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Comment by kartikkumar | Hacker News Reader

Wowoweeeee! This is FANTASTIC news! One of the few times that I have felt like typing in all caps. Incredible news and a testament to the survivability of space hardware. It'll be interesting to see how quickly they can triangulate Philae's true position to better understand the amount of incident light reaching the solar panels. It'll also be interesting to see how much of the payload has survived. Any more data would be of huge scientific value!

Definitely made my day! :)

EDIT: fixed typo

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Yes, amazing news, I am waiting for more data to come in to analyze the comet surface and the condition of the lander. This is obviously one the biggest achievement of modern space missions and ESA.

Here's a little bit more info on the nature of the signal received: http://blogs.esa.int/rosetta/2015/06/14/rosettas-lander-phil...

24W is pretty good. More data on the instrumentation onboard can be found in DLR's fact sheet [1]. So I'm guessing if the hardware has survived, we should see some more science data trickling in. Fingers crossed!

[1] http://www.dlr.de/dlr/Portaldata/1/Resources/documents/Phila...

Yes, the power is pretty good. The temperature is currently told as -35 degree Celsius. I wonder how fast would the temperature variations be, with respect to the movement of the comet and how the lander with adjust to that.

That temperature made me think that humans could survive there if only they were sheltered from the vacuum and radiation of space.

I expected the temperature to be much lower, could this temperature be on the sunny side?

I am also surprised. I guess its because the comet is near perihelion.

Also an impressive achievement on the software side of things - no room for showstopper bugs here! It's not quite as simple as taking it offline, deploying some new code and starting it up again.

Is there any information on the processes used to have such a high level of confidence in the software? Lots of simulation? Relatedly, it might also be interesting to see a list of 'known bugs' and ways they've been worked around.

Hmm, I am not sure if they would have very sophisticated software on the lander, in the way your thinking. I don't think any processing is done on the lander itself. It might be just primarily used as a remote sensing telemetry system. I suppose the lander would have a lot of power management circuits, some control circuits, sensor-actuator circuits, and transmitter-receiver communication circuitry. There would probably be a RTOS for real-time measurement and actuator motion.

Still, I think someone with specific expertise might give a better answer.

> Hmm, I am not sure if they would have very sophisticated software on the lander, in the way your thinking.

I think it's safe to say that's still an order of magnitude more sophisticated than anything I deal with on a daily basis ;)

AFAIK it's similar to the processes for avionics software, but with even more attention to detail. This link came up recently on HN in reference to avionics:

https://en.wikipedia.org/wiki/DO-178B

http://cacm.acm.org/magazines/2014/2/171689-mars-code/abstra... is a good watch.

And you can get a fair bit of insight through many of the videos from Flight Software Workshop - http://flightsoftware.jhuapl.edu/files/_site/workshops/2014/

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