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Lost landers from HiRISE, The next step
tim53
post Jan 4 2007, 10:18 PM
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I was a bit disappointed to learn how small the Russian landers were. So... given the poor knowledge of their locations, pretty much the only hope of identifying them even IF Hirise hits them, is a parachute that has somehow managed not to be covered with dust in 35 years...

...but it worked for VL-1!

-Tim.
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JonClarke
post Jan 4 2007, 10:28 PM
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QUOTE (tim53 @ Jan 4 2007, 10:18 PM) *
I was a bit disappointed to learn how small the Russian landers were. So... given the poor knowledge of their locations, pretty much the only hope of identifying them even IF Hirise hits them, is a parachute that has somehow managed not to be covered with dust in 35 years...

...but it worked for VL-1!

-Tim.


Mars 2-3 have only been on Mars for 5 years more than Viking, and Mars 6 for 2 years longer. the biggest problem I quess is the certainity of their position.

Jon
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edstrick
post Jan 5 2007, 09:44 AM
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"...NEAR, Hayabusa, Phobos 1&2 and Phobos-Grunt are in a class of their own! 'Featherweight'?"

Near and Hayabusa soft-landed, even though they weren't designed to land and sit still.

The Phobos mission "hopper" was essentially a hard lander, though first-impact speed would have been less than any large body hard lander. I have no idea what the predicted orbital evolution of Phobos 1 would have been after failure and communication loss in phobos-synchronized orbit. It was in an orbit with the same period as Phobos, as I recall, but somewhat elliptical, crossing the moon's orbit ahead or behind (or both) the moon as it orbited Mars. Seems likely to eventually impact Phobos, but I never heard a prediction.

The Pioneer Venus probes were "atmosphere descent probes" with end-of-mission at impact, but one nightside probe survived for a second and the Day probe survived for over an hour before it ---> FRIED <---, so it ended up being an inadvertent hard lander.

"Rough" lander might contrast with "smooth"... uh... I prefer Hard-impact and Soft-landing as the un-contracted ideas behind the terminology. The basic distinction is how "ruggedized" the lander must be and how protected it must be from the rough-and-tumble after uncontrolled hard impact vs. the requirement to remain stable after controlled soft impact.
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ljk4-1
post Jan 5 2007, 04:02 PM
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Though the odds are small until we can actually visit the site in person,
I wonder if the little tethered rover on the Mars 3 lander ever activated?
The tether was apparently 15 meters long.

So perhaps MP and the MERs were not the first to make tread marks on Mars.

http://www.planetary.org/mars/tpr_rover-rus_first-rover.html


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"After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance.
I see that such intercourse long continued would make one thoroughly prosaic, hard,
and coarse. But the longest intercourse with Nature, though in her rudest moods, does
not thus harden and make coarse. A hard, sensible man whom we liken to a rock is
indeed much harder than a rock. From hard, coarse, insensible men with whom I have
no sympathy, I go to commune with the rocks, whose hearts are comparatively soft."

- Henry David Thoreau, November 15, 1853

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nprev
post Jan 6 2007, 01:06 AM
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Man, those were ambitious missions...I sure wish that they had succeeded despite the limitations of their technology & the odds! sad.gif Thanks for the link, ljk4-1.

Given the (apparently still current) thinking that Mars 3 was overturned by winds, I sincerely doubt that the rover could have deployed. Neat thought, though...


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Bob Shaw
post Jan 6 2007, 01:33 AM
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QUOTE (nprev @ Jan 6 2007, 01:06 AM) *
Man, those were ambitious missions...I sure wish that they had succeeded despite the limitations of their technology & the odds! sad.gif Thanks for the link, ljk4-1.

Given the (apparently still current) thinking that Mars 3 was overturned by winds, I sincerely doubt that the rover could have deployed. Neat thought, though...


'Wun away wittle wed wover, wun awwaaaay!'

(crunch)


Bob Shaw


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Remember: Time Flies like the wind - but Fruit Flies like bananas!
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climber
post Jan 6 2007, 02:34 AM
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QUOTE (Bob Shaw @ Jan 4 2007, 01:52 AM) *
I wonder how visible the impact points of the DS2 landers would be?

Obviously, they were pretty small, but they may have kicked off something when they hit.
Bob Shaw

Can't remember if they were 2 or 4! I think 4. Do you know how close of each other they were scheduled to "land"? That has always anoyed me that Both MPL and DS2 failed. Hope it's not the whole package that had trouble way before landing. Anyway, I bet we'll see the probe since MRO's has been so amazing so far. I know I'm an incorigible optimist.


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ljk4-1
post Jan 6 2007, 02:39 AM
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QUOTE (nprev @ Jan 5 2007, 08:06 PM) *
Man, those were ambitious missions...I sure wish that they had succeeded despite the limitations of their technology & the odds! sad.gif Thanks for the link, ljk4-1.

Given the (apparently still current) thinking that Mars 3 was overturned by winds, I sincerely doubt that the rover could have deployed. Neat thought, though...


The more likely answer is that the Mars 3 relay orbiter went out of range for the
lander or there was a communications problem with the orbiter. The whole bit
about the dust storm disrupting things has been overblown, pardon the pun. I
believe that Martian winds are not quite as fierce as on Earth, even the ones that
whipped dust all over Mars in 1971.

Note that the Soviets were quite big on blaming natural causes for the failure of
their space probes, rather than any problems with their Glorious People's Technology.

When Mars 1 stopped transmitting before it reached Mars in 1963 (even though it set a
distance record at the time), the Soviets blamed a meteor hit rather than any problems
with the communications equipment. It was purely a guess on their part, as they had
no way to detect such a strike, especially one that would knock out the probe as a result.

At least we know that Mars 3 is intact on the surface and its parachute and heatshield
are not too far off. As for Mars 2 and 6, I wonder how easily MRO can tell a relatively
recent artificial crater from an older natural one?


--------------------
"After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance.
I see that such intercourse long continued would make one thoroughly prosaic, hard,
and coarse. But the longest intercourse with Nature, though in her rudest moods, does
not thus harden and make coarse. A hard, sensible man whom we liken to a rock is
indeed much harder than a rock. From hard, coarse, insensible men with whom I have
no sympathy, I go to commune with the rocks, whose hearts are comparatively soft."

- Henry David Thoreau, November 15, 1853

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nprev
post Jan 6 2007, 02:49 AM
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Yeah, I'd buy that as a probable alternative explanation.

IIRC, a 200 mph wind on Mars is equivalent in force to something like 25 mph wind on Earth, and the 1971 dust storm was a beaut. Might have been enough to tip a lander during terminal descent (esp. if it also hit a rock! rolleyes.gif ), but we probably won't know until somebody physically stumbles across Mars 3 during an EVA. (In fact, it'll probably be a homesteader circa 2600 AD...lucky guy! biggrin.gif )


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ljk4-1
post Jan 6 2007, 02:52 AM
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QUOTE (nprev @ Jan 5 2007, 09:49 PM) *
Yeah, I'd buy that as a probable alternative explanation.

IIRC, a 200 mph wind on Mars is equivalent in force to something like 25 mph wind on Earth, and the 1971 dust storm was a beaut. Might have been enough to tip a lander during terminal descent (esp. if it also hit a rock! rolleyes.gif ), but we probably won't know until somebody physically stumbles across Mars 3 during an EVA. (In fact, it'll probably be a homesteader circa 2600 AD...lucky guy! biggrin.gif )


The Mars 3 lander transmitted from the planet's surface for 90 seconds, 20 of which
involved returning an image that likely contained nothing but noise.

Would the lander have been able to transmit at all if it had been tipped over? And
would it have survived landing on a rock in the first place? Just imagine if Viking 1
had come down on Big Joe - we never would have found out what happened to
Viking 1, that's what.


--------------------
"After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance.
I see that such intercourse long continued would make one thoroughly prosaic, hard,
and coarse. But the longest intercourse with Nature, though in her rudest moods, does
not thus harden and make coarse. A hard, sensible man whom we liken to a rock is
indeed much harder than a rock. From hard, coarse, insensible men with whom I have
no sympathy, I go to commune with the rocks, whose hearts are comparatively soft."

- Henry David Thoreau, November 15, 1853

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nprev
post Jan 6 2007, 03:16 AM
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QUOTE (ljk4-1 @ Jan 5 2007, 06:52 PM) *
The Mars 3 lander transmitted from the planet's surface for 90 seconds, 20 of which
involved returning an image that likely contained nothing but noise.

Would the lander have been able to transmit at all if it had been tipped over?


