Smithsonian.com

Rubber ducks, courtesy of Flickr user Gaetan Lee

Missing: 90 yellow rubber duckies dropped into a moulin (a tubular hole) in a melting Greenland glacier approximately three months ago.

Identifying features: They have “science experiment,” “reward” and the email address of project scientist Alberto Behar of NASA’s Jet Propulsion Laboratory written on them in three languages, including Inuit.

Reward: $100 to the first person who finds a duck.

The bathtub toys were supposed to float along the paths of the melting water under the Jakobshavn Glacier where they were released along with a GPS ice-tracking system (also missing, presumed stuck in the ice). The data from the probe and the locations of the toys’ exit would help scientists better understand what is going on underneath the ice. The Jakobshavn Glacier holds particular interest because nearly 7 percent of the ice coming off Greenland (including, possibly, the iceberg that sank the Titanic) originates with that glacier. (The melting of the Greenland glaciers is a concern because if they all melted, sea level would rise by 23 feet.)

Rubber duckies may seem like an odd choice for studying water movement, but there is a precedent. For years, oceanographer Curtis Ebbesmeyer has been tracking the landings of thousands of rubber ducks and other bath toys were swept overboard and lost in the middle of the Pacific Ocean in 1992 to trace the motion of that ocean’s subtropical and subpolar gyres.