Yes that is the "invisible" elephant swinging in the breeze of course .. makes it a win win?bdw000 wrote:I am not claiming personal knowledge here, but dishonesty on the part of any "space agency" is ALWAYS a "possibility."kiwi wrote:... no other possibillity is there?
'Welease Wosetta!'
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Re: 'Welease Wosetta!'
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Re: 'Welease Wosetta!'
Unless a sheet of paper is enough leverage weight to have a drill bit pierce a surface--and then break--including any other instrument lowered onto the surface--then no: there is no other possibility.kiwi wrote:Yes ... so MUST be "wedged" in tight ... no other possibillity is there?WIthout the 1 gram of Philae being anchored down to
How can 1 gram of pressure break anything?
For this case, in my opinion, any deployed instrument making surface contact will have acted as a catapult, raising Philae off the surface no matter what they did. I feel this is fair game to assume. The condition is so extreme for the lander, 1/100,000th g, that there is no other way to see this.
But how do instruments designed for space travel and geologic experiments break under the weight of a business card or sheet of paper? How could have any of the deployed things penetrated anything if Philae was never secured to the surface?
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Philae spot-welded itself to the surface with a zap? What kind of thruster was used to hold the probe down while the anchors tried to work? A chemical thruster, or an electric engine?viscount aero wrote:kiwi wrote:Yes ... so MUST be "wedged" in tight ... no other possibillity is there?WIthout the 1 gram of Philae being anchored down to
I've also heard of something called contact welding—when metal outgasses in a vacuum so that simple contact is enough to weld it to another piece of metal. Somehow I doubt that could have happened. Most likely Philae's bounce across the landscape wedged an extremity into a rough edge. (The sort of chance occurrence that never would have happened if the designers were trying to do it.)
Maybe Philae landed on an outcrop of lodestone?
Or maybe 67P has a much higher gravity, and electric repulsion was mucking up the figures.
Laser drills? Let me guess, Philae doesn't have any lasers, let alone the power for anything above a laser pointer. Although I imagine Rosetta might have a laser spectrometer to detect all the ice.How could have any of the deployed things penetrated anything if Philae was never secured to the surface?
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Of course you're kidding mostly The hold-down thruster didn't work on Philae. Nothing did in that regard.Metryq wrote:Philae spot-welded itself to the surface with a zap? What kind of thruster was used to hold the probe down while the anchors tried to work? A chemical thruster, or an electric engine?viscount aero wrote:kiwi wrote:Yes ... so MUST be "wedged" in tight ... no other possibillity is there?WIthout the 1 gram of Philae being anchored down to
I've also heard of something called contact welding—when metal outgasses in a vacuum so that simple contact is enough to weld it to another piece of metal. Somehow I doubt that could have happened. Most likely Philae's bounce across the landscape wedged an extremity into a rough edge. (The sort of chance occurrence that never would have happened if the designers were trying to do it.)
Maybe Philae landed on an outcrop of lodestone?
Or maybe 67P has a much higher gravity, and electric repulsion was mucking up the figures.
Laser drills? Let me guess, Philae doesn't have any lasers, let alone the power for anything above a laser pointer. Although I imagine Rosetta might have a laser spectrometer to detect all the ice.How could have any of the deployed things penetrated anything if Philae was never secured to the surface?
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Re: 'Welease Wosetta!'
This is one of the most profound and insightful strings of recent comments. How can you tell how hard something is if applying more than 1g of pressure lifts you up off the surface? Apologies if this has already been posted somewhere, but the Rosetta engineer team appeared on Reddit the other day to answer questions to the public:viscount aero wrote:Yes so any reports of a "hard" or "soft" surface with the lander weighing only 1 gram will be nearly meaningless. Without being secured to the surface of the comet then any instruments deployed will act as catapults. The lander then cannot really do anything. That it became stuck in a crevice is actually a good thing except that it's in the dark (provided the "stuck" actually secured it to the surface--a blessing). If only it got stuck in the sunlight it could have probably drilled and hammered and sniffed all year. But the 'what ifs' are useless. It is what it is.Dotini wrote:If I weighed only one gram and hammered on a bowl of Jell-O, I might achieve lift-off from my chair.viscount aero wrote:That is correct, particularly since Philae weighs only 1 gram on the comet. Without any anchoring or downward pressure to secure tools as they are deployed then the tools cannot function. Gravity is needed. In this virtual non-existence of gravity then any surface becomes "hard." So what does "hard" mean?dodeca wrote:Because Philae was not anchored to the comet surface, it is also possible that, if the drill touched a particularly hard surface material, it moved the lander instead of drilling into the surface.
