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Posted: Tue May 27, 2008 5:31 pm
by Arramon
*hands cream to those who get butt-hurt from people's opinions/comments*


*hands manual of 'How to not always be so pessimistic' to those who always are*


Good Job EDL Team! Forget the communication foul-up at the end, it all went well and the touchdown was another hole in one (seeing as how the Phoenix would not have risen from its ashes if it crashed). =)

Beats the bouncing method by the Rovers. These techniques with the landing thrusters will just help improve future landings (by robots or humans) now that the data this time around from the affects of the atmosphere can be analyzed and new sequences perfected. Great for similar landings on other worldly bodies. And good ol' parachute. $299.99 at your local Army Depot. (nah.. i have no idea) =b

Can't wait for some chemical compositions to be sent back. Enough panoramas of the landscape already. A rock here, a boulder there. A little midget caveman carrying a baby, waiting for a martian bus... =/

We want martian microbes I say! Maybe they should aim a probe at those huge holes on the surface that lead to subsurface caverns.... hmmmm... now that would be an awesome hole-in-one. I don't think the landing controls are that good though. They always have to wait some time before they even know the lander made it.

Posted: Tue May 27, 2008 7:35 pm
by iamlucky13
Arramon wrote:Beats the bouncing method by the Rovers. These techniques with the landing thrusters will just help improve future landings (by robots or humans) now that the data this time around from the affects of the atmosphere can be analyzed and new sequences perfected. Great for similar landings on other worldly bodies. And good ol' parachute. $299.99 at your local Army Depot. (nah.. i have no idea) =b

Can't wait for some chemical compositions to be sent back. Enough panoramas of the landscape already. A rock here, a boulder there. A little midget caveman carrying a baby, waiting for a martian bus... =/

We want martian microbes I say! Maybe they should aim a probe at those huge holes on the surface that lead to subsurface caverns.... hmmmm... now that would be an awesome hole-in-one. I don't think the landing controls are that good though. They always have to wait some time before they even know the lander made it.
NASA hasn't said yet if they've pinpointed the exact touchdown location, but I've heard rumors that it was at the extreme edge of the anticipated landing zone, which is 20 km x 60 km. Not enough to hit a cave (plus, not knowing what's in the bottom of a cave, that's asking for a bad landing). The bouncing the rovers do only adds an extra kilometer or two to the error.

Most of it is from uncertainty about the position during re-entry, seaonally changing density of the atmosphere (which orbiters can help correct for), and winds.

MSL will try to be that accuracy, however. Right now they're talking 10-20 km accuracy for it.

Perhaps surprisingly to most people, the parachute is far from ordinary. Aside from being a custom-made to be lightweight, it has to be designed to work in both supersonic and subsonic flight. The basic design was worked out for Viking, but it had to be adapted for the MER's and for Phoenix.

Posted: Tue May 27, 2008 8:51 pm
by Doum
Amazing job. Congratulation! Now let see whats outthere. :)

Posted: Tue May 27, 2008 9:35 pm
by BMAONE23
Likely, the best way to do a "Cave" type explorarion would be to send the lander attached to an orbiter like Cassini-Huygens. Have a rover on the lander portion and have a balloon vehicle as part of the rover.
The orbiter can spot the cave approaching and jettison the Lander at the appropriate time. The lander could then touch down within a practicle distance from the cave and launch the rover to drive there. The rover, after reaching the mouth of the cave, would then inflate and release the small autonomus blimp to glide down and into the cave, relaying images and data back through the rover to the orbiter and back here.
The Blimp could then return to and dock with the rover and then travel to the next cave entrance.

Posted: Tue May 27, 2008 11:43 pm
by apodman
And back on Earth in the IMF van, Barney navigates the blimp through the cave by remote control. Fortunately he uses a subspace transmitter to avoid the inconvenient speed-of-light delay.

Posted: Tue May 27, 2008 11:45 pm
by apodman
I know. Smart blimps need no remote operators.

