Author Topic: Contact lost with new Mars probe  (Read 1778 times)

Re: Contact lost with new Mars probe
« Reply #15 on: October 20, 2016, 06:51:20 AM »
Good for you.  Space Shuttle much?  I was on a contractor on a development team that lost a satellite launch (not from Space Shuttle).  We rocket scientists are all powerful, bow down and worship our ... science.  I guess our actual experience (with aerospace in general) isn't consistent ... so reality mustn't be consistent.  All government work, direct or contractor, is dependent on politics.

In other non-space work since, I have seen related government failure ... keep trying to save them from themselves but ... who will save he contracting company from their mistakes?  I will tell you what works, repeated failure, but not giving up, but with the non-PC ability to correct mistakes.  I have seen projects killed, that could have worked, but the management/customer gave up.

96 Flights. I worked STS-26 through STS-122. There is a framed STS-48 mission chart hanging on the wall above my desk as I type. The only satellite I remember us literally losing was the Italian tethered satellite. I've got a piece of the tether hanging on the wall at the office. There was plenty of that to hand out. I think there was 12 or 13 miles of it left on the real when the tether broke.
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Re: Contact lost with new Mars probe
« Reply #16 on: October 20, 2016, 06:52:48 AM »
Sometimes ground control can jigger a response from a lost probe, but might take several months ;-(
Yep, the slow march down every possible path in the software, looking for something that can be fixed. Been there.
We 'new atheists' have a reputation for being militant, but make no mistake  we didn't start this war. If you want to place blame put it on the the religious zealots who have been poisoning the minds of the  young for a long long time."
PZ Myers

Offline Baruch

Re: Contact lost with new Mars probe
« Reply #17 on: October 20, 2016, 07:14:16 AM »
96 Flights. I worked STS-26 through STS-122. There is a framed STS-48 mission chart hanging on the wall above my desk as I type. The only satellite I remember us literally losing was the Italian tethered satellite. I've got a piece of the tether hanging on the wall at the office. There was plenty of that to hand out. I think there was 12 or 13 miles of it left on the real when the tether broke.

Tethered Satellite?  I was asked to be on that ... and I bailed after a few days ... accident waiting to happen unfortunately (on the contractor end).  Don't know about the NASA or EU contribution to failure, except that the project was on hold for a long time, and lost the original contributors (at our end anyway, so failure of continuity).  I will never forgive NASA for the Apollo 1 fire, or the two lost Shuttles ... all preventable.  Better to use robots rather than callously lose astronauts to political calculation.

Usually most people are capable of handing things they have already handled .. until the system decides to take a left turn at Albuquerque.  If they are extrapolating, instead of interpolating, the failure rate is much higher.  They simply don't respect the unknown knowns, let alone the unknown unknowns.  We engineers can be pretty complacent (see famous suspension bridge failure).  But it takes a medical doctor to be really arrogant ;-)

Asking my Mars buddy if he knows what happened with the new probe.  Remember, per Non Disclosure Agreement ... it is possible that except for scuttlebutt, we may never know.
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Re: Contact lost with new Mars probe
« Reply #18 on: October 20, 2016, 07:32:43 AM »
Tethered Satellite?  I was asked to be on that ... and I bailed after a few days ... accident waiting to happen unfortunately (on the contractor end).  Don't know about the NASA or EU contribution to failure, except that the project was on hold for a long time, and lost the original contributors (at our end anyway, so failure of continuity).  I will never forgive NASA for the Apollo 1 fire, or the two lost Shuttles ... all preventable.  Better to use robots rather than callously lose astronauts to political calculation.

Usually most people are capable of handing things they have already handled .. until the system decides to take a left turn at Albuquerque.  If they are extrapolating, instead of interpolating, the failure rate is much higher.  They simply don't respect the unknown knowns, let alone the unknown unknowns.  We engineers can be pretty complacent (see famous suspension bridge failure).  But it takes a medical doctor to be really arrogant ;-)

Asking my Mars buddy if he knows what happened with the new probe.  Remember, per Non Disclosure Agreement ... it is possible that except for scuttlebutt, we may never know.

On the first flight the tether jammed up in the reel after it had only unwound a few feet. I can't remember who was responsible. The re-flight was a freebie for the Italians. NASA let them piggyback on another mission at no charge. Everyone considered that one a success despite losing the satellite. I think it was out 10 or 12 miles and doing everything they thought it would do before the tether broke so they got good data. The failure that time was due to a hole in the insulation on the tether. It arced and blew the cable apart. Once again I don't remember who exactly was at fault because I don't remember if it was a manufacturing flaw or got damaged after it was built.

That one was memorable to me because the Italian PI wouldn't sit in the same room as the Italian hardware guy. They had been friends in college years before when they were working on their PHDs until the hardware guy stole the PI's girlfriend. Decades later he still hadn't gotten over it. We had to set him up with his own conference room so he could attend the mission briefings.
Save a life. Adopt a Greyhound.


