This is pretty cool: it's very complementary to the EHT's ability to directly image a black hole shadow... but the EHT can only resolve the shadow of 2 black ho

This is pretty cool: it's very complementary to the EHT's ability to directly image a black hole shadow... but the EHT can only resolve the shadow of 2 black holes, while this technique could look at many more. I'd advise clicking through to the paper, this is explained pretty well in the introduction.