Posted: Wed May 28, 2008 5:20 am
by BMAONE23
Actually, through the use of mercury switches and gravity, the blimp could detect yaw, pitch, ascent, and descent and make
necessary adjustments. Then through simple radar it could detect proxcimity to walls, floor, ceiling, and
obstructions. Add a night vision (low lux) imaging system and a battery life sensor so it doesn't pass PNR before
returning and we could see what is inside up to a point. We have this technology the question would be, could
we make the science package small and light enough so that the Blimp would be feasible.

Posted: Wed May 28, 2008 2:01 pm
by Animation
In the article I read, it said that the attempts to move the arm using the relay (between the orbiter and the lander) failed and that the relay system was in standby.

I'm wondering did they mean "stuck" in standby?

They said they would try again on Wednesday. I'm wondering if there has been any followup or if anything has gone with the relay or if I'm just being nervous for no reason.

Lewis

Posted: Wed May 28, 2008 6:27 pm
by iamlucky13
For some reason, Odyssey didn't relay the commands it received to Phoenix. Normally radio communications are done through the orbiters instead of direct from the surface, because they have more frequent line-of-sight to earth and are also capable of higher data rates.

It does not appear to be a problem with the lander. Most likely a minor glitch in the relay command. There will probably be an update this afternoon.

I'm still awestruck by this picture:

Image

Posted: Fri May 30, 2008 9:04 am
by Javachip
If we're looking for ice, then why did we decide to land on red dirt again? Why didn't we aim for the bright, white, crusty stuff that we can see from Earth on the Martian poles?

Posted: Fri May 30, 2008 11:58 am
by Dr. Skeptic
Javachip wrote:If we're looking for ice, then why did we decide to land on red dirt again? Why didn't we aim for the bright, white, crusty stuff that we can see from Earth on the Martian poles?
New white ice has a far less chance of having organic molecules trapped inside than the dirty ice they landed on. There should less than a centimeter of "Red Dirt" atop dirty ice, "frozen mud" (or permafrost).

Organic molecules are the goal of the mission not the H2O.

Posted: Fri May 30, 2008 1:37 pm
by neufer
Dr. Skeptic wrote:
Javachip wrote:If we're looking for ice, then why did we decide to land on red dirt again?
Why didn't we aim for the bright, white, crusty stuff that we can see from Earth on the Martian poles?
New white ice has a far less chance of having organic molecules trapped inside than the dirty ice they landed on.
There should less than a centimeter of "Red Dirt" atop dirty ice, "frozen mud" (or permafrost).

Organic molecules are the goal of the mission not the H2O.
  • http://library.thinkquest.org/26442/htm ... plant.html

    <<The extreme conditions make Antarctica a habitat in which only the hardiest can
    survive. Very few species have been recorded on the 2% of the continent that is
    ice-free. They include about 150 lichens, 30 mosses, some fungi and one liverwort.

    Only two native vascular plants, the Antarctic hair grass Deschampsia antarctica and
    a cushion-forming pearlwort, Colobanthus quitensis, survive south of 56°S. They occur
    in small clumps near the shore of the west coast of Antarctic Peninsula. This is in
    marked contrast to the Arctic regions where nearly 100 flowering plants are found
    at 84°N. Both plants can tolerate very cold and dry conditions. They continue to
    function at freezing point, when the rate at which they convert sunlight into
    chemical energy drops to about 30 to 40 per cent of that reached
    during the most favourable conditions.

    Lichens

    Of all the plants, lichens are best adapted to survive in the harsh polar climate.
    Some lichens have even been found only about 400 km from the South Pole. Lichens
    have proliferated in Antarctica mainly because there is little competition from
    mosses or flowering plants and because of their high tolerance of drought and cold.
    The peculiarity of lichens is that they are not one homogeneous organism but a
    symbiosis of two different partners, a fungus and an alga. The fungus part supplies
    the plant with water and nutritious salt, meanwhile the alga part organic substance,
    like carbohydrate produce. With this ideal "job-sharing", lichens can survive the
    hardest conditions. Far from the border of highly developed plants, lichens are the
    pioneers of the vegetation. Lichens aren’t only frugal and robust, they jug out
    because of their very low sensibility against frost. Some lichens, in an experiment,
    survived a bath in liquid nitrogen at minus 195 degrees. On icy rock, lichens have
    the same strategy as plants have developed in the sand of the Sahara: they form an
    "oasis". Like in the desert they miss water. They have only a chance to survive, if
    they settle in an area with a convenient, damp microclimate. Since what stops lichens
    to spread over the whole of Antarctica is not so much the big cold as the lack of
    water. For this reason they don’t settle in a place with the most sunshine, but in
    recesses and cracks between rocks. They like scanty soils, created by weathered
    rocks. They often quicken this process with secretion of acid.

