Prognosis Weak for Tonight's Mars Landers

I predict that tonight's Mars landing will be another disaster. Scientists
have publicly stated that sharp rocks can cut the airbags and ruin the
bounce-and-roll landing technique, which is really more of a crash than a
landing. And I am personally skeptical about the ability of such sensitive
equipment to survive such trauma. These landers are fifteen times heavier
than Mars Pathfinder was, and the bounce-and-roll process will traverse
over a kilometer of terrain, allowing plenty of shaking for delicate
systems to break, and unexpected sharp rocks to appear.

I don't feel optimistic about this procedure, and the smartest thing we've
done is to leave ourselves room to figure out what goes wrong, when it
does. Even a backup lander may not be enough to save the missions, since
any design flaws will exist on both devices, and for such precision
craftwork, different assembly flaws may exist on both landers.

"Evil Man" wrote in message
...

I predict that tonight's Mars landing will be another disaster.
Scientists
have publicly stated that sharp rocks can cut the airbags and ruin the
bounce-and-roll landing technique, which is really more of a crash than a
landing. And I am personally skeptical about the ability of such
sensitive
equipment to survive such trauma. These landers are fifteen times heavier
than Mars Pathfinder was, and the bounce-and-roll process will traverse
over a kilometer of terrain, allowing plenty of shaking for delicate
systems to break, and unexpected sharp rocks to appear.

However, the landing bag system is also quite a bit larger than the one used
on Pathfinder. And unlike Beagle 2, the landing system been tested on
airdrops here on Earth, similar to the tests they did on the Pathfinder
lander. You forget that Pathfinder's landing site was heavily strewn with
rocks, including a lot of sharp ones that could have destroyed the landing
bag; yet Pathfinder landed safely. :-)

--
Raymond Chuang
Sacramento, CA USA

"Raymond Chuang" wrote in
hlink.net:

However, the landing bag system is also quite a bit larger than the
one used on Pathfinder. And unlike Beagle 2, the landing system been
tested on airdrops here on Earth, similar to the tests they did on the
Pathfinder lander.

I'm very skeptical about this. Although I may be out of touch, the test
that I saw on TV looked VERY limited, only tossing the lander about five or
ten feet, having it bounce once and land in a net. Bounce-and-roll over a
kilometer looks a lot more violent to me.

Can you list any specifics to suggest that NASA has done a test that
approximates such extreme conditions with any degree of similarity?

You forget that Pathfinder's landing site was
heavily strewn with rocks, including a lot of sharp ones that could
have destroyed the landing bag; yet Pathfinder landed safely. :-)

Pathfinder also weighed a lot less, and therefore had to dissipate a lot
less momentum as it bounced to a halt. Do you know how far it bounced
before it stopped?

I give 'em 80% success chance.



"Evil Man" wrote in message
...

I predict that tonight's Mars landing will be another disaster.
Scientists
have publicly stated that sharp rocks can cut the airbags and ruin the
bounce-and-roll landing technique, which is really more of a crash than a
landing. And I am personally skeptical about the ability of such
sensitive
equipment to survive such trauma. These landers are fifteen times heavier
than Mars Pathfinder was, and the bounce-and-roll process will traverse
over a kilometer of terrain, allowing plenty of shaking for delicate
systems to break, and unexpected sharp rocks to appear.

I don't feel optimistic about this procedure, and the smartest thing we've
done is to leave ourselves room to figure out what goes wrong, when it
does. Even a backup lander may not be enough to save the missions, since
any design flaws will exist on both devices, and for such precision
craftwork, different assembly flaws may exist on both landers.

I predict that tonight's Mars landing will be another disaster.

You predict wrong, Beagle breath!


Patrick

(Patrick) wrote in news:20040104010247.14392.00002076
@mb-m14.aol.com:


I predict that tonight's Mars landing will be another disaster.

You predict wrong, Beagle breath!

