Some elements of the press have had a bit of fun today thanks to a cheeky-looking image from the surface of Mars. It looks for all the world like a robotic rover has carved a picture of a male member with its wheels.

The design was produced from a perfectly normal manouvre carried out by Spirit, one of two Mars Exploration Rovers that landed on the Red Planet in January 2003.

Papers such as the Huffington Pose and The Sun were unable to tell which Mars probe produced the cosmic graffiti. As others have pointed out, it was drawn by Spirit way back in March 2004 and forms part of a panorama made by its cameras.

What has not been highlighted is why the Mars manhood has caught people’s eye now. And it seems the answer is that a prankster with access to a NASA website decided to show it off.

An ageing page about robotics on the Jet Propulsion Laboratory’s website carries a number of links to planetary missions. In most cases, these click through to separate pages describing those missions. But as of tonight,, that labelled “2003 – Mars Exploration Rover”, links instead to a blow-up of the phallic region of Spirit’s panorama.

For the record the original image is known as the Spirit Pancam “Legacy” panorama, acquired on sols 59 to 61 (March 3 to 5, 2004), halfway between the landing site and the rim of Bonneville crater, where the relatively smooth plains become more rocky and rugged. You can see the panorama here.

It spans 360 degrees and consists of images obtained in 78 individual pointings and taken through five Pancam filters at each pointing. Spirit, which landed within Gusev Crater on Mars, became stuck in sand before dying in March 2010. Its twin Opportunity is still active more than nine years after both landed on a scheduled 90-day mission.