Friday 12 December 2014

some images of Philae - old and recent

a piddling 1½ miles off the predicted splashdown point


I saw the above remark following the Orion test-flight and thought again about the incredible landing of Philae. In the summer, landing site "J" was selected on the smaller lobe of 67P C-G and the field was narrowed down to an ellipse of approx 1 X 1 km square.
This image is from the NavCam on Sep 21:

From September 15:


Look closely at the white boulder:

Above is Wednesday November 12. For comparison, without the "+":
(from Oct 17)
Can you see where I marked the landing?


And so: where is it?
(from Dec 7 NavCam)

I am afraid that this is getting big. However, I want to show you the harpoons
And where they are located under Philae:
And now let us put the pieces together:





And the initial touch down was within 40m of the target selected back in September. And Orion could only do within 3Km?
Philae probably had a measure of luck that the harpoons did not fire - the surface of 67P is much harder than anticipated so a recoil might have been expected. If the retrothruster had cut in Philae might have been a pancake. We may have to wait for a few months to see whether Philae can continue. However, when I asked in 2012 if the lifetime were of the order of 40 hours I was told that if Philae worked 40 hours "they" would be happy. Scientists being scientists - if you give them 40, they will want 40 more. And let us not forget Rosetta with 11 experiments running - planned for at least another 12 months. Much to be thankful for, much to anticipate. wob

5 comments:

  1. Thank for the update.
    Suggestions: Next time split such large entries into 2 or 3 postings.

    ReplyDelete
  2. Not things that go bumb, things that go bounce :-)
    Love,
    Kim /.

    ReplyDelete
  3. Perhaps you might want to adjust your background picture for the blog according to the season. The view of the lake with snow? Now if you only had a webcame capable of showing the current view...:-)

    Love,
    Kim /.

    ReplyDelete
  4. I had actually intended to respond on returning from Germany - but - !
    And I actually like the warmth of the background - it is white to off-white, some would say off-putting, but it is snow. I am overwhelmed by the blog templates and am afraid to try for fear I won't be able to return here.

    ReplyDelete