So I too question how effectively MUPUS was able operate without Philae being normal to a surface and being tethered down tight with the ice screws at the 3 feet. We know at least one foot was dangling in the air. Or is it conceivable the structure of the craft was wedged into the rock like a climber's jam nut?
http://www.reddit.com/r/IAmA/comments/2 ... d_science/
Some good stuff, some lame. Near the end of the comments, one scientist says that a brick dropped from a height of 5 feet on 67P would take about three minutes to fall to the surface. Really helps to put this whole 'low gravity environment' in an accessible perspective.
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Granted, hammering the Jell-O might well send you off into space. But remember that while weighing only a gram, you (or a lander) would mass far more than a gram. The surface tension of a gelatin dessert should be enough to launch a piece of paper, but something massing more than a sheet of paper might penetrate the surface (depending on the area of the contact point).Dotini wrote:If I weighed only one gram and hammered on a bowl of Jell-O, I might achieve lift-off from my chair.
This is not to say that Philae's tools should be effective. Just trying to keep the weight/mass thing in perspective.
And now Dotini has initiated the "dirty Jell-O" model for comets.
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Re: 'Welease Wosetta!'
With two scenario's to be considered
1 The thing is wedged in tight
2 She sit's on the surface under her own "weight"
The querys will take on different legitimacy depending under which condition it is being considered .... there is the 3rd optoin that they are not being straight with their data but best ignored as it becomes pointless to proceed from that angle, although it may well be true to some degree.
Here again though its obvious that the further you attempt to investigate under the "accepted" law's of Physics it is not long before total confusion reigns, for me its another indicator that once all the hubris is peeled away there are NO reliable and fully known "fundamentals" supporting it. We are doomed to chase our tails forever until the whole shebang is shaken like a dirty rug and we start again from scratch
1 The thing is wedged in tight
2 She sit's on the surface under her own "weight"
The querys will take on different legitimacy depending under which condition it is being considered .... there is the 3rd optoin that they are not being straight with their data but best ignored as it becomes pointless to proceed from that angle, although it may well be true to some degree.
Here again though its obvious that the further you attempt to investigate under the "accepted" law's of Physics it is not long before total confusion reigns, for me its another indicator that once all the hubris is peeled away there are NO reliable and fully known "fundamentals" supporting it. We are doomed to chase our tails forever until the whole shebang is shaken like a dirty rug and we start again from scratch
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Re: 'Welease Wosetta!'
Even with more mass than a sheet of paper, Philae's 1 g weight is not enough to leverage against the drill bit for a penetration in my opinion. I cannot actually know this unless I were to demonstrate it in a lab, but that is my opinionMetryq wrote:Granted, hammering the Jell-O might well send you off into space. But remember that while weighing only a gram, you (or a lander) would mass far more than a gram. The surface tension of a gelatin dessert should be enough to launch a piece of paper, but something massing more than a sheet of paper might penetrate the surface (depending on the area of the contact point).Dotini wrote:If I weighed only one gram and hammered on a bowl of Jell-O, I might achieve lift-off from my chair.
This is not to say that Philae's tools should be effective. Just trying to keep the weight/mass thing in perspective.
And now Dotini has initiated the "dirty Jell-O" model for comets.
Why I say this is because Philae has no velocity or momentum (or leverage pressure) behind it. For example, all objects in space weigh nothing, from a feather to a ball of lead. But if you were in the path of a 50,000 km/hr projectile in space, weighing nothing, and it hit you, it would destroy your body. Whereas Philae's momentum relative to the comet is 0. And its weight is near 0.
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Re: 'Welease Wosetta!'
Agreed. If Philae massed as little as a sheet of paper, the drill wouldn't stand a chance of even scratching the surface of 67P. Since it does mass more than that, it might have the inertia to scuff the surface, but not enough for the drill to bite in.viscount aero wrote:Even with more mass than a sheet of paper, Philae's 1 g weight is not enough to leverage against the drill bit for a penetration in my opinion.
Not to change the subject, but too bad Philae doesn't have "gecko feet":
http://www.iflscience.com/physics/bizar ... ve-gravity”
(You'll have to copy-and-paste the URL; the quotes in that address are keeping the BBcode from working properly.)
