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Mars Polar Lander Remains Silent
dante773 writes "ABCNews is reporting the Mars Polar Lander has missed it's primary windows of opprotunity to signal Earth. They still have a few options left to establish contact, though. Hopefully this isn't another failed Mars mission." Other sites carrying regular updates on the Mars Polar Lander that you might to check in with now and then: Offical Mars Polar Lander site; Discovery Channel's continuing coverage.
That's four in a row! The climate surveyor, polar lander and the two impact probes, all shot down by the Martian Air Force.
The question still remains: for what purpose are we exploring Mars? Sure, knowledge about other planets is good, but would Mars be a viable colony, or Yet Anther Dusty Rock? Even the discovery of water molecules in the subsurface of the planet doesn't speak much of its possibility as a future base. I think the best we can hope for out of this mission is just a better understanding of extraterrestrial environments. *sigh*
-- Count Spatula: The Culinary Vampire "...because my cooking sucks."
Here is a page at JPL about what starts to happen since the signal is not being heard.
They are still trying to contact the lander on X-Band, but there is still a UHF radio on board and there is still the matter of redundant radios, plus the little matter that the lander will start swapping out it's own components after six days of not getting commands from Earth. There is still a long way to go before one can start being worried.
So don't give up hope for a few weeks.
-- Erich
Slashdot reader since 1997
It's quite obvious, at least to me, that there are hordes of giant red spacecraft-eating Martian beast gobbling these things up like candy.
If we STOP sending things over there, then maybe we can starve them out. Maybe we should try some sub-atmospheric observance? That way we could keep tabs on them until the died of starvation, then start sending things back over.
Well, sounds good to me at least...
*Drivers Version
***WARNING: FILE NOT FOUND: MPLRLNDR.VXD***
***CANNOT CONTINUE BOOT SEQUENCE***
---Press F1 to continue booting in *SAFE* mode---
Next we'll have to launch a microsoft tech to Mars... grrrrr
*insert pithy sig here*
Apparently the "smaller, cheaper, better" NASA directive is not successful. They should go back to the big and expensive missions. Like Gallileo, Cassini and the ones before them (Chandra, Viking, Voyager, etc.). At least they don't fail(I think from the big ones only Mars Observer failed by exploding before landing). Also, I've noticed that too many Mars missions are failing. The Russians lost all 3 of theirs (one returned some data about Phobos) and NASA is not doing much better. It must be the Martian Air Force as a previous poster said.
Well the do talk about it having a Safe Mode
and we all know what OS has a Safe Mode.
At least the probe seems to be able to do things while in its safe mode, as opposed to Windows Safe Mode.
Rename it Useless Mode I say.
iain
There is a secondary method of communication through Mars Orbiter, that can be made with relatively insignificant effort, after Mars Orbiter finishes communication with two other probes over there right now. This secondary method of communication will relay various signals through the orbiter back to earth, and should such a signal make it, we will likely discover the problem with the primary direct-link comminication method.
Statistically, Americans have been successiful in probing Mars, losing about 1/3rd of their probes into deep space. Of all the (albeit relatively few) Russian attempts, not a single probe made it to Mars and completed it's mission.
Through trial and error, we will eventually come to minimize failures. Automation and higher-level logic/understanding on the parts of the probes is necessary, but perhaps more important than that is the intercommunication between probes, that allows dependence on prior successes to help reduce failures in the future.
I know that a great deal of people love NSAS (myself included) however this would seem to be justification in the minds of washington political leaders to cut funding.
This would be like shooting ducks in a barrel. People in the up and up positions like to have the chance to get returns on investments they make so0 they can get re-elected. I think it may be time to do more advertizing on their rocksts ad such.
Hmm.. a red hat logo is the first thing that the martians see.
Slashdot social engineering at it's finest
This lander consists of 3 landing vehicles. The main landing vehicle (which they tried to communicate with last night) was suppose to make a 'soft touchdown' on the mars south pole. This main lander has a high gain communications sub-system that was suppose to land, and contact earth 20 minutes after touchdown.
