How to map an Exoplanets Rings

In “Astronomers Make a Map of a Super Saturn's Rings,” from the January issue of Scientific American, the Leiden University astronomer Matthew Kenworthy tells the story of discovering a ring system some 200 times larger than Saturn’s around the distant star J1407. Despite its rather large size, across interstellar distances this ring system would normally be totally invisible to us—and in fact Kenworthy and his peers have yet to glimpse J1407b, the giant planet that must be its host. The only reason we know the ring system exists at all is that, by chance, Kenworthy and other researchers happened to see its shadow after it “transited” across the face of its star in 2007.

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