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However putting your suggesting things that I never wrote to one side for a moment - by suggesting that MSL would be a better thing than Phoenix - by saying that for the price of just 2x Phoenix you could have MSL going there instead, by saying that a rover would be better than Phoenix - by suggesting that MSL could and should be going to the Martian polar regions - you are insinuating in the strongest possible way that Phoenix should not fly...it is the only logical assumption based on your argument, if you think something else, then what is your argument about....but hey...at least I didn't put actual words into your mouth that you never spoke like some around here. Bottom line : Phoenix is the best spacecraft - in ATLO or just the drawing board - to investigate the polar regions for several reasons. 1) It has the right instrumentation to answer the questions we need to answer. 2) It has the arm of sufficient size and ability to do the digging required. 3) It is a comparatively cheap lander appropriate for a short life mission that will end with the arrival of the long dark polar winter. 4) The landing site in question does not require mobility as the terrain and science is such that any one spot is good for the science required. MSL would be totally wasted by sending it to polar regions...it would be an utter disgrace, a waste of time, money, and 18 months of the vehicles life. And yes, I do know that MSL is RTG powered and thus doesn't require sunlight to operate - but the requirement of floodlighting on the vehicle, inability to image long rage, and indeed the fact that it would be slowly frosted over during winter whilst wandering around terrain that's the same as the place it landed and the same as anything it could go and visit. http://hiroc.lpl.arizona.edu/images/...P_001337_2480/ - THAT requires a cheaper, short life, volatile focused static lander to ground-truth an orbital observation http://hiroc.lpl.arizona.edu/images/...P_001468_1535/ http://hiroc.lpl.arizona.edu/images/...A_000873_2015/ http://hiroc.lpl.arizona.edu/images/...A_000861_1530/ - THOSE require a highly mobile, geologically equpied long-life rover. Right tool for the right job. Doug |
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Jon |
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Some people just don't realise that Phoenix and MSL are two very different missions, designed for very different goals.
MSL is designed for long range, long duration field geology with a secondary astrobiology mission, and is an expansion of what the MERs have done. Phoenix is designed to test very specific hypotheses about soil physics and chemistry. MSL cannot test them, it does not carry the right payload. Trajectory considerations limit MSL to +/-45 degrees of the equator. MSL would not be able to be sent to the regions that Phoenix can reach (~70-80 degrees N). MSL would be useless through the polar night and would be a wasted mission for much of the time, even if it could be sent to the polar regions Phoenix will cost US$284 million, MSL of the order of US1.2 billion, more than four times as expensive. For the specific questions that Phoenix is designed to answer, it is the superior probe. There were hopes to test the Viking hypotheses about the nature of the martian regolith hypotheses with MPL, Beagle 2, and Mars 96, so there are a lot of people waiting on this. Plus those who had hoped to see their instruments fly on the 2001 lander. Phoenix is an excellen mission that will provide some long overdue information on aspects of the Martian surface, will explore hithertoo unvisited regions of Mars, and so so very cheaply. Jon |
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Because it is mostly already done. I agree that contraption is better that nothing, because now is too late to change anything. Quote:
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Tell me why. It is not possible to build polar version of MSL with instruments similiar to Phoenix suite? Summary: Phoenix is almost complete, so cancelling it now make no sense, is too late. I hope that this mission will be succesful, because Phoenix is better that nothing in 2007. I critique not concept of mission, but lack of mobility. Your biggest argument is that polar plains are all same. Considering that I hear it from Mars enthusiasts, it is very strange argument. So, how I would done it? Many years ago, I would pick different mission for 2007, and after 2009 I would go to polar region with MSL modified to withstand polar enviroment and with Phoenix-like payload. That's all. If you do not like it, well. These are your opinions, like mine. |
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i was thinking the same thing about phoenix, with the rovers moving all over the place and lasting 1000 days longer than expected… it will be a bit of a buzz kill to see the phoenix land and too us non-scientists, it will seem over and done with comparitively.
however, i am excited to see more northern scenes and get something on the ground in a non-mid latitude area.
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Ah and therein lies the issue. Phoenix, like all planetary probes are designed for science, not just for pretty pictures (though I'll agree it's good for PR). Why spend billions more on an MSL-type mission for scientific goals when we have a perfectly capable landing craft for the job? If there is indeed something that requires further investigation (and that's always the case) then a mission can be properly planned in the future.