Offline Baruch

Re: Contact lost with new Mars probe
« Reply #19 on: October 20, 2016, 07:40:41 AM »
So  ... vendetta?

"On the first flight the tether jammed up in the reel after it had only unwound a few feet." ... that was my exact fear ... that they didn't understand the dynamics when the probe was close to the Shuttle.  I was afraid it would tangle up with the Shuttle, and they wouldn't be able to return to Earth.  The probe itself was probably OK (I think that was the EU part).  It was the integrating contractor's fault, and that is who I worked for.  Of course there is no blame, if not an act of G-d it is an act of Nature ;-)  Basically a failure to understand yo-yo physics (it is more than just centrifugal force).  I have read that the stability of bicycles is still not properly understood (man in loop) in spite of being around for 150 years.  Physicists are arrogant pricks too.
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Re: Contact lost with new Mars probe
« Reply #20 on: October 20, 2016, 09:34:01 AM »
My piece of the tether.



It surprised me when I saw just how small this thing was. It's only about a 1/16" in diameter. That's not very much for something that was supposed to be 20ish miles long.
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Offline Baruch

Re: Contact lost with new Mars probe
« Reply #21 on: October 20, 2016, 07:00:04 PM »
Stiffness ... particularly for the first 100 meters reeled out.  The tensions in the tether overwhelm whatever is happening to the probe in zero G.  Mass ratio only matters if the probe is moving relatively at high velocity (momentum) ... at low velocity a feather can move it.  Of course a spreadsheet could be used to simulate a model of this.

My other problem (as seen later) was that bolt that cut into the tether.  Don't leave any sharp edges in the way, boys!  At least use round heads.
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Offline Mr.Obvious

Re: Contact lost with new Mars probe
« Reply #22 on: October 21, 2016, 06:36:47 AM »
E = Mc²

In the end, we are all standing in the dark,
trying to figure out why we are here.
But let us not choose one direction
without proof of where it is headed.

Check your pocket for matches
so we can observe and learn together
as fast friends and relative idiots.

Offline Baruch

Re: Contact lost with new Mars probe
« Reply #23 on: October 21, 2016, 07:05:50 AM »
Look at the size of those brains!  Typical Progressives ;-)
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Re: Contact lost with new Mars probe
« Reply #24 on: October 21, 2016, 07:20:28 AM »
Yes, Slim Whitman's "Indian Love Call" makes my head explode. What about it?
Save a life. Adopt a Greyhound.


Re: Contact lost with new Mars probe
« Reply #25 on: October 21, 2016, 10:58:00 PM »
The probe most likely went splat.

Re: Contact lost with new Mars probe
« Reply #26 on: October 22, 2016, 07:07:33 AM »
They lost communicate about a minute before landing. Seems possible that everything else went right but it can't phone home.
We 'new atheists' have a reputation for being militant, but make no mistake  we didn't start this war. If you want to place blame put it on the the religious zealots who have been poisoning the minds of the  young for a long long time."
PZ Myers

Offline Cavebear

Re: Contact lost with new Mars probe
« Reply #27 on: October 22, 2016, 07:40:44 AM »
The lander was supposed to work for a few days. The new satellite can stay up there for years. It's all relative.

Mars is sort of a graveyard of landers.  But I'm confused a bit.  I thought we (collectively) had figured out how to use bouncing bubble-wrap (so to speak) and dropped-near-surface techniques.  Did this one try something new or did a previously successful way fail?
Atheist born, atheist bred.  And when I die, atheist dead

Offline Baruch

Re: Contact lost with new Mars probe
« Reply #28 on: October 22, 2016, 08:25:40 AM »
https://en.wikipedia.org/wiki/List_of_missions_to_Mars

Pretty much a crap shoot, but most failures are human induced, sometimes at the drawing board stage.

https://en.wikipedia.org/wiki/Schiaparelli_EDM_lander

The various space agencies have tried various methods, not just the bouncing ball version.

Usual European project ... declared a success in spite of failure ;-)
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Re: Contact lost with new Mars probe
« Reply #29 on: October 22, 2016, 08:33:07 AM »
Mars is sort of a graveyard of landers.  But I'm confused a bit.  I thought we (collectively) had figured out how to use bouncing bubble-wrap (so to speak) and dropped-near-surface techniques.  Did this one try something new or did a previously successful way fail?
Bubble-wrap is okay if you don't want to stick the landing, and your pay load is very rugged. There's a whole lot of bouncing goin' on in that system.

Curiosity used the sky-crane system, it worked once but no guarantees it will work every time.

Schiaparelli just used rockets, rather like trying to soft land a Gemini capsule.
We 'new atheists' have a reputation for being militant, but make no mistake  we didn't start this war. If you want to place blame put it on the the religious zealots who have been poisoning the minds of the  young for a long long time."
PZ Myers