Planets and Moons Universe ID: 13055

A Slowly Spinning Comet

Story by Francis Reddy | Visualizations by Scott Wiessinger Released on December 3, 2018

A rotating green comet that orbits the Sun every 5.4 years dramatically slowed in its spin. Images taken in May 2017 by NASA’s Neil Gehrels Swift Observatory revealed that comet 41P/Tuttle-Giacobini-Kresák, or 41P for short, was spinning three times slower than it was in March 2017, when it was observed by the Discovery Channel Telescope at Lowell Observatory in Arizona. The abrupt slowdown is the most dramatic change in a comet's rotation ever seen. Comets can slow their rotation when ice on their surfaces melt directly to gas, creating jets of gas and dust that act like thrusters. The jets can create a torque, or twisting force, that can either enhance or counter the comet’s rotation. In 41P's case, its small size at less than a mile across meant that more than half its surface area was covered by these jets – leading to a dramatic slowdown from once every 20 hours to once every ~46-60 hours in two months. Watch the video to learn more.

Two weeks before its closest approach to Earth, 41P glides by a galaxy. The green glow is from light emitted by diatomic carbon molecules.

Source Material

For More Information

NASA.gov

Story Credits

Lead Visualizer/Animator:
Scott Wiessinger (USRA)

Lead Producer:
Scott Wiessinger (USRA)

Lead Scientist:
Dennis Bodewits (University of Maryland College Park)

Lead Writer:
Francis Reddy (University of Maryland College Park)

Writer:
Gary Crisostomo (Student, University of Maryland College Park)

Please give credit for this item to:
NASA's Scientific Visualization Studio

Images of green comet: Copyright 2017 by Chris Schur, used with permission

Short URL to share this page:
https://svs.gsfc.nasa.gov/13055

Mission:
Swift

Keywords:
SVS >> HDTV
SVS >> Astrophysics
SVS >> App
NASA Science >> Planets and Moons
NASA Science >> Universe