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"The bread's hollowed out --- the veggies go on forever --- and --- oh my God! --- it's full of meat!" - Maksutov |
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I can not believe you would take MSL away from the terrain for which it is required, and send it to the terrain where it is not - complete and utter madness. Doug |
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Your position might have merit if ESA was just beginning the deep space exploration business, like China and India. However they are not, they have been doing it for more than 20 years. Nor are they neophytes at EDL systems, member countries have been building EDL systems for 40 years. Nor are the technical issues unknown. Thanks to the various successful orbiter and flyby and lander mission it is possible to design precisely for known conditions. [QUOTE=MaDeR;891096Tell me why. [/QUOTE] Why can't MSL cope with the polar night? 1) MSL can't reach the poles. A fact you consistently ignore. To make MSL reach the poles you would need either a bigger earth departure stage - not possible with the selected booster - or to shed mass, you would also need to modify the guidance system. Do0 this and it's no longer MSL 2) MSL is not designed to operate at polar temperatures. You would need to redesign the heating system and power system. Do this and it is no longer MSL, 3) MSL has no night driving system. You could provide it with headlights or an image intensifying system, or thermal IR imaging system to navigate. All of which would cost power and mass. Thus either a bigger rover or unloading some of the payload would be required. Wither way it's no longer MSL Quote:
Why would you want to put the Phoenix instruments onto MSL? They are optimised for a stationary mission, MSL's instruments are optomised for a mobile mission. Why MSL instruments would you leave off for the Phoenix instruments? Quote:
The Viking astrobiology experiments discovered that these areas had identicial peculiar surface properties indicating gasesous exchange with the atmosphere, nutrient binding and oxidation. These were superficially suggestive of biology, but the detailed reaction patterns and the absence of detectable organics meant that the most likelyc ause was unusual surface chemistry involving the presence of reactive clays and super oxides and peroxides. This was done at two widely separated localities with identical results. Combined with data from other missions, most significantly Phobos 2 that the surface dust has the same composition globally (confirmed by later missions), the evidence is that these properties occur right across Mars. These conclusions are dominated our understanding of Martian surface chemistry and physics for 30 years and are long overdue for testing. There have been four previous attempts to test them, all unsuccessful - MPL and Beagle 2 crashed, Mars 96 did not leave LEO and the NASA 2001 lander was cancelled. A detailed physiochemical understanding of what causes the chemical activity of the martian surface will have major implications for instrument slection of future astrobiology missions, how we understand glocal interactions between the atmosphere and the surface, the possibility of present life on Mars, whether Mars could ever have supported life, the liklihood of terrestrial organisms streading on the surface, and what sort of materials should be selected for future probes. Because the suspected properties are globally distributed they need only need to tested in one spot. Since the northern high latitudes of Mars are attractive for many reasons - the presence of near surface water ice, the existance of pressures, temperatures, and humidities high enough on occasion to sustain liquid water - by sending the probe there would kill two birds with one relatively cheap stone. So they only need in situ measurements in one locality to test these hypotheses. What is it about this that you fail to understand? Quote:
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Jon |
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I repeat again: I'm interested in missions involving mobile rover, not any "soo wonderfully diverse deep space" missions. Tell me, how many these mobile rover missions NASA preformed, and how many these mobile rover missions ESA preformed?
