Rosetta is attempting to become first spacecraft to orbit and land on a comet . `` We are there for over a year to see this complete development to the extent that you may even be able to measure the decrease in the volume of the nucleus ... European Space Agency 's Mars mission has taken Rosetta billions of kilometers across solar system . They hope to learn more about the orbits of comets . The robotic lander Juno is due to touch down in November .
Rosetta is attempting to become first spacecraft to orbit and land on a comet . European Space Agency 's Mars mission has taken Rosetta billions of kilometers across solar system . They hope to learn more about the orbits of comets . The robotic lander Juno is due to touch down in November .