These were the Cosmos tie-in reprints of four of his books. I've loved some of the other covers, too (especially the original The Pluto Files), but this cosmic collage effect of these was fun to see in the bookstore back when these came out (around 2013). More publishers should do fun things like this, but sadly a lot of them seem lazy about cover art. Neil's books have consistently been fun. I get nostalgic about reading them, because his writing always gave me warm feelings as a lonely kid into astronomy, like I had an older friend who got it and wanted to talk to me about the wonder of it all on my level as a kid. I still enjoy his writing today, even when I disagree with his opinions, or think that he got something wrong. I've enjoyed many other science writers since then, but none gave me that same friendly, warm, fuzzy feeling that I got from these books and others by Neil.