    Snowflake are captured in the cracked rock and smelt on the dark lichens, they can
    absorb the vitally liquid. Especially unfavourable conditions are in the "dry valley"
    of East Antarctica, where big coldness and low snowfall meet. But even there
    scientists have found a dark cover on the north side of some rocks, which prove to
    be lichens. Under the microscope it was shown that the lichens penetrate the upper
    coat of the rock. With the dark colour the lichens absorb more light. This strategy
    enables the lichens to scrape a humble living in those quite high southern latitude.
    An often seen lichen is Usnea sphacelata, which looks like a small forest of bonsai.
    They even grow on a height of some centimetres. They can only grow on about 120 day
    per year, so they only grow between 0.01 and 1 millimetre per year. But they live
    very long: an age of 200 years is not unusual, the record is about 4500 years.

    Mosses

    Only a small number of moss species are found in Antarctica. Extensive fields occur
    in a few places on this continent and these are rarely more than 100 mm deep, even in
    the most favourable areas where there is shelter and plenty of water. Short moss turf
    and cushion moss is found most frequently in sandy and gravelly soils. No extensive
    peat formations are to be found. Mosses, like lichens, gather in colonies which make
    them possible to collect and retain more water. They also lose less by evaporation
    and show a marked ability to use water rapidly whenever it becomes available. Mosses
    have also become well adapted to the almost continuous light during the long days
    of a polar summer. One Antarctic moss, Bryum argenteum, produces more energy by
    photosynthesis in low light at 5°C than it does at 15°C, or higher. Photosynthesis
    can start within a few hours of thawing after a prolonged period of freezing,
    and almost immediately following short periods.

    Algae

    More than 300 species of non-marine algae have been found in Antarctica. These very
    simple plants take many diverse forms and a few have become adapted to living in
    difficult polar environments. Blue-green and other algae are found growing in damp
    sand and gravel around lakes and tarns, along meltwater streams or in low-lying
    areas, where snowdrifts or seepage may collect. Some such as Prasiola crispa can
    tolerate high levels of nutrients and are found near bird colonies. Others – the
    snow algae - may form extensive and spectacular red, yellow or green patches in
    areas of permanent snow. Recent studies have shown that some blue-green algae
    live inside rocks in dry valleys. Commonly they are found under stones,
    particularly light-coloured quartz stones, where the microclimate is more
    favourable than in the surrounding sand or soil. Together with lichens,
    they are the only living things in a barren landscape.

    Fungi

    Fungi have been studied little. Several mushrooms have been found on the west coast
    of the Antarctic Peninsula, and on the South Shetland Islands. A few of the fungi
    found in Antarctica are unique to the continent. The majority, however, are also
    found in most temperate areas>>

Posted: Fri May 30, 2008 3:32 pm
by Javachip
If we're merely looking for simple organic molecules on Mars, then I could have saved NASA $400 million -- there are some, just as there are simple hydrocarbons in Jupiter, Saturn, Titan, Uranus, Neptune, and in the ejectae from red giants and supernovae.

I do not think we will find any unequivocal evidence of past or present life, or even the most primitive self-replicating organic molecules. Earth had conditions never present on Mars -- warm liquid water with enough ambient energy to create chemical bonds, at the same time with effective shielding from ionizing cosmic radiation to prevent those complex bonds from being destroyed immediately.

And I agree with a previous poster, that blasting superheated hydrazine combustion products onto the sampling area is not a good idea when looking for trace organic molecules with mass spec instruments that are sensitive to a few parts per billion.

On the other hand, assessing the composition of the white polar frost -- how much of it is CO2 vs. H20 -- would be useful information for future manned exploration of Mars.

Posted: Fri May 30, 2008 5:21 pm
by Arramon
Into those caverns I say!! If Man wants to set a foothold on Mars, what better than to create a colony within an already protected environment? Start some plantgrowth in those holes, get a primitive airsystem going in whatever habitat and create elevators or lifts to get people to and from the interior to the surface.


=/

Maybe in another 50 years. After the Moonbase is established, and refining resources up there is in full swing... AND If those holes ARE open spaces and have stable environments. And other beings don't already occupy them. And there aren't giant worms like on the huge asteroid in Star Wars... =v

Whatever the means, those areas are calling for exploration. What better to explore caves on another planet??? =)

Set up a remote sensing laboratory that can relay data and images to the orbitters, scan the interiors, look for real lifeforms that could have survived below ground. On Earth, life is everywhere, even in the most remote and inhospital environments that could kill a human instantly. Doesn't take much imagination to ponder if life works the same elsewhere. A planet's crust should be pretty good shielding against the Solar barrage if the planet is still active within.

*volunteers to be first human in those caves*

Posted: Fri May 30, 2008 6:08 pm
by Dr. Skeptic
Javachip wrote:If we're merely looking for simple organic molecules on Mars, then I could have saved NASA $400 million -- there are some, just as there are simple hydrocarbons in Jupiter, Saturn, Titan, Uranus, Neptune, and in the ejectae from red giants and supernovae.

I do not think we will find any unequivocal evidence of past or present life, or even the most primitive self-replicating organic molecules. Earth had conditions never present on Mars -- warm liquid water with enough ambient energy to create chemical bonds, at the same time with effective shielding from ionizing cosmic radiation to prevent those complex bonds from being destroyed immediately.

And I agree with a previous poster, that blasting superheated hydrazine combustion products onto the sampling area is not a good idea when looking for trace organic molecules with mass spec instruments that are sensitive to a few parts per billion.

On the other hand, assessing the composition of the white polar frost -- how much of it is CO2 vs. H20 -- would be useful information for future manned exploration of Mars.
It is not just any organic molecules; it’s the types of organic molecules (if any) and reverse engineering how they came to be.

The arm (in theory) can dig a trench up to a meter in depth well away from any residual hydrazine contamination - hydrazine does not contain any carbon, hydrocarbons or organic compounds that would produce inaccurate results.

NASA has included an Atomic Force Microscope in the Phoenix toolbox that has the resolution of fractions of a nanometer to aid in the identification of both organic and inorganic structures that may be present in the soil (such as bacterial fossils?).

Posted: Sat May 31, 2008 10:31 am
by JohnD
iamlucky13 wrote:And don't forget, NASA, ESA, Japan, and Russia have all messed up Mars missions easier than this. If Phoenix continues to be successful, it will be the first time the international space community has broken the 50% mark for Mars mission success:
Just to even up the failure score - and the UK! (BeagleII)
Even if it did get a ride there as a stowaway on the otherwise successful, but non-landing ESA Mars Express.

John

Posted: Sat May 31, 2008 5:43 pm
by henk21cm
Dr. Skeptic wrote: NASA has included an Atomic Force Microscope in the Phoenix toolbox that has the resolution of fractions of a nanometer to aid in the identification of both organic and inorganic structures that may be present in the soil (such as bacterial fossils?).
I have some doubts about the use of an AFM on Mars. The sensing tip of such instrument is the most delicate part. How did it survive the multiple g's during launch? An AFM is a suitable instrument for studying flat surfaces, like (micro) crystals, maybe an isolated clay plate. A curved surface like a silt particle or a grain of sand is less suitable. Focussing range is only a few micro meters. Particle roughness and edgeness is a major danger for damaging the tip. Not in the least that the AFM has to be integrated in a solid and steady environment. Vibrations produces fuzzy or foggy results. If Phoenix is exposed to Martian winds, it will vibrate.

The philosophy might have been: "Ok, if you don't shoot, you will never eat rabit, it is worth trying". These topics will have been dealt with in the final design review (hopefully).

Posted: Mon Jun 02, 2008 5:26 pm
by iamlucky13
Interesting points about the AFM. Presumably they've thought of these things.

I believe the AFM is mounted on the rover body, and samples are held in front of it on a collector plate built into the robotic arm, but certainly the robotic arm would be more prone to vibration than the rest of the lander.

Hmmm...crazy NASA.