After this failed, they sent out a signal to ask the main lander to 'raster' it's high gain across a large area of the sky (sending a signal out, then turn 5 degrees, then send another). sooner or later, in theory, the high gain would eventually align itself with earth, and lock on.
This procedure, so far, did not produce the desired results.
What's more disturbing is, while the main vehicle was descending, it split off 2 small 'impact probes' that were going to impact the mars surface at ballistic speed and dig into the mars soil.
The impact probes have there own UHF communications sub-system and act independently of the main lander. The impact probes (with a much weaker UHF ) relay there signals through the orbiting surveyor that passes overhead every 2 hours.
What's disturbing to me about this development is that even if the main landers high gain has it's own problems, the 2 impact probes act completely independent of the main lander, and should be able to relay there signals home.
What are the odds of both the main lander, and the impact probes having communications problems at the same time? Very slim. This leads me to believe that perhaps there was a problem during decent.
When the mars rover (remember that little dune buggy lookin thing?) descended into the atmosphere of mars, it send out a 'beacon' signal as it descended (allowing everyone here to track it's decent in real time). This decent of the polar lander was done in 'radio silence' thus, we have no telemetry on the decent and landing an any of the 3 landing vehicles.
It's my hope that the dedicated efforts of the many skilled people on the team pays off, and the rest of the mission is nominal.
It is also my hope that (because they are the only ones that have proven results for there work) the mission planers and engineers that did the "Mars Rover" mission get promoted, and there ideas get more funding, attention and authority.
I mean, they're just sitting there enjoying a Martian barbecue and all of a sudden this great bloody thing falls out of the sky and everyone's gotta duck so the primative pink things on the third planet don't know they're around right? So they just start lasering these things before they hit the ground. Problem solved.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Because in the 50s, 60s and 70s, NASA could spend enough money to do these things right.
$150 - $200 million simply may not be enough to guarantee success for a Mars Probe. Engineering for space is enormously complicated and expensive. You need to use much better parts, the system engineering is harder, the software engineer is much, much harder, the testing, the analysis, etc etc are all far beyond what we as a culture seem able (or willing) to pay for.
But these are the years of the Great Navelgazing. Investors will gladly throw billions of dollars at "web startups" that have yet to show a profit, or any significant advancements to technology... but not one penny for the future of the species. In a cultural climate like this, NASA is lucky to get even the few scraps that Congress is begrudgingly willing to throw it.
The fact is that failures like this will continue to happen until something changes.
Colonizing space and neighboring planets is the best way to insure humanity's long-term survival. We'll also have to go interstellar eventually, as even the sun won't live forever.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
The question is which would adapt faster. My guess would be the Mars pathogens.
Well guess this shows you can only strip your budget so much before what you want to achieve can no longer be done. I predict either an electrical malfunction disabled the communications systems or a mechanical malfunction prevented the antenna from deploying. Electrical malfunction is the most likely. Maybe if they had more people on the team or spent more money on hardening these things they would have succeeded. You really need actual humans on the scene to fix these things when they break.
http://www.spaceref.com
License: By reading this you are agreeing that you agree with me.
You're bound for some failures when you launch a piece of tin to another planet. If they can't make contact, I'm sure they'll say that the probe was most likely damaged, or there was an error in the probe's systems, or something like that. There are tons of things that could happen to the probe in the process of reaching Mars that have nothing to do with aliens, monoliths, conspiracies, the KGB, or whatever else some people would have you believe. When there is a successful mission, some people say "It was a conspiracy, they were really taking photos of the Arizona desert!" When there is not a successful mission, the same people say, "It was a conspiracy, they found alien life and now are covering it up!" Seriously, will most people really care if they find any type of alien life forms? If they do, it'll probably be some type of very primitive, simple, single celled organism. If they find evidence of a long dead high technology martian civilization, does it make a difference? I don't see a reason to cover anything up. I mean, if there was a hostile race of Martians bent on taking over earth with their far superior technology, wouldn't they have done so already? What the most concerning thing is that if NASA keeps failing, they might actually start to lose some of their funding, which means we might not actually be able to send a group of humans to Mars anytime soon.
