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Air Bag Blocks Spirit's Path
cosog writes "bad news everyone: 'Two sections of the air bags used to cushion Spirit during the landing phase are obstructing the vehicle's path.'. Fortunately scientists have a solution for it: 'We'll lift up the left petal of the lander, retract the airbag, then let the petal back down[...]'. This means that: 'The earliest the six-wheeled Spirit rover will get rolling is Jan. 14, about three days later than originally planned, NASA said'."
Info here fourth paragraph
Your comment history doesn't seem too trollish, so here goes. I'll be getting modded offtopic with the rest of the thread, but what's new.
This "thrown free" bullshit cracks me up every time.
A previous poster has already addressed the reality of landing. Now, before we even get there: what about the construction of your car makes you think that you'll be "thrown free" if broadsided by a train? Let's look at a passenger-side impact, since you'd be dead in either case if hit from the driver's side. In fact, even if hit from the passenger side, your chances are slim.
At impact, the train will continue towards you, through your car. Your car will gain velocity in the direction of the train. If you're "thrown" anywhere, you'll be thrown towards the front of the train as it plows through and accelerates your car, and that's only because you remained at rest since you weren't attached to the car.
Your new relative velocity to the car/train system means that your unrestrained torso will be thrown over the center console (assuming you're not in a truck), allowing your head to meet the passenger side of your car as it's crushed inwards by the impact. Game over.
With the seatbelt on, you remain (relatively) planted in your seat. You might injure your neck, as your head doesn't have lateral restraints, but the entire right side of the car is available to absorb the energy of the collision without your body being present. If you're in a car with side curtain airbags, so much the better. You will then slowly come to a halt as the train stops.
The "being plowed along" part is not really the variable affected by seat belt use. You will be plowed along whether you're wearing a seat belt or not; there is no way the impact of the train would "throw you free" in a side collision. If your car disintegrates and is mowed over by the train during the ensuing slowdown, you'll die either way. Seat belt use will, however, affect what happens to your body during impact.
I would challenge any advocate of the "thrown free" argument to explain a single situation in which a body could be "thrown free" from a car in a way that would result in less injury than remaining restrained in the vehicle, even ignoring the hazard from landings.
Rear-end collision? You gain relative velocity towards your seat, no problem.
Side collision? Detailed as above - you gain relative velocity towards whatever hits you, not some magical boost away from it and out the (open? do you ride everywhere with your windows open for safety?) window to "safety."
Front collision? Hey, you might indeed be "thrown free", but there's going to be unpleasant encounters first: steering wheel vs. torso, and head vs. windshield. Airbags and or seatbelts prevent or lesson the impact of both of these encounters. People smarter than you designed and throughly tested these systems.
Those rare collisions in which the car flips are the only kind that might result in you being thrown free, and even in these cases the odds of you being better off outside the vehicle are slim (as in the case below of the half-in/half-out person).
If you're riding without your airbag and seatbelt because you know the risks and accept them because your prefer to be comfortable, fine. But don't go around telling people that they're better off. If you're riding w/o a seatbelt or airbag you're much more likely to get in a garden-variety head-on collision and shatter your skull on the windshield than you are to be flipped and safely thrown free.
Not true. the Pathfinder rover had an onboard battery that eventually died. During the day, the solar cells powered the rover. At night, non-rechargable lithium batteries kept it going. When the batteries were dead, that was the end of the mission.
This is America, damnit. Speak Spanish!
CARS DON'T EXPLODE!
If you've ever seen a car on fire (which happens all the time), it is obviously a very dangerous situation, but it ain't no bomb. People get this idea from movies, to the point where they never reflect upon the plausibility of the whole thing.
The only way I can think of for a car to explode is for the fuel tank to be completely demolished during a crash in such a way that none of the fuel ignites. Then, the fuel Whoooshes out into the air and achieves a good fuel/air mixture, and at just the right moment, something ignites the whole deal. The correct fuel/air mixture is the (very) hard thing to come by.
Fact is, the scenario I just presented doesn't happen much. Even those exploding trucks from about 15 years ago pretty much turned into flamethrowers, not bombs. If anyone has any references (e.g. news stories) about a single car exploding, I'll happily eat my words.
Yes, I'm still a junky. Are you still a bitch?
I believe they said, "Mars doesn't have any oxygen in its atmosphere."
Which is why you'd have to bring along extra oxygen.
:)
You bean counter!
I just watched the live JPL NASA webcast and they said that the wheel technique did not work, today they will lower the wheel back down and try to retract the bag by revolving the retraction motor 6 more times. If it does not work, they still have plenty of other possible routes; they are just trying to make sure nothing is compromised so early in the mission.