Phobos-Grunt: Failed probe 'falls over Pacific'
Orbital tracking reports suggest Russia's failed Mars probe, Phobos-Grunt, fell back to Earth on Sunday, to be destroyed over the Pacific.
Russian, US and European sources announced the demise of the craft within minutes of each other.
It brings to an end the sorry story of this mission, which promised to return rocky samples from Mars' biggest moon.
Instead, after its launch in November, Phobos-Grunt could not get more than 345km from Earth before stalling.
Once it became clear that controllers could not establish contact with the probe and diagnose its faults, a fiery dive back to Earth was inevitable.
The spacecraft's last orbit took it over Japan, and the Solomon Islands, and to the east of Australia and New Zealand. Conflicting reports then had the final re-entry point across a great swathe of the Southern Ocean. Certainly, it seems Phobos-Grunt was down and destroyed before it could have passed over South America.
The Russian space agency (Roscosmos) had estimated that no more than 200kg of the original 13-tonne launch mass of Phobos-Grunt would survive to the Earth's surface.
"According to information from mission control of the space forces, the fragments of Phobos-Grunt should have fallen into the Pacific Ocean at 1745 GMT," space forces spokesman Alexei Zolotukhin told the Interfax news agency.
The timing would have put the debris fall more than 1,000km west of Chile.
This is the third high-profile spacecraft re-entry in four months, following the return in September of the American UARS satellite and the German Rosat telescope in October. Both fell over the ocean.
With so much of the Earth's surface covered by water, there was every chance Phobos-Grunt would do the same.
The mission was built to land on Phobos, to scoop up rock and bring it back for study in Earth laboratories.
Such a venture would have yielded fascinating new insights into the origin of the 27km-wide object and the planet it circles.
The mission was notable also because China's first Mars satellite, Yinghuo-1, was launched piggy-back on the main Russian spacecraft. It will have been destroyed along with Phobos-Grunt during the fall back to Earth.
The Russians have had a torrid run of space failures recently, leading the head of the country's space agency to wonder even if saboteurs were at work.
Western countries, which use Russian rockets to launch their satellites, are just worried though that some systematic failures have started to appear in what has traditionally been a highly regarded space industry.
With their own opportunity to go to Mars now lost, the Russians may decide to put their future interplanetary efforts into joint ventures with the Americans and the Europeans. The Russians have an offer from the US and Europe to join the ExoMars missions to the Red Planet in 2016 and 2018.
Jonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter