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*Can't believe there hasn't been a thread established for this topic. I used the Search feature twice -- all forums, first for this year and then for the entire history of the boards.
Maybe it's been mentioned once or twice in another thread, but time to start one devoted to it:
http://jagor.srce.hr/damirspace/phoenix.htm]Originally built to fly as part of 2001 MSP
http://phoenix.lpl.arizona.edu/]NASA site
This complement of spacecraft and payload is ideally suited to perform a scientific analysis of the Martian arctic soils for clues to its geologic history and potential for biology.
http://planetary.chem.tufts.edu/Phoenix/]Another really good site -- packed with info
--Cindy
We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...
--John Sladek (The New Apocrypha)
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*This may be especially good news for some folks here (especially the Viking mention):
Continuing the Viking quest, but in an environment known to be water-rich , Phoenix will search for signatures of past life that may be found in disequilibrium isotopic ratios and fossil microbe communities.
http://planetary.chem.tufts.edu/Phoenix … tm]Landing site
--Cindy
We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...
--John Sladek (The New Apocrypha)
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Ya I had found a few articles that talk of all three probes being sent to mars stating in 2005, then 2007 and finally in 2009 but not much seperately.
from decontamination article:
Then, in 2007, comes the Phoenix, which will explore the polar ice caps and drill for samples, according to Karen Buxbaum, Mars program planetary projection manager from the Jet Propulsion Laboratory. The ice caps are believed to contain organic compounds, which, in turn, could help answer the question of whether life existed--or exists--on Mars.
Edit:[url=http://www.marsnews.com/missions/phoenix/]
here is a link to all news articles from the part year or so[/url]
QUICK FACTS
Launch: October 2007
Landing: late 2008
Science instruments:
Mars Descent Imager (MARDI)
Stereo Surface Imager (SSI)
Thermal Evolved Gas Analyzer (TEGA)
Mars Environmental Compatibility Assessment (MECA)
Meteorology Suite (MET)
Robot Arm and Camera
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phoenix site launched:
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phoenix site launched:
Thanks for the link.
Scheduled to last for three months, working in the summer of 2008 - looks like a good plan to me
Graeme
There was a young lady named Bright.
Whose speed was far faster than light;
She set out one day
in a relative way
And returned on the previous night.
--Arthur Buller--
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A few more bits from the website...
Launch scheduled August 2007 on a Boeing Delta II from Kennedy Space Center
It will then cruise for 10 months to Mars
In May 2008 it will start its entry into the Martian atmosphere, descent and then landing phase. This consists of - aeroshell braking, parachute descent phase, and its final touchdown will by controlled with thrusters.
On the surface its expected to last for 3 months to carry out its primary operations, there is of course a extended operations phase if all goes well which is marked up to last 2 months.
There will be no long term extension as winter will cover the lander in dry ice.
The two stated science goals for the mission are...
1. to study the history of water near Mars' north pole.
2. to search the soil for life signatures.
Above info from the mission overview pdf available http://phoenix.lpl.arizona.edu/overview … t.pdf]here
Graeme
There was a young lady named Bright.
Whose speed was far faster than light;
She set out one day
in a relative way
And returned on the previous night.
--Arthur Buller--
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Looks like Dan Maas has been comissioned to re-do the '01 lander anim for the new instrument package GOOD NEWS
Doug
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The mission profile sounds like Phoenix will be Mars Polar Lander redux, albeit at the north pole instead of the south one. I hope the outcome is more successful.
I still think it's worthwhile to send Mars Recon Orbiter searching for MPL to see what condition it's in. The NASA people believe that it was killed by the shock of deploying the landing gear, while the imagery community thinks it landed intact and had a communications problem. Whichever is the case, it's is an important fix that must be made before Phoenix launches.
Who needs Michael Griffin when you can have Peter Griffin? Catch "Family Guy" Sunday nights on FOX.
