Site J: Philae’s primary landing site

by Nur Hussein, staff writer

On August 6, 2014, the Rosetta space probe arrived at the 67P/Churyumov-Gerasimenko comet. Its mission was to study the tiny world, and to that end, it would detach a module called the Philae lander and attempt a landing on the comet itself. The probe, in orbit around the comet, has since analysed the entire comet for possible landing sites on the surface of the duck-shaped object.

Over the weekend, scientists working on the project had a meeting to look at the data and choose a landing site for the lander, which has a mass of 100 kg. Previously, the teams had narrowed potential landing sites to five candidates, named A, B, C, I, and J.

  • A – Located on the “body” of the duck, but with the “head” visible from the landing site
  • B – Within a crater-like structure on the “head”
  • C – A well-illuminated section on the “body”
  • I – A somewhat flat area on the “head”
  • J – Similar to I on the “head,”  but with better illumination

After analyzing the information sent back from the probe, the scientists unanimously voted that the lander plop down on site J, which is located on the “head” of the duck-shaped comet. Site C will be the backup location. The peculiar shape of the comet poses a considerable challenge during the risky maneuver of actually landing a probe on the surface. None of the sites are 100% suitable for guaranteeing the continued correct operation of the robotic probe, but site J was deemed the best choice available. The Philae lander will use harpoons and ice screws to secure itself to the comet, to avoid ricocheting back into space due to the weak gravity on surface.

The lander will conduct in-situ analysis of the comet, studying its composition. Radio waves will be used to study its internal structure. The landing is tentatively scheduled to take place on November 11, 2014, but the actual date will only be confirmed mid-October.


Nur Hussein
Nur Hussein

Nur is a tinkerer of programmable things, an apprentice in an ancient order of technomages. He enjoys fantasy, sci-fi, comic books, and Lego in his spare time. His favourite authors are Asimov and Tolkien. He also loves Celtic and American folk music. You can follow him on twitter: @nurhussein