"A 100 foot-wide (30 meter), 28-million-pound (12.8-million-kilogram) boulder, was found to have moved 460 feet (140 meters) on #comet 67P/Churyumov-Gerasimenko in the lead up to perihelion in August 2015,"  #space 
<br /><a href='https://images.nasa.gov/details/PIA21565'>https://images.nasa.gov/details/PIA21565</a>