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Well - regardless of any ACTUAL reason - the coding error that the review board found ( the deployment of the landing pads triggering the touchdown sensors and thus prematurely setting a software switch to turn off the thrusters ) would have killed the lander anyway So - if it was a communications error, fine, but it was a communications error from a lump of debris that hit the ground at great speed after failing to use it's thrusters to land.
Doug
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This spacecraft was originally to have been the 2002 Mars Surveyor Lander.
The Landers of the Mars Surveyor Program were all of the same basic size, shape, design, and mission operations. They were part of NASA chief (at the time) Dan Goldin’s “Better, Faster, Cheaper” philosophy that he and his people were imposing on the agency. Only one Lander from the Mars Surveyor program was ever launched – renamed the Mars Polar Landersome months prior to its launch. It crashed while attempting to land on Mars. The loss of this and another Mars Surveyor spacecraft (the Mars Climate Orbiter) at approximately the same time precipitated a program-wide review. In a nutshell, the review determined that the specific cause of failure could not be determined, but as djellison has mentioned in the prior post, there were very serious flaws in the spacecraft’s terminal descent process as it was designed. What the board also found though, was that the “better, faster, cheaper” mantra that the Mars Surveyor program was modeled after was itself very seriously flawed – and was the overriding root cause for the flawed terminal descent process in the first place. While touted at the time as a way of sending more spacecraft to the planets by making them less expensive, the "better, faster, cheaper" idea was taken way too far because of a zeal at the top at NASA to cut budgets. (Dan Goldin at the time would brag about his asking to have the NASA budget CUT, as opposed to increased. He was quoted as saying that if he has been hired a few years earlier than he was, he would have loved to have cancelled Cassini – a program that he despised. He described it as an expensive dinosaur that he dubbed “Battlestar Galactica”).
Specifically, the Mars Surveyor failure board found that the program staff was understaffed in order to cut costs, and resultantly overworked. The vehicle itself had many areas of little or no redundancy in order to cut costs. A single point failure on the vehicle at many junctures could scuttle the mission. Equipment was not tested as rigorously as in the past to save money. Basically the whole thing was done way too much on the cheap.
The whole lander portion of the Mars Surveyor program was seen as so suspect that the program in it’s current form at the time was cancelled. This was despite the fact that another flight model had been assembled and was being prepared for launch. It was instead put into storage. This is the vehicle that will be taken out of storage, partially rebuilt to fix the flaws where possible, mission operations redesigned, and re-christened as The Mars Phoenix Lander. This is also where the vehicle gets its name – a new bird born out of the ashes of its prior death.
Not all was lost in the “better, faster, cheaper” debacle however. One lesson learned was just how far to the bone one could cut with planetary exploration before a mission was too much of a risk. Systems miniaturization and standardization were greatly advanced in efforts to save vehicle weight. Standardization of spacecraft operations were developed.
Ulitmatly, a more appropriate medium between “flagship class” planetary missions such as Cassini and “cut to the bone” missions such as Mars Polar Lander was developed. They were called the Mars Exploration Rover. They seem to work pretty well.
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Hi GregM and welcome to New Mars!
That was a marvellous recapping of the history of the Phoenix lander, which I enjoyed reading.
:up:
[I'm probably dreaming but was Goldin's idea ever described as 'smaller, faster, cheaper'?
I seem to remember reading it as that somewhere many years ago(?). It's probably a better description of the concept and precludes the standard criticism of 'better, faster, cheaper', which was "Pick any two!". ]
The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down. - Rita Rudner
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Part of the main stream of the Idea of cheaper, better and faster got lost in each facilities efforts to give probes to the various sites that where on the list to explore.
The idea of making say a lander for mars work as a lander say for Titan was more in line with one concept of duplication. If all the same instruments are part of the landers concepts for either locations are the same then why go though a new design concept? This was what IMO he was striving for. It is cheaper to make 2 of something usually since all the tooling and such are already in use.
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http://www.universetoday.com/am/publish … 5]*Digging on Mars won't be easy
*Mentions Phoenix lander in the article and also a different (future) mission, but will place this here. Phoenix will assist in research in this regard, as apparently it will dig trenches 20 inches deep.
