19 ms·

Did Philae graze a crater rim during its first bounce?

44 points by kartikkumar 12y ago

xenophonf 12y ago
Considering how many times I've bounced, rolled, and/or crashed a lander in Kerbal Space Program, I am totally impressed that: a - They managed to complete most of the primary science mission! b - They have all of this ancillary data that they think they can use to pinpoint Philae on the comet. c - They think there's a good chance that the probe will start working again. d - They got this far by uploading pre-programmed command sequences to a device around 1600 light-seconds away, so no real-time control whatsoever. That little video game has really increased the amount of respect I have for the scientists and engineers who run these missions. The disappointing state that Philae is currently in is itself an incredible achievement.
- kartikkumar 12y ago
  It really is a fantastic feat of engineering. I've witnessed it at close-range, over the last few months. Over a number of years, I've come across folks working on an array of missions that literally blow my mind (e.g., Cassini-Huygens, New Horizons, MESSENGER). The Mars Curiosity rover is another example of insane engineering. Yes it was over budget, yes there were many technical difficulties (e.g., the wear on the tyres), but landing using the sky-crane absolutely deserves to be heralded as a fantastic feat of engineering. I haven't played KSP myself, but I'm glad to hear that it's providing gameplay that offers insights into the fundamental difficulties of operating in space. I'm going to be leading a project from January to study and simulate on-orbit proximity operations to actively remove discarded rocket bodies in Low-Earth Orbit using a robotic arm. There's so much prep work that goes into missions like these; I wish we scientists & engineers did a better job of communicating the challenges faced and the innovative solutions that are thought up. I have had the pleasure of working with colleagues who amaze me time and again. So now, keep your fingers crossed for Hayabusa [1] in a couple of days. If only we could sustain the excitement, motivation, and sheer wonder that these missions create, the budget for space exploration and planetary science wouldn't have to keep shrinking. [1] http://en.wikipedia.org/wiki/Hayabusa_2 http://en.wikipedia.org/wiki/Hayabusa_2
  - madaxe_again 12y ago
    KSP is excellent. Sure, there's no time lag or relativistic effects, but it is hard, insofar as you have to understand staging (tsiolkovsky!), thrust vectoring, and orbital mechanics. So, so satisfying executing a perfect Hohmann transfer, off the cuff, as precipitation is for suckers. If you enjoy the idea of space travel even slightly, and like the idea of having a semi-earnest crack at it - I can't recommend KSP enough. You get the full joy and frustration of sending a multi-probe mothership to Jupiter, using angular momentum to fling your subassemblies off, only to find that you fitted your landing struts upside down, and having to improv a "landing" using the fuel you'd planned to get home with to touch down. Then explode.
udev 12y ago
I had the same interpretation of the landing, about 10 days ago. "My guess is that Philae landed tumble-weed style, jumping, and rolling until it hit a wall, in this case, the cliff that shadows it." https://news.ycombinator.com/item?id=8619347 https://news.ycombinator.com/item?id=8619347 For me this was the most likley scenario, based on the photos they provided, and the final position.

44 points by kartikkumar 12y ago

Considering how many times I've bounced, rolled, and/or crashed a lander in Kerbal Space Program, I am totally impressed that: a - They managed to complete most of the primary science mission! b - They have all of this ancillary data that they think they can use to pinpoint Philae on the comet. c - They think there's a good chance that the probe will start working again. d - They got this far by uploading pre-programmed command sequences to a device around 1600 light-seconds away, so no real-time control whatsoever. That little video game has really increased the amount of respect I have for the scientists and engineers who run these missions. The disappointing state that Philae is currently in is itself an incredible achievement.

kartikkumar 12y ago
It really is a fantastic feat of engineering. I've witnessed it at close-range, over the last few months. Over a number of years, I've come across folks working on an array of missions that literally blow my mind (e.g., Cassini-Huygens, New Horizons, MESSENGER). The Mars Curiosity rover is another example of insane engineering. Yes it was over budget, yes there were many technical difficulties (e.g., the wear on the tyres), but landing using the sky-crane absolutely deserves to be heralded as a fantastic feat of engineering. I haven't played KSP myself, but I'm glad to hear that it's providing gameplay that offers insights into the fundamental difficulties of operating in space. I'm going to be leading a project from January to study and simulate on-orbit proximity operations to actively remove discarded rocket bodies in Low-Earth Orbit using a robotic arm. There's so much prep work that goes into missions like these; I wish we scientists & engineers did a better job of communicating the challenges faced and the innovative solutions that are thought up. I have had the pleasure of working with colleagues who amaze me time and again. So now, keep your fingers crossed for Hayabusa [1] in a couple of days. If only we could sustain the excitement, motivation, and sheer wonder that these missions create, the budget for space exploration and planetary science wouldn't have to keep shrinking. [1] http://en.wikipedia.org/wiki/Hayabusa_2 http://en.wikipedia.org/wiki/Hayabusa_2
- madaxe_again 12y ago
  KSP is excellent. Sure, there's no time lag or relativistic effects, but it is hard, insofar as you have to understand staging (tsiolkovsky!), thrust vectoring, and orbital mechanics. So, so satisfying executing a perfect Hohmann transfer, off the cuff, as precipitation is for suckers. If you enjoy the idea of space travel even slightly, and like the idea of having a semi-earnest crack at it - I can't recommend KSP enough. You get the full joy and frustration of sending a multi-probe mothership to Jupiter, using angular momentum to fling your subassemblies off, only to find that you fitted your landing struts upside down, and having to improv a "landing" using the fuel you'd planned to get home with to touch down. Then explode.

udev 12y ago

I had the same interpretation of the landing, about 10 days ago. "My guess is that Philae landed tumble-weed style, jumping, and rolling until it hit a wall, in this case, the cliff that shadows it." https://news.ycombinator.com/item?id=8619347 https://news.ycombinator.com/item?id=8619347 For me this was the most likley scenario, based on the photos they provided, and the final position.