Actually, that's an extremely interesting & pertinent question: How 'directional' was the Mars 3 lander antenna for transmission? The answer may go a long way towards resolving this controversy.

Recall also that Oppy's initial landing was confused by multipath reception due to its location within Eagle Crater; they thought it was still bouncing for a LONG time. Was the Mars 3 transmission just maybe a secondary reflection? This might account for the apparently high SNR...


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tedstryk
post Jan 6 2007, 05:12 AM
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QUOTE (ljk4-1 @ Jan 6 2007, 02:52 AM) *
The Mars 3 lander transmitted from the planet's surface for 90 seconds, 20 of which
involved returning an image that likely contained nothing but noise.

Would the lander have been able to transmit at all if it had been tipped over? And
would it have survived landing on a rock in the first place? Just imagine if Viking 1
had come down on Big Joe - we never would have found out what happened to
Viking 1, that's what.

One theory put forth is that the parachute blew over the lander. My hunch is that the transmitter was the problem, since the Mars 2 and 3 orbiters didn't have a fully working transmitter between them.


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As old as Voyage...
post Jan 6 2007, 10:10 AM
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QUOTE (ljk4-1 @ Jan 6 2007, 02:39 AM) *
The more likely answer is that the Mars 3 relay orbiter went out of range for the
lander or there was a communications problem with the orbiter. The whole bit
about the dust storm disrupting things has been overblown, pardon the pun. I
believe that Martian winds are not quite as fierce as on Earth, even the ones that
whipped dust all over Mars in 1971.

Note that the Soviets were quite big on blaming natural causes for the failure of
their space probes, rather than any problems with their Glorious People's Technology.

When Mars 1 stopped transmitting before it reached Mars in 1963 (even though it set a
distance record at the time), the Soviets blamed a meteor hit rather than any problems
with the communications equipment. It was purely a guess on their part, as they had
no way to detect such a strike, especially one that would knock out the probe as a result.

At least we know that Mars 3 is intact on the surface and its parachute and heatshield
are not too far off. As for Mars 2 and 6, I wonder how easily MRO can tell a relatively
recent artificial crater from an older natural one?


So far we've only got a good up close look at one Martian crater definately known to be artificial.

http://antwrp.gsfc.nasa.gov/apod/ap050209.html

Notice how this mini crater displays the dark ejecta seen around far larger and natural recent craters.

I think natural and artificial craters will be indistinguishable unless some debris is still present.


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It's a funny old world - A man's lucky if he gets out of it alive. - W.C. Fields.
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edstrick
post Jan 6 2007, 11:29 AM
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As I think I've pointed out in discussions here a year or two <?> ago, the 1971 global dust storm was in the decaying phase or at most a "plateau" phase at the time of the Mars probe and Mariner arrivals. When the dust fills the atmosphere and pushes tau <opacity, as is currently bothering Spirit rover> to two or more, thermal contrasts in the atmosphere vertically and horizontally are much reduced. The intense variation in solar energy absorption between dusty and non-dusty atmosphere that plays a role in dust storm generation and spreading is gone. There's an increase and change in thermal tides from daytime heating and nighttime cooling of the atmosphere directly, instead of by contact with the heating and cooling surface, but that's generalized, not localized.

It's most unlikely that storm specific winds caused the failure of Mars 3. It's more likely that it hit hard due to imperfect landing system design or poor quality control, or the sorts of problems with the dust-inflated atmosphere that almost caused problems for the MER rovers. It could have had high lateral velocity due to winds and been smacked against a rock..... Whatever. The real problem is that there wasn't any real diagnostic telemetry (so far as we know) reporting on the descent and landing transmitted in real time or after landing. If any was stored on board for eventual relay, I suspect it was rudimentary anyway. There were signals during descent, but I think at a very low data rate.
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tuvas
post Jan 6 2007, 06:57 PM
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QUOTE (As old as Voyager @ Jan 6 2007, 03:10 AM) *
So far we've only got a good up close look at one Martian crater definately known to be artificial.

http://antwrp.gsfc.nasa.gov/apod/ap050209.html

Notice how this mini crater displays the dark ejecta seen around far larger and natural recent craters.

I think natural and artificial craters will be indistinguishable unless some debris is still present.


It's also possible that the dark ejecta could be due to it's recent nature. You can't really rule out anything, at this point in time. Few recent craters have been observed anywhere, and we still have alot to learn about those that we have.
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