Discusses granular physics. "One moment they behave like solids, the next like liquids." Wishes to anticipate answers to questions such as how steep the sides of a Martian trench can be and remain stable without caving in.
Interesting, unfamiliar (to me anyway) stuff.
--Cindy
P.S.: Also mentions hoppers (their tendency to jam, etc.) and the headaches around keeping mission equipment operative throughout the seasonal dust storms (well...won't the MERs already help in figuring that out?).
::EDIT:: Well, here's a way they've already assisted:
As early as the 1960s when scientists were first studying possible solar-powered rovers for negotiating loose sands on the Moon and other planets, they calculated "that the maximum viable continuous pressure for rolling contact pressure over Martian soils is only 0.2 pounds per square inch (psi)," especially when traveling up or down slopes. This low figure has been confirmed by the behavior of Spirit and Opportunity.
::EDIT 2:: Didn't know this:
The problem is, even here on Earth "industrial plants don't work very well because we don't understand equations for granular materials as well as we understand the equations for liquids and gases," says James T. Jenkins, professor of theoretical and applied mechanics at Cornell University in Ithaca, N.Y. "That's why coal-fired power plants operate at low efficiencies and have higher failure rates compared to liquid-fuel or gas-fired power plants."
Wow.
We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...
--John Sladek (The New Apocrypha)
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Not to mention we will likely find that the Martian fines may be charged and as such "sticky"
Still it is something we have discussed in other threads and some interesting alternative means to move Martian or Lunar soil have appeared. Especially as groundforce is very reliant on the gravity of the planet and as the lower the weight the less effective a standard weight digger will operate.
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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Nice article on the practicalities of digging and processing granular material on Mars. :up:
I remember seeing the lunar rovers scooting around in 0.16g, with 2 heavily-suited astronauts on board, and they didn't seem to have much trouble getting traction.
I don't really understand why it should be harder to drive around on Mars at 0.38g (?). ???
Did the Apollo astronauts have problems driving up slopes on the Moon? I don't recall them having any such difficulties.
The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down. - Rita Rudner
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More than once they would drive up a hill in the LRV, park up, and try to get out only to find they're on quite a steep slope and were worried the rover might tip over
Doug
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I know that they had a large problem with the fender skirting on the rear tires being to small. I remember seeing duck taped cardboard added to them.
As for tipping over? I think the fear was of the near weighlessness effect of equal and opposite reactions to there movement in and out of the vehicle. In that on a slope it would be easier for the rover to move from there exit from it as they pushed themselves from it.
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But there wasn't any problem getting the lunar rover to go up hills - meaning the traction was good?
If so, why should vehicles on Mars have trouble, where the gravity is more than twice as strong? ???
The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down. - Rita Rudner
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I know that they had a large problem with the fender skirting on the rear tires being to small. I remember seeing duck taped cardboard added to them.
That was on one occasion where they accidentally ripped a fender off and the dirt flew EVERYWHERE. They clipped the back of a mission plan onto the rover and bingo - worked a treat
The LRV is one of the most under-celebrated spacecraft ( for that's what it was ) imho
Doug
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*Granular physics is really cool, and I'm surprised there's still much unknown about the solid vs fluid-like situation.
I don't recall -- did any of the Apollo missions involve digging 20 inches or more into the lunar soil? I saw a photo of Fred Haise (Apollo 13) once, training with a drilling device. Of course he didn't get to walk on the moon...but anyway, am wondering if there were any attempts to dig a trench (even a small one) on the moon. ::shrug::
--Cindy
P.S.: Also, I'm almost afraid to ask because I'm not very good at this sort of thing: Can't anything they learn about granular physics and psi (related to equipment weight and soil compression) here on Earth "already" be known on Mars by some simple calculations based on ratios or percentages or whatever, i.e. Mars' gravity is 0.38 of Earth's--? (I have a hunch I already know the answer: NO. But I'll ask anyway.)
We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...
--John Sladek (The New Apocrypha)
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Even though this article is about the subject we are discussing it really aught to be under rover design.
