         
         var massRange: (min: SolarMass, max: SolarMass) {
             switch self {
-            case .o:
+            case .O:
                 return (min: 16, max: 90)
-            case .b:
+            case .B:
                 return (min: 2.1, max: 16)
-            case .a:
+            case .A:
                 return (min: 1.4, max: 2.1)
-            case .f:
+            case .F:
                 return (min: 1.04, max: 1.4)
-            case .g:
+            case .G:
                 return (min: 0.8, max: 1.04)
-            case .k:
+            case .K:
                 return (min: 0.45, max: 0.8)
-            case .m:
+            case .M:
                 return (min: 0.08, max: 0.45)
             }
         }

        
        var luminosityRange: (min: SolarLuminosity, max: SolarLuminosity) {
            switch self {
            case .o:
                return (min: 30000, max: 1000000)
            case .b:
                return (min: 25, max: 30000)
            case .a:
                return (min: 5, max: 25)
            case .f:
                return (min: 1.5, max: 5)
            case .g:
                return (min: 0.6, max: 1.5)
            case .k:
                return (min: 0.08, max: 0.6)
            case .m:
                return (min: 0.0, max: 0.08)
            }
        }

        
        var radiusRange: (min: SolarRadius, max: SolarRadius) {
            switch self {
            case .O:
                return (min: 6.6, max: 76)
            case .B:
                return (min: 1.8, max: 6.6)
            case .A:
                return (min: 1.4, max: 1.8)
            case .F:
                return (min: 1.15, max: 1.4)
            case .G:
                return (min: 0.96, max: 1.15)
            case .K:
                return (min: 0.7, max: 0.96)
            case .M:
                return (min: 0.33, max: 0.7)
            }
        }
