Professor Monica Grady has likened the news the Philae lander is awake to a combination of winning the lottery, being a new mother and her wedding day.
The Open University professor, who worked on the project, said: "This is really, really, tremendous news. I cant get across how excited and happy I am."
"We've been waiting since November for this to happen. My reaction when I received the news was is it true? I was trembling."
She said the team would now have to wait for the lander to warm up before continuing with their experiments.
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