google - THE moon acquired a new piece of space junk when the dishwasher-sized Smart-1 probe slammed into its surface at two kilometres a second at a site on the moon's Earth-ward side called the Lake of Excellence.
The impact was visible to professional and amateur observers from South Africa to Australia and the US, but not in Europe.
Among the five international radio telescopes involved in observing Smart-1's progress were the Mount Pleasant Observatory of the University of Tasmania, near Hobart, and the CSIRO's Australia Telescope Compact Array at Narrabri.
The European Space Agency's ground station at New Norcia, north of Perth, maintained radio contact with the spacecraft until it crashed.
Astronomers at the Canada-France-Hawaii telescope on Mauna Kea, Hawaii, reported seeing a momentary bright infrared flash as the probe hit the surface on Sunday.
"We know a lot about the moon, but there are things we need to know more precisely if we are to embark on ambitious projects like those planned for the future," said the Smart-1 mission manager, Gerhard Schwehm.
A series of missions will visit the moon in the next few years, culminating in US astronauts returning to the surface for the first time since the Apollo missions, probably around 2020.
Smart-1 (Small Mission for Advanced Research and Technology) is the European Space Agency's first foray to the moon. Launched from French Guiana in September 2003, the 366 kilogram probe has been observing the moon's surface since March 2005 and testing spaceship technology, but mission controllers opted for a spectacular conclusion.
The probe would have hit the moon's surface anyway, but scientists adjusted its trajectory so that the crash could be watched from Earth.
The crash will have gouged a 10-metre wide scar in the moon's surface and scattered debris over about 75 square kilometres. Data on the plume of rock thrown up should tell scientists about the composition of the lunar surface.