first_spec_class second_spec_class prob_first_spec_class prob_second_spec_class taxonomy wavelength author ref method S Bus VIS Bus 2002Icar..158..146B SPEC S Tholen VIS Xu 1995Icar..115....1X SPEC S 0.990000 Mahlke VIS Mahlke 2022A&A...665A..26M SPEC S 1.000000 Mahlke VIS Mahlke 2022A&A...665A..26M SPEC