that can apply to the history of science. So how does that apply to Planet Nine?
“The Anglo-Saxons could not have spotted Planet Nine... therefore it cannot be portrayed in any tapestries,” the project’s lead, Dr Marilina Cesario, told IFLScience. Instead, they'll look for evidence of it in accordance with models.
Planet Nine is a theorized ninth planet that lurks at the edge of the Solar System. Its existence was proposed back in 2016 by astronomers Mike Brown and Konstantin Batygin from Caltech.
While we haven’t actually seen the planet, its existence is inferred from the odd motions of comets and asteroids in the outer Solar System. These have quite elongated orbits, and it looks like they’re being pulled by an unseen object – a planet.

The hunt has proved tricky so far, but it is still ongoing. Scientists are poring through images of the outer Solar System to see if they can get a glimpse of the planet and prove its existence once and for all.
With the medieval tapestries, the researchers think that records of comets in these tapestries may help test the evidence for the planet’s existence. In other words, if some comets show up according to models that include Planet Nine, then maybe we can add evidence to its existence.
“This research project renegotiates the meaning and importance of medieval science and demonstrates how medieval records of comets can help test the theory of the existence of the elusive ‘Planet Nine,’” Dr Cesario said in the statement.
Dr Cesario’s colleague, astrophysicist Dr Pedro Lacerda, added that it was “fantastic” they were using data that’s about 1,000 years old to look into a modern theory.
“Any strong indication that a ‘Planet Nine’ is required to fit the comet sightings recorded in the Middle Ages will be a unique result and will certainly have a remarkable impact on our understanding of the solar system,” he said.