"You spoony bard!" -Tellah
Pick any two.
DNA just wants to be free...
Good reply! I heartily agree! Hear hear!
-AS
-AS
*Pikachu*
If there's no water on Mars, and colonization is the prime goal of our exploration there, then we might as well colonize the moon first. Cheaper, closer, and all the alumninum we want.
What makes the exploration of Mars so interesting is that we don't know that there aren't actually large quantities of water there. We should really know definitively that there is no appreciable water supply there before we discount it as a possible colonization sight.
Aside from colonization, which is one hundred years away at best, there are a multitude of scientifically interesting reasons to explore Mars.
1) What caused the climate of Mars to change? Is Earth in danger of a similar change, and can we be taking steps to prevent that?
2) Did primitive life exist on Mars, and if so, how does it compare to primitive life on Earth?
3) Are there natural resources on Mars worth mining and returning to Earth?
Basically, learning about Mars gives us something to compare our study of Earth against, and may give us a source of resources (and real estate) to help us overcome our rapid depletion of Earth's resources.
You know, Pathfinder. This was the mission that touched down on Mars on July 4, 1997. This was the mission that gave us spectacular panoramic views of the Martian surface, and allowed NASA scientists to actually drive a rover around on the surface of another planet to do remote science. This was a mission that far exceeded its projected life expectancy. Pathfinder will go down in history as one of NASA's most successful missions ever, and it was one of the first Better, Faster, Cheaper missions.
:-)
.. not by a long shot.) These four missions combined have still cost less money than the failed Mars Observer mission.
.. but if it does, let's hope that it doesn't serve to further fuel to fire of the "get rid of NASA" crowd out there. When the U.S. government is spending $350 million on an aircraft carrier that the military doesn't want, it seems kind of petty for these folks to be pointing their fingers at NASA.
By the way, the Pathfinder mission cost less than it did to make a standard Hollywood big-budget blockbuster. I've seen Waterworld. Have you? We put a human-controlled rover on Mars for less money. Which do you think is the bigger waste?
Let's consider the four Better, Faster, Cheaper missions to Mars so far: the Pathfinder, the Global Surveyor, the Climate Orbiter, and the Polar Lander. Of those, two were successful, one was a failure, and one is still in doubt (though as others have said, there is no reason to believe that the Polar Lander has failed yet
NASA's on the right track. Let's just hope that the Polar Lander mission hasn't failed
We're going down, in a spiral to the ground
This seems a little misleading, given that it takes so long (14 mins?) for the radio signals to travel in each direction. So it doesn't seem likely that there'd be quick enough response time for the craft to "align itself" or "lock on" on automatically. More likely, the JPL engineers would wait to hear something during the sweep, determine what the proper orientation was, and then send an explicit command to the lander to orient its antenna with those coordinates. In other words, JPL would know before the lander if and when the sweep crossed Earth's path.
I failed to type out the how this lock-on procedure actually works. It is very time consuming. Usually the high gain will raster from horizon to horizon and keep repeating, until it recieves an explicit command from JPL telling it where earth is.
I just hope the thing isn't upside down in a ditch somewhere. :)
There are only a few places in the solar system that are habitable without major terraforming: the moon, mars, the asteroids and some of the moons of the outer planets. Yes, you'd need a protected environment and wear a spacesuit every time you go out, but you can live that way and there are resources to be utilized.
For the other planets:
Mercury is so close to the sun that it fills most of the sky, a major bummer if you try to live on surface.
Venus is a hot oven full of high pressure poisonous gasses. No landers on it survived very long, despite extreemly rugged construction.
Earth is already taken.
The outer planets are gas giants, except for Pluto which is too far away and *really* cold. Some of the moons might be inhabitable, but traveltimes are impractically long.