This is rubbish. These missions was highly succesful, in spite of all faliures. Especially Galileo. Quote:
This is not important, how it is named. Most important question is different: are changes feasible? I think that you would answer "no". Maybe. Unfoturnately. If "polar version" of MSL (with minior changes only) is not possible, my proposition is not possible. This answers your question? I do not understant that you're so sure about "one locality". I would not be surprised if after Phoenix scientists will propose another mission to pole, but with mobile rover. |
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Look - it's very simple. There is orbital evidence for hydrogen in polar regions. We need a ground truth to find out what form it is. The cheapest and quickest way to do that is to send a comparatively cheap lander up there to have a dig around. That's what we're doing. http://marsoweb.nas.nasa.gov/landing...r_Guide_v2.pdf "As the latitude increases (north or south), several conditions begin to develop that will naturally reduce rover operational efficiency. When the latitude approaches 50-60°N or S, these can in some cases be significant. For example, reduced illumination and the presence of CO2 frost may degrade the quality and interpretability of images used for science or rover operations, such as arm motions or driving. Persistent cold temperatures may reduce the energy available to operate the science instruments. Finally, the short duration or absence of Earth view will impede direct to/from Earth communications." MSL design can do +/- 60 degrees latitude. You couldn't take MSL to the polar regions without a dramatic redesign, without a bigger more expensive LV, without different thermal design, without a means to opperate for many months in total darkness. It wouldn't be MSL any more. It would be complete redesign, perhaps using the MSL landing system of a decent stage and the Skycrane manouver. What you're basically saying is "wouldn't it be nice to send a rover to the north pole of Mars" Yes - it would - it's be great to send 50 MSL's to all over Mars...but that sort of money isn't around - Phoenix will answer the first level questions we want answering for the least money, and the abilites of a rover are far far better sent to the layered outcrops that the 40 or so landing site proposals are all about. Given our current understand of Mars, and the observations taken by MGS, MEX, MRO and MODY, a cheaper static lander to the poles and a mobile vehicle to equatorial layered outcrops is the best next step. |
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Yes, that was a success. Unfoturnately, ESA still have 50% faliure rate involving landing on anything. And that faliure was on Mars, not Titan. So better they be prepared.
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![]() You're convincing, but... what later? When you would send any rover (MSL or no MSL, not important) to polar regions? |
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I would put a dozen of the MSL proposed landing sites higher up a list of "scientifically justifiable" for an MSL type vehicle before the polar regions - both from a position of scientific justification, and operational limitations...you only get six months before the dark comes - better to spend another 150kg on instruments to work the hell out of the reachable terrain, than 150kg putting wheels on the thing to do half a job on a dozen km of similar terrain When you look at the HiRISE images of the Phoenix sites - you look at them....then look at one side, compare it to the other side...there would be no new science to be gained by traversing that. Looks at Gale crater - there would be new scince in moving 1 metre up the outcrop - same at a lot of Meridiani sites, and other sites. These are sites that REQUIRE mobility to do the best science - that is where the money should be spent on wheels. I would rather send a static deep drill than a rover to either pole in actual fact - that would be the next interesting spacecraft in the MSL mass-scale vehicle ( 750kg on the ground ). Land anywhere within a 20km diameter circular landing site - take the remote drilling and analysis hardware that's been on the drawing board for a few years - and do the science with mobility in the vertical, not the horizontal...particularly given that where we see the layers from orbit - we're seing these layers both contaminated by current martian environmental conditions AND often on steep slopes that a rover could not navigate. Better to go 'high' and drill down through those layers ( and oh wow - the science from that would be amazing! - Martain climate records!) In terms of a bigger picture - I don't think were at a point where we are able to send the mass of a payload that would justify mobility (a deep drill type instrument ) AND the means to move it a scientifically significant ( hundreds of km ) distance within one landing. I'd still pick something like a static deep drill over an MSL type vehicle as the next polar mission - simply from a 'best science per $' perspective. Doug |
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Oh, now we renunciate ESA involvement, eh? Well, success have many fathers, faliure no one. Not very convincing...
![]() Mistake of ESA. On their head will be it. Yep, deep drill MUST be immobile. But I think that first kind of this drill will be preformed with human assistance. Looooooooooong time to wait, even if NASA own wet dream of sending humans to Mars fulfill at period mentioned in Bush Vision (chances like snowball in hell - only discovery of life can change that). |
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Galileo was a great mission. But the failure of the high gain antennae had serious implications for data return rate. In particular studies of Jovian atmospheric dynamics were impacted, since the aim of high resolution time lapse imagery of the clouds could not be achieved. Another great mission but one that could have been still greater. Quote:
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To explore the polar environment of Mars would need many missions, including rovers. And ultimately humans. Phoenix is only the start. Its findings will constrain future missions. But its going to be a long time before we get another mission to the polar regions. NASA won't be flying such a mission until the 2013 window. ESA until 2015 or later. Jon |
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So, all in all, this might be something best done with a human crew. The recent JBIS Project Boreas report, about a Mars polar station, explores this (and other matters), and is well worth a read .Quote:
I would like to see a small polar rover to a carefully selected site in the polar layered terrains as the next rover mission after MSL and ExoMars. Sadly this won't be happening until after 2011 for NASA (there isn't a rover in the 2011 Scout proposal list that I am aware of) and after 2020 for ESA (their MSR mission is next cab of the rank after ExoMars, and that won't launch until 2015, at the earliest). But maybe the Japanese, or Chinese, or Indians will be in the Martian exploration game by then. I hope so! Jon |
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You lost. Context. I was talking about ESA experience with mobile rovers here. And their experience in that area is nil.
