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For some time, I had difficulty where the above two pictures are located in the picture giving the estimated location. It turns out that the landing position is a little above halfway the red `1' and the red diamond. The `far nop' lays on the red ellipse. You can barely see the two big craters of the landing site picture on the picture showing the estimated landing location. (Picture is the matching part. It surprises me that I have not been able to find a picture like the one used for all estimations with the exact position marked on it. Maybe they did give this during some TV broadcast. But someway I think that most people are not so much interested in this, where I find this kind of things very interesting to know.
I have trouble with locating the last two inside the above picture. It is difficult to estimate the scaling.
Other images of the area:
At the end of the world
We have been at the end of the world. Or at least that was how I
felt about it. Actually, it was not that far, just across the the field
our apartment building is at, a play garden (for children) along
the rail road. The sun was setting, and to me it was feeling as
if we (Annabel and I) were at the end of the world.
If you know this feeling of being at the end of the world, then you will understand it, otherwise not.
The attached description is:
The cluster of orange points on this image represents the uncertainty in our navigation solution that incorporates variations in the conditions during the descent through the atmosphere. This includes changes in the properties of the atmosphere itself such as pressure and density variations and changes in the vehicle aerodynamic characteristics such as lift and drag coefficients. If you imagine an ellipse enclosing the orange collection of points, you can see that it is larger than the red ellipse generated by our mapping of the interplanetary trajectory to the surface. These effects were always there, but they were very small contributors to the overall uncertainty until rather late in the game. It wasn't until we had the last few hours of data before entry that our traditional "navigation" uncertainty became small enough for the descent perturbations to make a significant contribution to the landing uncertainty. (The orange points were computed by Bobby Braun from NASA Langley who participated in the EDL activities here at JPL as the fourth member of our navigation team.)
The green and yellow X's on this image represent two different post-landing solutions for the landing site. The yellow X is the lander location derived from triangulation of features (large rocks, crater rims) visible in the panoramic pictures taken by the lander camera. The green X is a (very) preliminary estimate of the lander location based on tracking data obtained from the lander in the first 2 days after landing. (Yes, we are still getting Doppler and, occasionally, ranging from the lander on the surface of Mars.) The points marked by the X's are roughly 30 km (20 mi) from the target latitude and longitude.
I did not talk to him, but did look at his copy of his latest book. I noticed he had marked broken characters with a green circle and a dash in the border, and typesetting errors with a red circle and a red star on the top of the page. I only saw four type setting errors: 3 times a wrong accent on a Chinese name, and one place where there was a space to much after a comma.
Going through my old belonging always gives me a desire to preserve the past. It is like I want to make an easy accessible archive of all my papers and collections. I was dreaming of putting all my writings on-line. Of course, not right now, but when I am 30 years older. Or at least preserve it for my descendants. Yes, I was really thinking about what they might think when they would search through this archive.
My estimate is that in about 10 years we will have one bookshelves with photo albums, and books full with other papers related to what we as a family produced.
What is the use of all this archiving I wonder.
I also went through some old computer science related technical reports. And I was astonished to see how many dealt with issues that people are working on now. Most of these reports were more than 10 years old. Obvious there has not been much progress, but it worries me, if I see that this is mostly caused by the fact that the wheel is invented over and over again. Really, if you think about it, there has not been much improvement. We are still using the same languages and the same methodologies. O yes, they have different names now, but basically they are the same.
Why, I wonder? Or should we just conclude that we are still in the `craftsman' period of computer science? That we have to wait another 100 years before it has become a real science, like mechanical engineering, and such?
Yes, indeed, I am not going to do a PhD. At first I was disappointed that it did not work out, but now I am satisfied with it. Why did it not work out? That is a good question. To say it simple: it simply did not work out. If you want the hear the whole story, please visited me (or if that is too far, write me an email.)
One thing I know for sure: I do not have the writing abilities which are essential for an academic career nowadays.
(follow-up, about buying the first again)
Just now, I had to think about the glider that my father made for me. I can still remember the shop where we bought it. It was in Utrecht, not far from the main railway station. And then all the hours it took to build this simple plane. But most clearly, I remember the that when we were going to try it out. I was so enthusiastic when I saw it fly that I started to run after it. Faintly I remember that my father called me. His greatest fear became true. In my wild run it landed before my feet, and I stepped on the wing, which broke immediately, as it was made of the very light but also very fragile balsa wood. I cannot remember that he became angry at me, but we walked home silently, both deeply disappointed. He never came to repair the glider, which would not have been an easy task. What ever happened with the plane, I do not know, but I think he silently disposed of it.