Which leaves us the moon, mars and the asteroid belt.
By space standards, Mars is actually quite attractive. It's day is close enough to 24 hours that we'd able to adapt. There is an atmosphere, although an extreemly thin one and mostly CO2. But you can get oxygen out of CO2, compress in to get 3psi pressure and fill a 60s style bubble with it. If you can get a good source of water you have most of the resources to support life in those bubbles. If you have water you can also make methane and oxygen out of water and CO2, which can be used as rocket fuel. Given low gravity and a thin atmosphere getting back into space is relatively easy. Mars is cold, but if you stay in the warmer places it isn't too bad, and the thin atmosphere doesn't cool you down to much - in fact for designers of mars suits getting rid of body heat is a major issue.
The main problem is radiation - no magnetic field like earth to protect anyone on the surface. You'd have to spend most time indoors with a thick roof above your head if you're going to live there permanently.
But living on Mars is definately doable with todays technology, and their are most likely enough resources available to be independent from earth after a while.
It's probably worthwhile too. As somebody put it: the dinosaurs died out because they didn't have a space program.
Cheers!
Comment removed based on user account deletion
Earth : 12:39 p.m. PST on Friday, December 3: OK, we're listening...
Hmm, another conversion error, perhaps? Just kidding...
What if NASA was actually able to communicate with the satellite, just wanting to keep its findings secret. Seems so weird that we've had so many projects fail, maybe they have reasons to suppress any data they get from the Red Planet. Just a thought...
The ABC article:
I'll say. But they won't get too many more chances, if indeed any. There are too many senators and congressmen who see NASA as the ideal whipping boy through whose persecution they can advance their own careers. They won't care if the amount of money wasted is "only" $200m. "Failure after failure" they'll howl. "How much more are we going to stand for?" they'll demand. And no-one will wish to be seen supporting a program that delivers successive failures.
It's not fair, but it looks like NASA's days are numbered. Even by the time I was finishing high school (around 1979) it was trendy to be against spending money on space exploration and for spending it on politically correct causes instead. How much truer is this now?
Without widespread public support the space program is going nowhere. Remember the "smaller, faster, cheaper" philosophy wasn't an end in itself, it was the only possible response to a budget declining year-on-year.
I wish it weren't so. It's a crying shame that there was no proper followup to Apollo. We could've and should've been to Mars and back several times in the last 20 years. Maybe this is it. Maybe this is as far as we'll ever go. doesn't that prospect frighten you? It scares the hell out of me. No space travel=no point in going on, in my book. Might as well head back for the trees.
Consciousness is not what it thinks it is
Thought exists only as an abstraction
Never thought I'd be grateful for the Chinese.
Could this spawn another space race?
Consciousness is not what it thinks it is
Thought exists only as an abstraction
Cameron Park - November 17, 1999 - Given the embarrassing failure of the Mars Climate Orbiter, there is a good deal of nervousness -- both inside and outside the Jet Propulsion Laboratory, that its companion spacecraft, the Mars Polar Lander, might also fail during landing this Dec. 3.
After all, a soft landing is a good deal more complex than a "simple" braking burn to go into orbit around another planet -- and that's not even taking into account the uncertain ruggedness of the landing site terrain itself.
JPL insists that it is taking the advice of the NASA investigative board that looked into the MCO accident, and that -- largely through greatly augmenting the size of the spacecraft's operating team, and particularly its navigation team -- any risk of repeating that appalling incident is over.
But even so, in addition to the standard unknowns of any landing attempt, there are at least three specific problems that have been mentioned over the past week as perhaps endangering MPL. The question is how worrisome are they actually?
(1) On Nov. 7, Keith Cowing's "NASA Watch" Website quoted JPL inside sources as saying that an even more horrific mistake had been made during the assembly of the Lander: the heaters had accidentally been left off the small pyrotechnic charges designed to separate the lander from the "cruise stage" that had supported and guided it during the long trip to Mars, and which was supposed to be separated 5 minutes before the Lander entered the Martian atmosphere!
