DARMSTADT, Germany, Dec. 16 (UPI) -- The European Space Agency's probe Venus Express is no longer in contact with mission control back on Earth. It has used up its fuel supply and is likely to burn up in Venus's lower atmosphere in the coming weeks.
The news marks the end of the Venus Express mission more than nine years after the craft was first launched from the Baikonur Cosmodrome in Kazakhstan.
Over the summer, mission scientists sent the probe into the lower levels of Venus's atmosphere in what was expected to be the final phase of the Venus Express mission -- and the closing chapter of its already longer than expected lifespan. But when data suggested the probe might have a bit more juice, ESA engineers tried to boost the probe back into a more sustainable orbit for some more scientific tasks, with hope of extending the mission into 2015.
Those hopes were dashed in late November, however, when its thrusters finally exhausted all its fuel supply. Full contact was lost on November 28, and while the probe has occasionally re-established contact with mission control in recent weeks, its orbit and power supply is unstable and fading fast.
"The available information provides evidence of the spacecraft losing attitude control most likely due to thrust problems during the raising maneuvers," Patrick Martin, ESA's Venus Express mission manager, said in a press release on Tuesday. "It seems likely, therefore, that Venus Express exhausted its remaining propellant about half way through the planned manoeuvres last month."
Though ESA is saddened by the impending death of its probe, Venus Express leaves behind an impressive scientific legacy.
"During its mission at Venus, the spacecraft provided a comprehensive study of the planet's ionosphere and atmosphere, and has enabled us to draw important conclusions about its surface," explained Hakan Svedhem, ESA's Venus Express project scientist.
The probe's data helped scientists pinpoint Venus's surface temperature at 462 degrees Celsius. The probe's instrumentation was able to study Venus's dense lower atmosphere, a choking concoction of noxious gases, including sulphur dioxide. The probe also detected evidence of surprisingly young lava flows on the planet, suggesting Venus could still be geologically active.
"While the science collection phase of the mission is now complete, the data will keep the scientific community busy for many years to come," Hakan concluded.