Subject: Rosetta Mission: A bumpy Landing on 67P for Philae
From: Alex Kemp
Date: Thursday, 13 November 2014 21:54:33 +0000
To: Oliver Kemp, Micaela Kemp, Liisa Kemp, Davin Kemp

The Agilkia (site J) landing site on 67P chosen for Philae

The Philae lander is the size of a washing machine, and has zero thrusters. Essentially, Rosetta aimed itself at the comet & then set Philae free, leaving it to continue until it hit comet 67P, whilst Rosetta itself went back into orbit around the comet. There was one known problem before separation, and 2 problems that turned up after...

Philae has:-

Esa knew before separation that the offset jets were not operational, but decided to go anyway. In fact, after landing it turned out that the harpoons did not work either, and neither did the ice-screws. Whoops.

The result was that Philae bounced. Twice. Esa reckons that Philae bounced off the surface at the chosen landing site a kilometre vertically (the gravity from 67P is very small), and ended up a kilometre away horizontally. Unfortunately, it seems to be in the shadow of a cliff-face, or possibly even at an angle, which will restrict the amount of sunlight that it can get onto it’s solar panels. That will become an issue by next Saturday (15 November). In the meantime, it is busy collecting information, including images.

This next shot is a 2-image mosaic from the CIVA camera, which includes one of the 3 lander-feet in the foreground. Those rocks date back to the beginning of this solar system (4.5 billion years ago):

Where Philae has ended up (CIVA camera; 2-image mosaic)
Alex Kemp