As a result, these charges would be so cold that they might very well fail to detonate -- so that the Lander, still attached to its cruise stage, would crash uncontrollably onto Mars. The report stated that a JPL "tiger team" had concluded that the decision might well be made to leave the cruise stage attached until entry into the Martian atmosphere had actually begun, in the hope that the heat of air friction would warm the pyrotechnics to the point that they would then fire when commanded -- which, if true, would have been a tremendously risky maneuver.
However, when the MCO Board report was released on Nov. 10, JPL stated that this report was actually just a garbled version of another possible problem that the Board did uncover.
Indeed, Mars Surveyor Program spokeswoman Mary Hardin personally assured SpaceDaily.com on Nov. 15 that this is indeed the case, and that no known problem exists with the pyrotechnic charges.
(2) But what are the real problems that the MCO Investigation Board has turned up?
It involves the main "descent engines" that the lander will use to carry out the final 1800 meters of its final descent to the surface of Mars' after cutting itself free from its parachute, since even a huge chute cannot brake the craft below about 300 km/hour in the thin Martian air. These 12 thrusters burn hydrazine propellant, which is ignited when it contacts a bed of chemical catalyst that causes the hydrazine to break down explosively into ammonia and water vapor.
But the Board raised the possibility that, if the catalyst was chilled below 0 deg C during the long trip to Mars, it might be chemically sluggish in igniting the hydrazine, making the thrusters unreliable.
"...The cold catalyst bed-induced ignition delays, and the resulting irregular pulses on startup, could seriously impact MPL dynamics and potentially the stability of the vehicle during the terminal descent operations, possibly leading to a non-upright touchdown" -- known to the average person as "crash and burn".
Moreover, the MCO Board also noted that if the lander's fuel lines were comparably cold, the hydrazine might freeze solid in them before it even reached the engines.
Having decided that JPL had underestimated these dangers, the MCO Board recommended that the electric heaters for the fuel lines should be turned on earlier than had been planned to ensure that they were properly warm -- and it also recommended that JPL should consider firing the descent thrusters in a series of extremely short bursts during the first few seconds of engine startup, to ensure that the catalyst beds were warm enough to work properly afterwards.
JPL agreed to turn on the fuel line heaters several hours before the lander arrived at Mars, which would raise the temperature of the engines themselves to 8 deg C at the time they were started.
It also stated that its tests showed that the engines' catalyst beds would work properly at temperatures as low as -20 deg C, making those short startup bursts unnecessary -- although it added: "More ground-based test firings are scheduled to better characterize engine performance at various temperatures." At any rate, the odds look good that these particular problems have been dealt with.
(3) However, the Board also expressed another worry. Every previous soft landing that the U.S. or the Soviet Union has ever carried out on the Moon or Mars has involved the use of throttleable rocket engines whose thrust can be controlled over a wide range -- allowing the craft to control its descent speed in response to the data coming in from its radar -- and each engine has also been separately throttleable, allowing the craft to tilt itself in order to cancel out any horizontal drift that the radar detects.
But MPL uses a new "pulse-mode" engine system. Instead of three smoothly throttleable engines, it carries three clusters of four thrusters each whose thrusts are rigidly fixed at 27 kg per thruster -- and it controls its descent rate and its tilt by rapidly flicking the 12 separate thrusters on and off for as little as a small fraction of a second in order to control the craft's overall thrust level.
The Board noted: "This type of powered descent has always been considered to be very difficult and stressing for a planetary exploration soft landing" because of the vibrations it produces -- which is why it has never been used before.
"The concern has been that the feedline hydraulics and water hammer effects could be very complex and interactive. This issue could be further aggravated by fuel slosh, uneven feeding of propellant from the two tanks, and possible center of gravity mismatch on the vehicle... Under extreme worst-case conditions for feedline interactions, it is possible that some thrusters could produce near-zero thrust and some could produce nearly twice the expected thrust when commanded to operate."
