Supervised star, galaxy, and QSO classification with sharpened dimensionality reduction M. A. A. Lourens, S. C. Trager, Y. Kim, A. C. Telea and J. B. T. M. Roerdink A&A, 690 (2024) A224 Published online: 11 October 2024 DOI: 10.1051/0004-6361/202450214