Rosetta jitters turn to joy for Queen's prof as Philae lander touches down on comet
For a moment it seemed that the whole world held its breath. Then the anxious flight directors glued to their monitors at the European Space Agency (ESA) in Darmstadt, Germany, gave the thumbs-up and everyone was on their feet applauding.
Back in Belfast, the packed John Stewart Bell lecture theatre erupted in cheers and applause as the news came through that the Philae lander descending the 20km from the Rosetta space probe had touched down on the surface of Comet 67P and was already relaying data back to Earth.
And one of the most relieved was Professor Alan Fitzsimmons of Queen's University Belfast, leader of a team that has been studying the comet since before it was even chosen as the target for the Rosetta mission.
"I feel absolutely brilliant - what a relief!" he exclaimed.
Professor Fitzsimmons has now spent more than 10 years collaborating with other European scientists, including graduate students from Queen's, to gather as much information as possible about the comet as Rosetta set off on a 6.4 million kilometre odyssey which included three gravity-assist fly-bys of Earth and one of Mars.
Their job was to plan ahead and figure out what Rosetta was likely to encounter when it reached the comet and they gathered a wealth of information.
"Some things we got right: some things we got completely wrong," he admitted.
"We didn't expect to see boulders.
"We don't know what they're made of - they could be the size of a house but capable of being picked up in your hand," Professor Fitzsimmons said.
"Another thing you don't get from the images is how dark the comet is - it's darker than a lump of coal, because the dust contains a lot of carbon."
Students packed into the lecture theatre were on tenterhooks as they waited for news - scheduled for just after 4pm - about whether Philae had landed successfully.
There was an excited buzz as an image taken by Rosetta of a lonely looking Philae en route to the comet appeared, and the room erupted in cheers when the live stream from ESA headquarters confirmed that the lander had touched down successfully and was relaying data after its seven-hour descent.
"For the current generation of scientists now here, this is like the Apollo missions. It's the first new major exploration of the solar system in their lifetime.
"This is something that they will always remember," Professor Fitzsimmons said.
Space has been a lifelong fascination, he said.
"When I was 11 years old, my friend got a telescope for Christmas and I saw the Moon through it.
"A year later it was given to somebody else, but I was hooked," Professor Fitzsimmons said.
"I just followed my nose and did what I found interesting, which happened to be physics and science.
"I didn't set out to do astrophysics."
Last night Philae had touched down safely but ESA was still waiting for two issues to be resolved - there were some concerns about whether its two harpoons had firmly secured the craft to the surface of Comet 67P, and Rosetta's communications link also appeared to be dropping in and out.
Once these issues are resolved, ESA is hoping to receive the first panoramic images of the surface of the comet. The radar sounder is also due to be deployed to send radar through the nucleus of the comet to get a picture of its internal structure.
These tasks have to be carried out within a window of around 40 hours of battery time, after which Philae will switch to rechargeable batteries. Meanwhile for those QUB students who want to make a career in astrophysics, ESA has a long list of exciting missions in the pipeline, including a craft orbiting Mars and Venus, a planned mission to Jupiter and the Plato mission, which will hunt for planets beyond our solar system.