The European Space Agency鈥檚 Rosetta probe is set to come out of a very deep sleep -- and it made need some encouragement.
The spacecraft is expected to be jolted out of a two-and-a-half-year hibernation on Monday, before undertaking its final mission: chasing down, and landing on, a comet.
The ESA is inviting the public to be part of the next phase of the complex scientific experiment, which has drawn slight comparisons to the fictional Hollywood blockbuster Armageddon, when Bruce Willis leads a team of oil drillers into space to destroy an asteroid threatening the Earth.
The is looking for individuals or groups to record personal messages that will be beamed to the spacecraft. Prizes will be given out for the best "Wake up, Rosetta!" message.
Visitors to Rosetta's can vote on their favourite videos, and the top 10 videos will be transmitted out into the universe and toward Rosetta via one of ESA's deep-space tracking stations in February.
The 鈥榃ake Up Rosetta鈥� campaign runs until Jan. 20, 17:30 GMT.
The spacecraft's internal alarm clock is set for 10:00 GMT Monday. Once Rosetta has warmed itself up, officials say it should re-establish communication with Earth several hours later.
Rosetta was launched in 2004 and has since travelled around the sun five times, picking up energy from Earth and Mars to line it up with its final destination: comet 67P/Churyumov-Gerasimenko.
After a 10-month chase, the spacecraft is expected to rendezvous with the four-kilometre-wide comet in August, before finally landing on its surface in November.
Scientists are hoping Rosetta -- named after the famed stone that proved key in deciphering the Egyptian language of hieroglyphics nearly 200 years ago -- will help researchers 鈥渦nlock the mysteries of how the Solar System evolved鈥� by determining whether comets contributed to the beginning of life on Earth.
For the coldest, loneliest leg of the mission, Rosetta had travelled out toward the orbit of Jupiter and was put into deep-space hibernation.
"It's a very long trip because we had to reach the orbital velocity of the comet," said the ESA鈥檚 Dr. Paolo Ferri.
Ferri said the spacecraft was so far from the sun that scientists couldn't keep it completely active, so it went into its deep sleep in June 2011.
"We had to switch it off," Ferri said, "We've had no contact (for) two-and-a-half years, and Monday, we'll have the first signal since then."
If Rosetta does manage to wake up and complete its mission, it will be become the first spacecraft to land a probe on a comet's surface. It will also be the first mission to escort a comet as it journeys around the sun.