JPL had concluded that enough was known by now about these possible problems that computer guidance software could be written that would deal reliably with them -- and since it is much cheaper and easier to develop a fixed-thrust rocket engine than it is to develop and manufacture a new throttleable engine, JPL decided to go with the pulse-mode landing technique this time.
The Board noted: "It was stated many times by the MPL project team during the reviews with the Board, that a vast number of simulations, analyses and rigorous tests were all carefully conducted during the development program to account for all these factors during the propulsive landing maneuver. However, because of the extreme complexity of this landing maneuver, the EDL [Entry-Descent-Landing] team should carefully re-verify that all the above described effects have been accounted for in the terminal maneuver strategies and control laws and the associated software for EDL operations."
Given JPL's blunders in navigating the Mars Climate Orbiter -- and the similar problems the Board uncovered in the management of the MPL, due largely to an inadequate number of personnel and a poorly designed control organization -- this author is not greatly confident that this has been adequately done.
Unfortunately, by this time there isn't much time left to do it thoroughly, or to change the landing software in response. It is therefore reasonable to assume that because of this fundamental problem, there is a distinct element of a risky gamble in the MPL landing, even apart from the unknown terrain features of the exact landing point.
This area of Mars was thought to be one of the smoothest on the planet -- but recent photos by the Mars Global Surveyor's high-resolution telescopic camera have shown that it is somewhat rougher than expected.
Even if MPL does fail, though, at least we'll know why -- right? Wrong. For the first time ever, a spacecraft will have no radio contact of any sort with Earth during its landing sequence -- even the rudimentary kinds of signals that Mars Pathfinder sent immediately on "bounce down" were able to indicate that its landing had been successful.
However, as the landing site is so near Mars' south pole, the Lander's low-gain antenna isn't properly aligned to allow even simple low-power signals to be sent to Earth -- let alone any engineering telemetry on the functioning of the craft's systems.
After separating from its cruise stage, the craft won't reestablish radio contact with Earth until fully 20 minutes after the landing (set for noon Pacific time), at which time it is scheduled to finish pointing its small dish antenna at Earth to allow direct contact.
Later, it will start using its low-gain UHF antenna to communicate larger amounts of data to the Mars Global Surveyor, which will in turn relay it to Earth -- but, for several reasons, MGS can't be used for that purpose until several days after the landing.
If MPL's landing fails, we'll never know why -- whether it's a design flaw in the craft, or simply an unavoidable landing on bad terrain. It will be a replay of the loss of the Mars Observer spacecraft during a brief planned period of radio silence, which forced its accident review board to come up with several possible failure causes and try to guess which was most likely.
Again, this is not reassuring. It's too late to do anything about this with MPL; but for this author it is hoped that by the time of the next landing mission in 2002, NASA will have modified the lander so that it can send engineering data to one of the Mars orbiting spacecraft that are already scheduled to regularly receive data from it after the landing.
In any case, given the number of unknowns in MPL's landing, there will be even more reasons than usual for us to hold our breaths until that confirmatory signal comes through -- or not.
There is limited cooperation between NASA and the USAF in some areas, but the two organizations have very distinct missions.
When the USAF and NASA were jointly funding and cooperating on the Shuttle program, the USAF was not happy about losing control over how their money was being spent and the loss of operational control. The USAF wanted a blue shuttle, and their own launch facility at Vandenberg AFB. This was shot down for budgetary reasons. After the Challenger disaster, the USAF bailed out of the Shuttle program and returned to expendable launch vehicles.
Mea navis aericumbens anguillis abundat
Try Kim Stanley Robinson's Red Mars, Green Mars, and Blue Mars, trilogy. It won many awards for Science fiction, and I would consider it to be not less than superb. Very informative on the technical level, but it makes a valiant attempt to provide a surreal atmosphere to which we apply human politics. This set of books gives me the chills, it inspired me so.