The Comet Landing
The Rosetta mission began atop of an Ariane 5G rocket, launched from Europe’s Spaceport in Kourou on March 2, 2004. This ESA-led mission is the first designed to orbit
and land on a comet. It consists of an orbiter,carrying 11 science experiments, and a lander,called ‘Philae’, carrying 10 additional instruments, for the most detailed study of a comet ever attempted
Travelling a distance of 800 million kilometres (500 million miles) from the Sun, the spacecraft took in
an orbit of Jupiter, passing by Earth three times and Mars once, while also flying past two asteroids.
The Philae lander has separated from the Rosetta orbiter, and is now on its way to becoming the first spacecraft to touch down on a comet.
Separation was confirmed at ESA’s Space Operation Centre, ESOC, in Darmstadt, Germany at 09:03 GMT / 10:03 CET. It takes the radio signals from the transmitter on Rosetta 28 minutes and 20 seconds to reach Earth, so separation actually occurred in space at 08:35 GMT / 09:35 CET.
The first signal from Philae is expected in around two hours, when the lander establishes a communication link with Rosetta.Philae cannot send its data to Earth directly – it must do it via Rosetta.
Once the link has been established,the lander will relay via Rosetta a status report of its health, along with the first science data. This will include images taken of the orbiter shortly after separation.
The descent to the surface of Comet 67P/Churyumov–Gerasimenko will take around seven hours, during which the lander will take measurements of the environment around the comet. It will also take images of the final moments of descent.Confirmation of a successful touchdown is expected in a one-hour window centred on 16:02GMT / 17:02CET. The first image from the surface is expected some two hours later. Once on the surface, Philae will transmit data from the surface about the comet’s composition, with the focus on elemental, isotopic, molecular and mineralogical composition of the cometary material,along with the the characterization of physical properties of the surface and subsurface material,the large-scale structure and the magnetic and
plasma environment of the nucleus.However, this exciting science mission is at the mercy of a successful soft landing, the first of its kind.