12 Nov 2014

Touchdown! Rosetta’s Philae probe lands on comet

“This is a big step for human civilisation” – the Rosetta mission successfully lands the Philae craft on a comet.

Confirmation of a successful touchdown took place ast 4:08pm GMT, following the separation of Rosetta from its lander, Philae, at 8:35am GMT.

Take an interactive tour of the Rosetta control room

Two hours after Philae separated from Rosetta the European Space Agency’s control room in Darmstadt, Germany, recieved the first signal from the lander. This confirms that data will be received from the lander, such as images.

Because of the length of time it takes for information to pass from Philae to Earth, the landing actually took place at around 3:30pm.

European Space Agency flight director Andrea Accomazzo said: “We can’t be happier than we are now. We have definitely confirmed that the lander is on the surface.”

However it was later confirmed that the lander’s harpoons had failed to fire, meaning the it was not tethered to the surface of the comet, as intended, and may have slowly bounced before landing for a second time.

The radio link was also lost “earlier than expected”, but the scientists running the project said they were confident that Rosetta would be back in contact the next morning.

ESA Director Thomas Reiter said: “Its aim, of course, to unlock the secrets hidden within the icy treasure chest of a 4.6bn years (old) object, to study its make-up and its history. To search for clues as to our own origins.”

Read more: Rosetta and Philae - the most high-profile break-up this year

Eight Rosetta facts

  • Rosetta is named after the Rosetta Stone, which was used to decipher heiroglyphs. Philae is named after an island in the Nile, on which a bilingual obelisk was found, which enabled the heiroglyphs of the Rosetta Stone to be deciphered.
  • The comet is named 67P/Churyumov–Gerasimenko after Klim Ivanovych Churyumov, who discovered the comet in 1969 in a photograph taken Svetlana Ivanovna Gerasimenko.
  • Rosetta has used the gravity of two planets to alter it course to enable it to land on the comet. It has used three planetary flybys of Earth and one of Mars in order to get into the comet’s loop.
  • The comet is two and a half miles in diameter and travels at up to 80,000 miles per hour.
  • Rosetta was the first spacecraft to fly close to Jupiter’s orbit using only solar cells as its main power source.
  • Rosetta’s original target was comet 46P/Wirtanen, but after the initial launch was postponed a new target, Comet 67P, was chosen.
  • The Philae lander is carrying ten scientific instruments, including a drilling system, cameras and spectrometers (measuring properties of light). The Rosetta spacecraft also has scientific instruments on board including very high-resolution cameras, spectrometers and sensors.
  • Philae’s first scientific measurement will be completed in the first two and a half days it is on the comet. However, it could continue its observations, whilst powered by solar cells, for another three months as the comet gets closer to the sun. It is likely that by March 2015 at the latest it will be too hot for the lander to operate.

Later, it emerged that scientists believed the probe could have bounced on impact.

Philae lander manager Dr Stephan Ulamec said: “Maybe today we didn’t just land once; we landed twice.”