Back in May, the internet went wild after Reddit discovered that when exposed to light, the gatefold sleeve to David Bowie’s Blackstar revealed a star field. As it turned out, there wasn’t any crazy chemical process going on — it was just translucent paper. Still, it was pretty cool, and in a new interview with BBC Radio 6, graphic designer Jonathan Barnbrook, who did the artwork for the album, reveals that there are other hidden secrets to be discovered.

“There are a number of black stars in the album as well,” he explains. “It’s not just the five-pointed star on the front. And they do symbolize different things in life. For instance, there’s the rosette which looks a little bit like a price ticket. That’s to say, well, this is still a commercial product; you still buy it. There’s the guiding star, the idea of a person who you follow in your life or the idea of something spiritual which music gives you. So there are a lot of other things going on which aren’t absolutely at the surface, but I do hope people see them. And not necessarily straight away, as well.”

He doesn’t give any more detail than that, but he does say this: “There’s one big thing which people haven’t discovered yet on the album. Let’s just say if people find it, they find it, and if they don’t, they don’t. And remember what Bowie said about not explaining anything.”