Jubilant cheers rang out in Mission Control and across the internet as the European Space Agency confirmed that the Rosetta spacecraft successfully released its lander destined for a nearby comet, 10 years, 8 months and 10 days after the craft lifted off.
The news came shortly after 3 a.m. CST Wednesday morning.
It will take about two hours for the Philae lander to re-establish communication with Mission Control. Confirmation of the washing machine-sized lander’s touchdown on comet 67P/Churyumov–Gerasimenko is expected to come around 10:03 a.m. CST Wednesday morning.
If successful, this mission will mark mankind’s first landing on the surface of a comet.
European Space Agency livestream
Comet 67P/Churyumov–Gerasimenko is a chunk of ice and dust about 4 kilometers wide that was first discovered in 1969.
The spacecraft is named after the Rosetta Stone, an inscribed rock discovered in 1799 that allowed scholars to decipher the hieroglyphics of ancient Egypt. The spacecraft’s lander, Philae, is named after the island where the Rosetta Stone was rediscovered.
The mission is expected to provide a wide range of data that will help scientists better understand the formulations of Earth’s neighborhood some 4600 million years ago, a time when the Solar System consisted not of planets, but of vast swaths of asteroids, comets and spacial debris.
Philae will determine the physical properties of the comet’s surface and subsurface and their chemical, mineralogical and isotopic composition. This will complement the orbiter’s studies of the overall characterisation of the comet’s dynamic properties and surface morphology. Philae may provide the final clues enabling the Rosetta mission to unlock the secrets of how life began on Earth.
ESA announced late Tuesday that the active descent system, which uses thrust to prevent the craft from bouncing off the surface, could not be activated. Instead, the agency is relying on ice screws and a harpoon system to secure the lander.
“The cold gas thruster on top of the lander does not appear to be working so we will have to rely fully on the harpoons at touchdown,” said Stephan Ulamec, Philae Lander Manager at the DLR German Aerospace Center.
Wednesday’s excitement marks a major milestone in a mission that began ten years ago, when Rosetta blasted off on March 2, 2004. The space probe swung past Earth three times and Mars once to gain enough momentum to catch up to the comet.
4 billion miles later, the probe finally arrived at its destination in August.
The spacecraft and the comet are now cruising through the solar system at 41,000 mph, some 311 million miles from Earth. The ESA is relying on NASA’s network of giant radio antennae to stay in touch. It takes 28 minutes and 20 seconds for signals from Rosetta to return to Mission Control – an eternity for those scientists who have invested so much in the mission.
The plan is that Rosetta and Philae will then accompany the comet as it hurtles toward the sun and becomes increasingly active as it heats up. Using 21 different instruments they will collect data that scientists hope will help explain the origins of comets and other celestial bodies.
The European Space Agency says that even if the landing doesn’t succeed, the $1.62 billion mission launched in 2004 won’t be a failure. Rosetta will be able to perform 80 percent of the mission on its own.
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The Associated Press contributed to this report.