A spacecraft that has been in hibernation for nearly three years successfully awoke from its deep sleep on Monday, Fox News reported.
The Rosetta, an unmanned space probe controlled by the European Space Agency, was turned on at 5 p.m. EST after being inactive since 2011. Now that it's awake, the Rosetta can begin the final phase of its decade-long mission to land on a comet. The EPA originally shut down the machine in order to save its energy, Fox News reported.
It wasn't until hours later that Rosetta's signal alerting it was awake reached the ESA.
"Rosetta is awake! RT @ESA_Rosetta: "Hello, world!" the ESA tweeted Monday at 1:19 p.m.
If Rosetta reaches its goal, it will become the first spacecraft to land on a comet, a celestial mass of ice and dust. Scientists hope the mission will answer questions about how the solar system and planets were created, Fox News reported. For the most part comets have stayed the same for the last 4.6 billion years, which led scientists to suspect they once supplied planets with water.
"Over the millennia comets have actually affected our evolution," Paolo Ferri, head of the ESA team managing the Rosetta, told Fox News. "There are many theories about comets hitting the Earth and causing global catastrophes. So understanding comets is also important to see in the future what could be done to defend the Earth from comets."
Before the Rosetta sent its signal, ESA scientists had no idea if the probe survived the hibernation, Fox News reported.
"We don't know the status of the spacecraft," Ferri told Fox News. "There is a possibility that we're not going to hear anything. Two-and-a-half years are a long time. We're talking about sophisticated electronics and machines.
"We've taken all possible precautions for this not to happen but of course we cannot exclude that problems may have happened," he said.
The Rosetta is expected to reach the comet 67P/Churyumov-Gerasimenko, in the next few months. Once there, it will fly around the comet before sending a lander, the Philae, onto the comet, Fox News reported. The Philae will then collect samples from the comet and continuously send data back to the ESA until its batteries die.
