After snoozing since 2011, the comet-chasing Rosetta probe awoke today, sending the message "Hello World!" to the European Space Agency just after 1pm EST, according to the AP. The European probe, launched a decade ago, has been in a long hibernation to save power. Now, it's ready for its unprecedented mission to orbit a comet and send a lander to its surface, the BBC reports. The message indicates that the probe has finished its wake-up routine, including warming its navigation instruments and locating Earth.
Rosetta, currently around 500 million miles from Earth near Jupiter's orbit, is due to rendezvous with the comet R67P/Churyumov-Gerasimenko in August. Scientists believe analysis of the comet—believed to be a leftover from the formation of our solar system—will provide vital clues about how the solar system came to be. "It would be really interesting to find out whether the organic chemistry that is relevant for life is there on comets," a Rosetta project manager tells Reuters. (Read more Rosetta stories.)