The Sands Of Mars
It does get into some of the answers but I think leaves somethings still to question.
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Just as a matter of reference, the largest hill climb on the Moon was during the Apollo 16 mission. The crew ascended partway up Stone Mountain. They climbed 175m/575 ft in elevation up from the base of the mountain. It took approximately 12 minutes to complete the climb. Slopes on the climb ranged from 8 to 20 degrees. The total weight on the Moon of a loaded Rover with 2 crew riding was approximately 200lbs/91kgs. Slippage was rarely a problem unless the soil was especially thick and soft. djellison makes reference to the fact that crewmembers often could not really sense that they were climbing a slope at the time due to the low gravity. This particular situation was no different.
This image shows the view from the parking spot on the side of the mountain. Although they found a relatively flat spot to park on, you can see that the mountain slopes are fairly steep.
http://www.hq.nasa.gov/alsj/a16/as16-11 … -17960.jpg
References to incidences of crewmembers having to hold the Rover in place were at times when neither crewmember was on sitting in it, and at the same time parked on steep slopes in very soft soil – as the loaded rover alone without crew weighed only 85lbs/38kg on the Lunar surface.
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Many thanks, Greg! :up:
That last post of yours answered my questions perfectly!
This reinforces my opinion that mobility on Mars shouldn't be a major problem because of any fundamental traction/gravitational acceleration factors.
In the past, I've tended to become impatient with doom-and-gloom merchants, who seem intent on placing as many hypothetical obstacles in the way of human Mars exploration as they possibly can. When you look at the way problems were considered and addressed so quickly and in such a matter-of-fact way, back in the Mercury/Gemini/Apollo days, I get frustrated with today's humming-and-hahing and grave tut-tutting over the dangers of Mars expeditions.
By all means, let's examine the potential difficulties and deal with them but does anyone else get the same feeling I do, that we've become ridiculously and unnecessarily fretful about every detail of Martian exploration involving people?
Sorry, I guess this doesn't strictly belong in the 'Unmanned probes' section. :;):
The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down. - Rita Rudner
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Even if manned missions to Mars do prove to be amazingly dangerous (which I doubt), as long as people are willing to go, what's the problem? If the politicians (administrators, whoever) really think it's important, they can only let single people go up, or have the entire family sign waivers with giant letters that every news camera can pick up that say 'WE KNOW JIM MAY DIE' blah blah blah etc etc etc.
It's not like astronauts are forced into space, or that they don't realize it's more than a little dangerous.. Sweet Jesus above, if the fact that astronauts' missions are less safe than staying on the ground and watching 'Desperate Housewives' really becomes such an issue that space missions are utterly cancelled, we're doomed.
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While a much older thread 2007 Mars Scout does exist this is the newer of them for this post.
Next On Mars
2007 will feature Phoenix - the first of the relatively low-cost "Mars Scouts" selected by NASA from competitive proposals by different scientific teams - which is actually the cancelled stationary Mars Surveyor lander originally planned for 2001, re-instrumented to land on the near-surface layer of ice-saturated ground discoverd by the Mars Odyssey orbiter in Mars' north polar regions to study the ice itself and its potential for preserving biochemicals.
The article mentions sort of a before and after probes being the Mars Reconnaissance Orbiter - which will use extremely sharp cameras and spectrometers and a very high communications rate to map virtually the entire planet at very high resolution.
The others after are the Mars Telecommunications Orbiter is the first Mars comsat, which will orbit the planet at high altitude to tremendously increase the rate at which landed vehicles can return science data to Earth.
This in turn is to be followed by the Mars Science Laboratory (MSL) - a rover weighing 600 kg, which is likely to be powered by plutonium-fueled RTG generators rather than less reliable solar arrays - will drive as much as 50 kilometers across the Martian surface over 22 months, after making a precision landing within less than 10 km of a scientifically interesting target point selected by the earlier orbiters.
There is some uncerntainty as to where this will go as previously schedueled.
This article also talks of mission beyound these but we can only wait and see what will happen
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