Magellanic clouds: Single measurement throws out everything we thought we knew

Astronomers have measured the 3-D velocities of the Large Magellanic Cloud (shown here) and the Small Magellanic Cloud. They found surprisingly high speeds, which indicates that the Magellanic Clouds are not gravitationally bound to the Milky Way but instead are "just passing through." Credit: Copyright Robert Gendler and Josch Hambsch 2005