By Claire Corrigan
The Rosetta satellite’s extraordinary 12-year mission came to an end last Thursday, 29 September, as a controlled descent sent the spacecraft into a comet it had been orbiting for two years.
The collision officially brings to an end the craft’s eight-billion kilometre journey and one of the most successful space exploration projects of recent decades.
Kilucan-native Laurence O’Rourke, the Rosetta science operations manager, said there was great excitement as well as some tears at the EPA control room as they watched the crash.
“There was applause, followed by tearful embraces. I was in the briefing room, watching the signal dropping, live. It was a bittersweet moment. You see the pulse go from live to dead. It was sad but when you look at what we did and how much science we achieved, it was well worth it.”
Speaking from the European Space Operation Center in Darmstadt, Germany, the Wesmeath native said that this was the first time the craft had been so close to the surface of the comet. ”We’ve been flying around this comet for two and a half years now, getting closer and closer, but we’ve never flown below a thousand metres and today we did that and the science we got all the way to just a few metres from the surface was really great. We got images up to five to ten metres from the surface and they are gold dust for us.”
Mr O’Rourke has devoted eight years to the project and will continue to interpret data from Rosetta for three years. He is also working on the Plato mission studying exoplanets around other stars and the Asteroid Impact Mission.
Mr. O’Rourke has had a lifelong interest and has been working in the field of space exploration since finishing university in the mid 90s with a BSC degree from NUI Maynooth in physics and maths, and a masters in microelectronic engineering from UCC.
Mr. O’Rourke’s father, Laurence O’Rourke Snr., of Riverstown, Killucan, previously told Topic in 2014 how his son, who is one of eight children, worked on the mission to land a probe – the Philae Lander – on a comet over 500 million kilometres from Earth to obtain samples that will furnish scientists with more information about how planets are formed, since 2004. The probe accompanied the Rosetta spacecraft until it separated to successfully land on a comet.
He also played a major role in the development of a Teamsat satellite which was launched by the Ariane-5 Rocket in the late 90s as well as working on Envisat, the Earth’s observation satellite which launched in 2002 and continuously monitored the Earth for ten years, sending back spectacular images of our planet.
Rosetta hit the comet’s surface at around 11.40am Irish time, but because it is 720 million km from Earth, it took another 40 minutes before the signal of the impact was received.
Although the impact was only at 2km/hr, the craft was not designed to withstand any bumps.
Rosetta will remain crumpled and lifeless on the surface of the comet as the object, a dirty chunk of ice and dust measuring 4.5km across, carries it on repeated circuits of the solar system that may continue for millions of years.
The decision to crash the spacecraft was taken because the comet is now heading so far from the Sun that soon its solar panels will not be able to generate enough power to keep it functioning.
The crash landing is expected to bring a wealth of new information to the European Space Agency before the mission ends.