The minor in Astronomy consists of 19 semester hours in astronomy and physics, 10 of which are required: ASTR 1031 , ASTR 3401 , and PHYS 2010 /PHYS 2011 , PHYS 2020 /PHYS 2021  (or PHYS 2110 /PHYS 2111 , PHYS 2120 /PHYS 2121 ). The remaining 9 credits of electives may be chosen from ASTR 1030 , ASTR 2030 , ASTR 2040 , ASTR 3050 , and ASTR 3400 . At least four upper-division hours must be taken at MTSU.