Impact on Jupiter . ... Credit Copyright: H. Hammel ( MIT ), WFPC2 , HST , NASA Explanation: In 1993, a strange string of comet pieces was discovered near the planet Jupiter . So unusual a sight, Comet Shoemaker-Levy 9 (SL9) quickly became the object of much scientific curiosity. ... The above picture shows the impact site of SL9 's fragment G on Jupiter's cloud-tops . ... Since Jupiter is mostly gas, the comet melted and evaporated before plunging too far into Jupiter's atmosphere . ...