Two American robots exploring the surface of Mars are carrying pieces of wreckage from the ruins of the World Trade Centre.
The company who built the drills on the robots' hydraulic arms are based just a few blocks from Ground Zero.
Staff at Honeybee Robotics fled clouds of dust and smoke when the Twin Towers collapsed.
And they decided to pay a "quiet tribute" to the 3000 victims of September 11 by putting debris from the attacks into their design.
Engineers at Honeybee turned two pieces of aluminium from the site into shields to protect the wiring on the drills. Each curved piece is the size of a credit card, and marked with the American flag.
The mayor of New York at the time of the attacks, Rudolph Giuliani, helped Honeybee get hold of the metal they needed for the tribute.
The two Mars rovers, Opportunity and Spirit, landed on the red planet in January 2004. But details of the 9/11 tribute have only just emerged.
The chairman and founder of Honeybee, Stephen Gorevan, said: "It was intended to be a quiet tribute but enough time has passed. We want the families to know."
Friday, 2 June 2006
As seen at Samizdata , this from the Glasgow Daily record: