Comet Shoemaker–Levy 9

Comet Shoemaker–Levy 9 (<a href="/facts/Astronomical_naming_conventions/pecagyQS">formally designated</a> D/1993 F2) was a <a href="/facts/Comet/w34utQCd">comet</a> that broke apart in July 1992 and collided with <a href="/facts/Jupiter/95m7XjMT">Jupiter</a> in July 1994, providing the first direct observation of an extraterrestrial <a href="/facts/Collision/0a3WSqod">collision</a> of <a href="/facts/Solar_System/QIcLSazQ">Solar System</a> objects. This generated a large amount of coverage in the popular media, and the comet was closely observed by <a href="/facts/Astronomer/ronF8j4a">astronomers</a> worldwide. The collision provided new information about Jupiter and highlighted its possible role in reducing space debris in the <a href="/facts/Solar_System/QIcLSazQ">inner Solar System</a>.
The comet was discovered by astronomers <a href="/facts/Carolyn_S._Shoemaker/kHSoNJrI">Carolyn</a> and <a href="/facts/Eugene_Merle_Shoemaker/nYNl8t4v">Eugene M. Shoemaker</a>, and <a href="/facts/David_H._Levy/x9JAJAus">David Levy</a> in 1993. Shoemaker–Levy 9 (SL9) had been captured by Jupiter and was orbiting the planet at the time. It was located on the night of March 24 in a photograph taken with the 46 cm (18 in) <a href="/facts/Schmidt_camera/qpNBUu25">Schmidt telescope</a> at the <a href="/facts/Palomar_Observatory/vRLjmDfr">Palomar Observatory</a> in <a href="/facts/California/zLW2vdQJ">California</a>. It was the first active comet observed to be orbiting a planet, and had probably been captured by Jupiter around 20 to 30 years earlier.
Calculations showed that its unusual fragmented form was due to a previous closer approach to Jupiter in July 1992. At that time, the orbit of Shoemaker–Levy 9 passed within Jupiter's <a href="/facts/Roche_limit/ho5gpNr3">Roche limit</a>, and Jupiter's <a href="/facts/Tidal_force/GJgxo7gp">tidal forces</a> had acted to pull the comet apart. The comet was later observed as a series of fragments ranging up to 2 km (1.2 mi) in diameter. These fragments collided with Jupiter's southern hemisphere between July 16 and 22, 1994 at a speed of approximately 60 km/s (37 mi/s) (Jupiter's <a href="/facts/Escape_velocity/bdtme0tx">escape velocity</a>) or 216,000 km/h (134,000 mph). The prominent scars from the impacts were more visible than the <a href="/facts/Great_Red_Spot/8gbPpAJB">Great Red Spot</a> and persisted for many months.

Comet Shoemaker–Levy 9 open-in-new

Comet Shoemaker–Levy 9