Now we know why Philae phouled up comet landing Exactly a year ago, mankind's first ever attempt to land on a comet did not go according to plan - and the European Space Agency (ESA) has just released a report explaining why. The Philae lander was carried for 10 years on the Rosetta probe as it built up speed and approached Comet 67P/Churyumov-Gerasimenko. But when it was …
Too much clubbing, perhaps?
My guess is the explosives. There can't be a lot of data on the longtime effects/processes in explosives in spaaace. Ten years might be even longer than the typical shelf life of the type of explosives used.
"As with all highly energetic substances, explosives are not perfectly stable - their safety and functional features change during ageing. The extent of chemical instability strongly depends on the chemical structure of the explosive - aromatic and aliphatic nitro compounds, secondary nitramines, and organic azides are relatively stable, whereas aliphatic nitrate esters suffer from much lower stability. The rate of ageing of an explosive can be strongly accelerated by incompatibility reactions between the explosive and contact materials." from "Chemical Stability, Compatibility and Shelf Life of Explosives" by Beat Vogelsanger http://www.researchgate.net/publication/233695161_Chemical_Stability_Compatibility_and_Shelf_Life_of_Explosives
"People Get Ready, at the moment I Fly Like an Eagle around Comet 67P/Churyumov-Gerasimenko, listening for Philae, hoping It's Alright. Crazy? Soon, though, A Change is Gonna Come, and instead of Wishing on a Star I'll be setting course for 67P to Lean On Me. Don't Cry, just offer up a Prayer for the Dying as I get ready for the comet's Touch..."
Wrong Seal...?
THE SPACE PEOPLE: Space People read our mail. The Space People think that TV news programs are comedies, and that soap operas are news. The Space People will contact us when they can make money by doing so. The Space People think factories are musical instruments. They sing along with them. Each song lasts from 8 a.m. to 5 p.m. No music on weekends.
(Talking Heads' "Stop Making Sense" liner notes)
I would have though that any adjective in the description of the mission would be best left out. That way the reader can allow credit were it is due. In this case all they got right was funding (possibly.) It was another exploration of failure as far as it goes; which is not as far as it was expected to. Some say.
Isn't 80% a passing grade in Universities (UK) too?
Calling things like this a failure is a complete lack of perspective. They sent a tiny probe on a 10 year journey to a 2.5 mile wide asteroid 490 million KM from Earth, travelling at 84,000mph. Just getting there is an amazing achievement.
The fact they then landed a probe with a broken landing mechanism on it and managed to complete 80% of the planned experiments. Go watch the linked video, look at the abuse that thing took, that it worked at all is unbelievable.
Considering the goal and setbacks, this has been a massive success.
Yes, the original mission did not go as planned - hey we are talking an extremely hostile environment in space.
The mission in my estimation was a success - but of course there will be the obese lounge lizard with a drone who coulda' - woulda' - shoulda' done it better if he'd been asked.
This kind of mission was the stuff of dreams in my boyhood and I'm stoked that I've been alive to see it happen.
Cut the mission operators some slack and if you think you can do better/cheaper then give Kickstarter a try!
As my old Dad would have said - " Well done that man"
My 2c worth - keep the change naysayers.
Indeed. We tend to recall only the successes in space exploration and forget about the mishaps. And this mission, while not 100% perfect, has performed some amazing tricks and delivered interesting science results. Plus the valuable learnings for future attempts.
Hats off to ESA and all other agencies involved (yes, NASA had some instruments on board too)
Actually, the original mission did go as planned - they got Rosetta to catch up with and orbit the comet, photographing it and otherwise analysing the near environment. They also managed to achieve 80% of what they hoped on a never before tried idea that was a secondary, bonus mission, which they said from the beginning (10+ years ago) would be 'nice if it worked'. Well done those engineers and scientists involved in this whole affair. Have several on me.
When just about every landing system fails, you crash into some nook or cranny, or a cranny that's a nook, and remain hidden for over a year, and half your transmitters and receivers are failing, and still deliver 80% of your science goals...
Yeah, have a beer on me.
You sir are talking abject sense have complimentary downvote on me. Well done.
To all those startwreck fans who have personalised landers up their jacksies, may I point out what we really have learned:
If anyone is going to Mars in one of their machines get a note from the doctor telling you you have terminal cancer first. It will be a shame to waste a pilot on another dud.
A "wipe out" would have been the rocket blowing up on the launch pad. A "wipe out" would have been losing contact with the probe before setting it on course to encounter the comet. A "wipe out" would have been the probe being hit and destroyed by a micrometeorite, critical degradation, radiation damage etc on it's 10 year journey to the comet. It would have been failing to achieve orbit around an object with exceptionally low gravity (like "sneeze to achieve escape velocity" low), or scoring a direct hit on it at speed.
Rosetta, the probe, got there without any of these issues.
Philae, in some manner, obviously did degrade or get damaged in the 10 year journey. The operators knew this before they launched it. They could have just not bothered launching it, but having gotten there they might as well try, right? Yes, it didn't land right. Considering they were working with a damaged lander, trying to land it on an unidentified surface (as far as they knew, the surface could have been made of anything from loose gravel to a hard chunk of ice with a veneer of dust) by remote control with significant signal lag (20 minutes? I forget), I wouldn't think of blaming anyone. That it still managed to get 80% of it's workload done even in these conditions is so far beyond amazing that I'm lost for words to describe it. To paraphrase Voltaire, "Perfect is the enemy of progress"
I didn't manage to get 80% of my workload done yesterday...
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