The Stac Fada Member is an intriguing layer of rock in the North West Highlands UNESCO Global Geopark in northern Scotland. This unusual rock layer lies within a sequence of ancient sandstone and mudstone, part of the Torridonian Sandstone that formed more than 1000 million years ago. The layer has been interpreted as a meteorite impact blanket, but the site of the crater is as yet uncertain. Two recent papers argue for two different locations – one sited to the east, near the town of Lairg and the other to the south-west, under what is now the Minch seaway. The controversy is outlined in this recent EOS article ….