Norman Lockyer, who in 1906 published the first systematic study of megalithic astronomy, had argued that Bryn Celli Ddu marked the summer solstice. This was ridiculed at the time, but research by Christopher Knight and Robert Lomas in 1997- 98 showed it to be true. Knight and Lomas also claimed that year-round alignments allowed the site to be used as an agricultural calendar. Steve Burrow, curator of Neolithic archaeology at Amgueddfa Cymru (National Museum of Wales), has more recently supported the case for summer solstice alignment. This alignment links Bryn Celli Ddu to a handful of other sites, including Maes Howe, Orkney and Newgrange, Ireland, both of which point to the winter solstice. It has also been suggested that a feature similar to the 'lightbox' at Newgrange may be matched at Bryn Celli Ddu.