The Great Martian Ghoul was too busy feasting on the remains
of Beagle to notice the fresh food supply bouncing down.

Go Spirit! Go Opportunity! Go NASA!!!

--Damon, thinking optimistically

Damon Hill wrote:
The Great Martian Ghoul was too busy feasting on the remains
of Beagle to notice the fresh food supply bouncing down.

Two snacks, every Hohmann arrival opportunity,
that's all it asks.

Just don't ever send just one or two missions per
window again...


-george william herbert

Evil Man wrote in message ...
I predict that tonight's Mars landing will be another disaster.

I trust you're happy to be proved wrong!

All we need now is for Beagle to say Hello (Blur) - then we can rename it Lazarus.


Scientists
have publicly stated that sharp rocks can cut the airbags and ruin the
bounce-and-roll landing technique, which is really more of a crash than a
landing. And I am personally skeptical about the ability of such sensitive
equipment to survive such trauma. These landers are fifteen times heavier
than Mars Pathfinder was, and the bounce-and-roll process will traverse
over a kilometer of terrain, allowing plenty of shaking for delicate
systems to break, and unexpected sharp rocks to appear.

I don't feel optimistic about this procedure, and the smartest thing we've
done is to leave ourselves room to figure out what goes wrong, when it
does. Even a backup lander may not be enough to save the missions, since
any design flaws will exist on both devices, and for such precision
craftwork, different assembly flaws may exist on both landers.

(Alex Terrell) wrote in
om:

Evil Man wrote in message
...
I predict that tonight's Mars landing will be another disaster.

I trust you're happy to be proved wrong!

Although there are still plenty of untested systems that might fail, I have
never been happier to eat my words!

The last twenty years' of spectacular failures have made me cynical about
NASA's abilities, and I have long feared that they are drowning in the
bureaucratic inertia of a huge federal agency. I especially see the space
station as a huge white elephant. Except for giving us experience doing
orbital construction work, it seems like a gigantic solution without a
problem requiring it to exist. But it's a black hole that devours dollars
by the billions.

But what really bummed me out was the loss of Galileo's high bandwidth
antenna. Because of that failure, I believe that the majority of data was
lost that would have gathered by the mission. Excepting that photo of the
asteroid without a star field in the background, I did not see a single
photograph that mission produced. Sci-Am published a very dense article
thoroughly summarizing Galileo's results, but if one picture is worth a
thousand words, the ROI of the lost antenna would have been worth a
thousand equivalents of that dense article. How depressing. AFAIK, there
are no new Jupiter missions under construction, leaving the failure
uncorrected.

And we're down to a fleet of three space shuttles. When the Challenger
exploded, the Ronald Reagan didn't waste a second promising to rebuild it,
even though there was a large federal deficit. But now that Columbia is
gone, deficit spending is larger than ever, and our current Republican has
made no such promise. If we lose one orbiter every fifteen years, that
will eliminate the entire fleet pretty quickly.

And whatever happened to the DS-1 engines and Franklin Chang's throttle-
able plasma drive?

I could go on, but this is already becoming a rant. Suffice to say that
NASA needed a success, and looks like it's here. Whew! I AM SOOO
RELIEVED!


All we need now is for Beagle to say Hello (Blur) - then we can rename
it Lazarus.


Don't get your hopes up, kid. Perhaps we've learned our lessons at Mars.
Now it's the Russian's, Japanese's and European's turns to suffer.

And don't look for the Chinese to put a man on the Moon, either. That's
just big talk, and they'll quickly find out how hard this game is, possibly
by losing some astronauts.

In article , Evil Man wrote:

And we're down to a fleet of three space shuttles. When the Challenger
exploded, the Ronald Reagan didn't waste a second promising to rebuild it,

_The_ Ronald Reagan? I don't think that title has replaced President
yet.


--
"The Union Nationale has brought [Quebec] to the edge of an abyss.
With Social Credit you will take one step forward."

Camil Samson