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![]() Will see. |
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How are they to gain experience except by sending a rover? There is a first time for everyone, even NASA. Before Sojourner, NASA had not done a planetary rover either. Quote:
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Take Giotto, ESA's first deep space mission. Nobody had ever sent a probe to a comett before when the mission was authorised. Not only that, Giotto was going to a very active comet, not a dead hulk, and thus very hazardous. Giooto would make a very close approach, not a distant flyby. Comet Halley is also a very diffucult target in a retrograde, high inclination orbit. All in all a very difficult mission. Giotto proved to be a very successful mission and not onlu survived (with some damage) its encounter with Halley but used a gravity assist (another first for ESA) to visit a second comet (a first for anyone). But by your logic they should have done something simple, like a lunar orbiter. Compared with Huygens, ExoMars is in many respects low risk. It will not be in space as long to get to its target (months not years). It will not haze to face hazards like the ring plane crossing. The atmospheric structure of Mars is much better understood than that of Titan, thanks to seven succesful entries (Mars 3 and 6, the Vikings, Pathfinder, and the MERS. The nature of the martian surface is much better understood than that of Titan (5 sites, thanks to the Vikings, Pathfinder, and the MERs). With Titan they had no idea whether it was doing to be hard or soft, solid or liquid. We even have traficability information from three sites on Mars, thanks to Sojourner and the MERs, plus the geotechnical studies of Viking. If Phoenix succeeds, the ExoMars team will have even more data for planning purposes. In contrast, using your logic, landing on Titan should not have been attempted until much more was known about the conditions. The main risk for ExoMars is its complexity, in complex mission little details might get overlooked that can cause major failures - like the gummed lubricant that nearly doomed Galileo. However ESA has been involved in many highly complex projects, and the instrument packages have been under development for the past 6 years. So has the rover, and with six years to launch, the prototype has already had very successful field trials. As you say, we will see. But the evidence is that ESA have the background knowledge from previous Mars missions and the in-house experience to make this mission a success and it is not (to quote your insulting phrase) a "wet dream". Not that such confidence means assured success, there is always the chance of launch (Mars 96) or Earth departure (CONTOUR) failure or unexpected enviromental conditions (Beagle 2) dooming an otherwise excellent mission. Getting back to the subject of this thread, which is Phoenix, is your silence on the subject and indication that you now recognise that this mission is not (in your original terms) a "toy" but a valid mission that will generate very useful and long awaited data? Jon Last edited by JonClarke; 29-December-2006 at 10:24 PM.. |
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By, for example, sending stationary lander (as simpler, faster, less expensive, not that delicate as mobile rover etc)? But without Pillinger, please. Quote:
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I checked what you said on Wikipedia. First Ranger was in '61, last in '65 (in total nine). Last three (block 3) was full success (launched and impacted as designed). First Surveyor was in '66... So, what you said was false. ![]() Quote:
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Yes. They risked and win. All better for them, but I do not like risking every time and taking harder (and more costly) tasks than neccessary. Quote:
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Most degoratory term what I used was "contraption", not "toy". This is normal on this board to accuse people about things that they never said? This happens again and again... ![]() Yes, I'm convinced. Unfoturnately, not from you. Djellison explained this much better. You have instead false claims and sometime interesting choice of words. |
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You must have been gutted when Richard Cook ( who headed up MPL ) was involved in MER...but...whadda you know.. MER worked! The very best way to recover from a failure is to take the same team - make SOME changes - but leave those with the important experience in place to carry forward.
