Once in a blue moon: detection of ‘bluing' during debris transits in the white dwarf WD 1145+017

Israeli Centers for Research Excellence (I-CORE) programme of the Planning and Budgeting Committee (PBC) [1829/12]; Israel Science Foundation (ISF); ISF [648/12]; Science and Technology Facilities Council (STFC); ESO Telescopes at the La Silla Paranal Observatory [097. C-0829, 296. C-5024, 296. C-5014]; NASA