Posted on 01/09/2004 5:45:17 PM PST by LibWhacker
Less than a week after landing on Mars, the U.S. Spirit spacecraft has found possible evidence that water once flowed on the now-barren planet, the goal of the mission. The scientists are cautious about their interpretation.
Although the Spirit robotic rover has not yet begun its trek over Martian terrain, one of its scientific instruments has remotely detected small amounts of a mineral in nearby soil that hint of ancient water.
The instrument that did this is an infrared camera designed to sense the composition of material from afar by measuring heat emissions.
Mars mission scientist Phil Christensen says the presence of the mineral, called carbonate, might mean its is a remnant of rocks that formed in water from dissolved carbonate particles.
"So it might be that this carbonate actually does indeed have to do with the water that we came to look for," he said.
But Mr. Christensen warns that the mineral does not necessarily mean the landing site called Gusev Crater was an ancient lake, as is believed. The carbonate could have come from atmospheric dust that interacted with rocks and soil without water present.
The six-wheeled robotic explorer will help them determine the answer by examining rocks and soil closely when it eventually departs the Spirit lander. The nature of the soil in which the carbonate is found will reveal a lot.
Cornell University researcher Steven Squyres says if it is in wind-blown dust, it probably came from elsewhere and says nothing about a watery past for Gusev Crater. But if the soil that contains carbonate is coarse, like water sediments, that is evidence that the crater is an ancient lake bed.
"I think we're going to be chasing this carbonate story [for] weeks, months maybe," he said. "What we can do as we start to head out across the countryside is we can look at different patches of soil and we can measure the carbonate abundance is different kinds of soil."
The rover's expedition to do this has been delayed because airbags that cushioned the landing cannot be fully retracted and continue to block its path down Spirit's front ramp. To get around this obstacle, engineers have decided to rotate the lander one-third of a turn to the right and roll it off a secondary ramp on the lander's side late next week.
Steven Squyres says his team is prepared to command the rover to dig with its mechanical arm in whatever direction it heads.
"We always knew that we could egress in any direction and that the egress direction was going to be picked on the basis of safety," he said. "That's part of why we make sure to get a full 360 degree panoramic view. So we're going to be ready to pick targets, ready to do science no matter which direction the egress turns out to be."
In preparation for dispatching the rover, engineers have begun to raise it from its compressed travel position, as if it were a newborn stretching and kicking. The process of expanding the vehicle's legs and wheels to their fully extended position is taking two days.
The rover can travel at the break-neck speed of about 20 yards per day, so mud flaps aren't necessary.
Well, after all these years that explains how Dave was able to blow the emergency door on his pod and fly through space into the main ship without a suit or helmet.
I always wondered about that.
You don't know? How can anyone not know this?
No, wouldn't do that.
Granted: the water triple-point experiment gave cause for alarm. But it seems that the skin we were thoughtfully provided with breaks up that phenomenon so we don't boil off instantly.
Anything proceeding the "water triple-point experiment" comment made my eyes glaze over.
Perhaps if you have the time you can extrapolate?
All that I know is that if somebody was ejected into space, their lungs would proceed to protrude out of their mouth, among other things.
Perhaps that was due to my boyhood Sci-fi reading. It was entitled "The Cold Equation", and the story was about a girl who stowed away on a spaceship which only had enough fuel to accomodate the pilot and supplies required to get medication to a stranded colony on some planet.
She had snuck aboard to see her brother, she was discovered, and the pilot was trying everything he could to keep her aboard, but ultimately had to eject her because she was not part of the "equation" to get the ship from point A to point B.
You would start to dry out, to mummify. This would not be fast. It is not an instantaneous process. You would have up to 240 seconds of consciousness, maybe enough to get from your disabled ship to the rescue ship before you need assistance. You are correct that most people simply don't know about this just as they don't much of anything about outer space. Further inquiry might reveal that that don't know much about anything.
SATURDAY, JANUARY 10, 2004, 1830 GMT (1:30 p.m. EST)
Today was a very successful day for the Spirit rover, mission controllers report, and the mobile robotic geologist could drive off its lander earlier than once envisioned.
The lift mechanism used previously to raise up the rover was retracted back into the lander overnight. Also, Spirit's rear wheels were deployed. The rover is now standing on its six wheels, almost ready to drive on the Martian surface.
On the upcoming workday that begins tonight (Earth time), the middle wheels will be released from the lander and the moveable arm holding science instruments will be unlocked from its launch position and put into the "stowed" position for exiting the lander.
On the Sunday night workday, the final cable line running from the lander to Spirit will be severed -- at which point the base and rover will be separated. The lander becomes a dead platform.
With a puffed up airbag still hampering the forward driveway, engineers have done a test with a model on Earth to determine what would happen if Spirit took that path. The demonstration revealed that there was a chance the left-rear solar panel could brush the bag during the driveoff.
As a result, Spirit will make a 120-degree turn on the lander -- probably on Monday night -- to reach a different exit path. The rover is currently facing south and will turn to head toward the northwest.
The big moment of rolling onto the surface is expected Tuesday night/Wednesday morning.
Yesterday, officials were estimating the lander egress would occur late next week. But it now appears Tuesday night is achievable.
Although, the unforgettable image of our lunar rovers hotrodding across the lunar landscape comes to mind. If only Spirit were powerful enough, and I was at the joystick, I couldn't resist putting the pedal to the medal (so to speak).
The difference in pressure between sea level and a complete vacuum is about the same as the difference between the surface and the bottom of a large swimming pool. You might notice in "2001" that Dave closes his eyes tightly before popping the pod door. Your eyes would dry out quickly in a vacuum. Best to limit exposure to a few seconds. I'm guessing from memory that Dave is exposed to a vacuum for about 15 seconds.
I don't know what relevance this has, maybe some, but I went fishing with some friends once 30 miles outside the Golden Gate. We were pulling rock cod up from 300 feet. The change in pressure was inverting their stomachs; i.e., their stomachs were protruding way out of their mouths. Pretty gross. But they were still good eating! :-)
Nevermind. I guess I'd prefer to remain ignorant.
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