2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/4816While symbiotic Miras and planetary nebulae are hard to distinguish by optical spectroscopy, their near infrared colors differ. We propose the near infrared two-color diagram to be an excellent tool to easily distinguish these two classes of objects.4 pages, 2 figures; to appear in "Symbiotic stars probing stellar evolution", Eds. R.L.M. Corradi, J. Mikolajewska, and T.J. Mahoney, ASP conf. series, in pressAstrophysicstext