1. ICA, Slovak Academy of Sciences , Dúbravská cesta 9, 845 03 Bratislava , Slovakia
2. Department of Experimental Physics, Faculty of Mathematics, Physics, and Informatics, Comenius University , Mlynská dolina, 842 48 Bratislava , Slovakia
3. Dark Sky Consulting, LLC , PMB 237, 9420 E Golf Links Rd, Ste 108, Tucson, AZ 85730-1317 , USA