The mistake Pillinger made was to try and do too much, with too little, in too short a time. He didn't design the Beagle 2 landing system, he's a scientist. The instrumentation he headed up for Beagle 2 was, and remains, exceptional. It forms the basis of the Pasteur payload for Exomars - and again, that is a good think. The experience of building a payload for the surface of Mars is a valuable one - and that experience is valuable in trying again. Meanwhile, ESA have done everything that it should in a prelude to a Mars lander - they did deep space, they did Mars orbit - and now they're trying Mars Landing. To be honest, the content of that Mars Lander doesn't actually matter. You seem to be mixing the difficulty in landing ( which has little relation to the actual payload itself ) and the difficulty in building a functioning rover. As a Brit who pays taxes that fund ESA - I am glad that ESA is doing ExoMars and have as much confidence in the ESA team as I do in the JPL team in such a task. Doug |
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Like I have told you before, I don't play with words. There is a difference between a hard lander probe and an impact one. A hard lander id designed to survive its landing and return data from the target surface. An impact probe returns data up to the moment of impact. Quote:
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Most people would regard any lunar probe as a deep space misson because it is beyond both low and high earth orbit. The propulsive, communication, and tracking issues involved with a lunar mission are essentially the same as those needed for other deep space missions and different to those required for a spacecraft in Earth orbit. Furthermore a lunar orbit mission requires capture by the graviational well of another body and orbit insertion bruns, exactly as required on any other deep space mission. Quote:
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My 0,02 cents... why Phoenix is stationary lander? In NASA? To Mars? In 2007? This contraption should be a great toy to learn landing on Mars for boys and girls from ESA (considering their wet dreams about ExoMars), but why NASA would do that joke? Hello? We have XXI century now... So I have quoted your words exactly. Quote:
Now, since you now recognise the value of Phoenix, I strong suggest you take opinion of ExoMars to this thread if you wish to continue the discussion. Either that or a kind moderator and split off the ExoMars discussion into a new thread, perhaps with a title like: "Is ExoMars a good idea?". That way this thread can stay focussed on Phoenix. Jon Last edited by JonClarke; 29-December-2006 at 11:09 PM.. Reason: additionbal content |
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Too bad for some, the next Mars scout mission has these to choose from, for probable launch 2011:
1) Mars Atmosphere and Volatile Evolution mission, or MAVEN 2) The Great Escape mission The orbiters would study atmosphere, climate, habitability. Anyone see any rovers? Any landers? === Edit: See also topic NASA Selects Proposals for Future Mars Missions and Studies.
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Nice missions, especially regarding habitalibity. I would add to competion this, but ah well. Looks like for this price (scout class mission) no rover is possible.
I would be most interested in sampling upper atmosphere of Mars and return this to Earth, but I don't know if budget of Scout mission allow this... |
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Everything I need to know I learned through Googling. |
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I spoke to Squyres about this very issue at the DPS conference in Sept '05...MER on a Scout budget....and he said no.
ToSeek raises THE main point - Phoenix had about $100M's worth of hand-me-down from the '01 lander - without it, it couldn't be done in a Scout budget. Doug |
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Yeah, and the US has the almighty advantage given they're currently using rovers number 2 and 3 respectively. Get off the high horse, MaDeR, NOBODY has a great deal of experience with rovers. Despite the US being 3 for 3 at the moment, the record of success and failure with Mars related spacecraft means the statistical beast is going to bite us on the butt eventually. Not a matter of if, but when. Rovers are virgin territory for everyone, the US is just off on a good foot. There's nothing to say the ESA can't pull one off when its appropriate to the mission.
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The last time I felt a warm fuzzy feeling, I was informed by my doctor that it was just gas. |
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![]() I see that followers of Spiritual Ways of ESA downplays differences with experience, possibilities and assets (money, money, money) between ESA and NASA. Folks, this is different league and wordplays and prayings will not change this. |
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Phoenix Mars Lander: The Search For A Safe Haven
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Everything I need to know I learned through Googling. |
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The last time I felt a warm fuzzy feeling, I was informed by my doctor that it was just gas. |
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I love pretty pictures of Mars and many people in the world share my opinion. Sending a rover on Mars is no more money than a hollywood blockbuster. So science is not the only valuable payload. And this science is about digging question already asked. A rover can discover new questions. This said , I have nothing against PHOENIX. Seems quite sensible and serious. Last edited by galacsi; 11-January-2007 at 09:05 PM.. |
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