Rosetta spacecraft headed for comet suicide crash
What you need to know:
Sent by ground controllers on a leisurely, 14-hour freefall, Rosetta launched into a last-gasp spurt of science-gathering on the 19-kilometre (12-mile) journey to its icy comet tomb.
Europe's pioneering spacecraft Rosetta headed for a suicide crash Friday with the comet it has stalked for two years, nearing the end of an audacious quest to unravel the Solar System's mysteries.
Sent by ground controllers on a leisurely, 14-hour freefall, Rosetta launched into a last-gasp spurt of science-gathering on the 19-kilometre (12-mile) journey to its icy comet tomb.
"Next stop #67P!" the European Space Agency (ESA) tweeted, using a shortened version of Comet 67P/Churyumov-Gerasimenko's full name.
It confirmed that the command for Rosetta to exit the galactic wanderer's orbit was received at 2051 GMT Thursday, at a distance of 720 million kilometres (450 million miles) from Earth.
The craft was programmed to terminate its 12-year space odyssey at about 1040 GMT on Friday, joining long-spent robot lander Philae on the comet for a never-ending journey around the Sun.
"We're all very excited," Rosetta project scientist Matt Taylor told AFP at the mission control centre in Darmstadt.
Rosetta's science instruments were primed to sniff the comet's gassy coma, or halo, measure its temperature and gravity, and take pictures from closer than ever before.
"In the final descent, we will get into a region that we have never sampled before. We've never been below two kilometres, and that region is where the coma, the comet atmosphere, becomes alive, it's where it goes from being an ice to a gas," said Taylor.
With the comet zipping through space at a speed of over 14 kilometres (nine miles) per second, Rosetta was programmed to make a "controlled impact" at human walking speed, about 90 cm (35 inches) per second.
Confirmation of the mission's end is expected in Darmstadt around 1120 GMT when Rosetta's signal, which takes 40 minutes to travel, vanishes from ground controllers' computer screens.
"It's mixed emotions," Taylor said of the impending end.
While it will all be over for mission controllers, scientists will be analysing the information gleaned for "years if not decades" to come. AFP
