42 Isis ( /ˈaɪsɨs/) is a large main-belt asteroid, measuring 100.2km in diameter. It was discovered by N.R. Pogson on May 23, 1856, at Oxford. It was Pogson's first asteroid discovery.
The asteroid's name was chosen by Manuel John Johnson, director of the Radcliffe Observatory in Oxford. Although Isis is the name of an Egyptian goddess, the name was chosen in homage to Pogson's astronomer daughter, (Elizabeth) Isis Pogson. In addition, the Isis is the stretch of the River Thames that runs through Oxford.