I find it amusing that the rotation of 1950 DA isn't enough to suggest to astronomers that the body must be a solid mass. Instead, they stick (pardon the pun) with the notion that it's a loose pile of rubble—because the nebular hypothesis says it must be—and take off on wild goose chases for exotic reasons why it stays together. More funding is needed to study the problem.
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I don't quite follow your syntax but I understand what you're saying. Suffice it to say, there isn't enough gravity (weight) on either the comet or the lander for them to practically interact. Mass doesn't change but the gravity (weight) does. In space there is no weight until objects locally interact within the critical distances of each's gravity envelope. In this case with 67P and Philae, it is almost as if there were zero gravity between the two objects. In this condition there is virtually no leveraging ability for work to occur.Metryq wrote:Agreed. If Philae massed as little as a sheet of paper, the drill wouldn't stand a chance of even scratching the surface of 67P. Since it does mass more than that, it might have the inertia to scuff the surface, but not enough for the drill to bite in.viscount aero wrote:Even with more mass than a sheet of paper, Philae's 1 g weight is not enough to leverage against the drill bit for a penetration in my opinion.
This is a large reason why I don't understand how a drill could "break" when it was subjected to virtually zero friction or work. And why did some of the major external systems fail? It seems too many of them failed to be written off as mere coincidence.
Great post; I'm glad you changed the subject--sort of. This is an example of a theory being categorically falsified, ergo, that "asteroids are known to be rubble piles loosely held together by gravity." Who ever thought of that theory and why did it become so popular? All asteroids are absolutely rubble piles? I never believed it and do not believe it. And this fast-rotating one falsifies it.Metryq wrote:Not to change the subject, but too bad Philae doesn't have "gecko feet":
http://www.iflscience.com/physics/bizar ... ve-gravity”
(You'll have to copy-and-paste the URL; the quotes in that address are keeping the BBcode from working properly.)
I find it amusing that the rotation of 1950 DA isn't enough to suggest to astronomers that the body must be a solid mass. Instead, they stick (pardon the pun) with the notion that it's a loose pile of rubble—because the nebular hypothesis says it must be—and take off on wild goose chases for exotic reasons why it stays together. More funding is needed to study the problem.
Moreover, it is laughable that they are implying "Van der Waals" forces" as holding the asteroid together. Read about it and see how preposterous it is when applied to asteroids
http://en.wikipedia.org/wiki/Van_der_Waals_force
Mind you it is the only one of its kind, evidently, that they have thus far detected. But space is giant and rocks are very small
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Re: 'Welease Wosetta!'
Forgive me, but every time I hear "small rocks" I can't help but think of that scene in MONTY PYTHON AND THE HOLY GRAIL about the witch.viscount aero wrote:But space is giant and rocks are very small
BEDEMIR: What also floats in water?
VILLAGER #1: Bread!
VILLAGER #2: Apples!
VILLAGER #3: Very small rocks!
Feels like professional astronomy these days. (Okay, so now we've worked our way from LIFE OF BRIAN to HOLY GRAIL. I guess that makes Philae the five ounce bird.)
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Good oneMetryq wrote:Forgive me, but every time I hear "small rocks" I can't help but think of that scene in MONTY PYTHON AND THE HOLY GRAIL about the witch.viscount aero wrote:But space is giant and rocks are very small
BEDEMIR: What also floats in water?
VILLAGER #1: Bread!
VILLAGER #2: Apples!
VILLAGER #3: Very small rocks!
Feels like professional astronomy these days. (Okay, so now we've worked our way from LIFE OF BRIAN to HOLY GRAIL. I guess that makes Philae the five ounce bird.)
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Re: 'Welease Wosetta!'
The mission has become a bit hilarious.viscount aero wrote:Good oneMetryq wrote:Forgive me, but every time I hear "small rocks" I can't help but think of that scene in MONTY PYTHON AND THE HOLY GRAIL about the witch.viscount aero wrote:But space is giant and rocks are very small
BEDEMIR: What also floats in water?
VILLAGER #1: Bread!
VILLAGER #2: Apples!
VILLAGER #3: Very small rocks!
Feels like professional astronomy these days. (Okay, so now we've worked our way from LIFE OF BRIAN to HOLY GRAIL. I guess that makes Philae the five ounce bird.)
Since the beginning of Rosetta's arrival I have been picturing in my head the scenes from The Princess Bride. Viscelli saying inconceivable. There is some project manager getting results from his subordinates and after every report he says, "In-Con-Ceivable!"
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Re: 'Welease Wosetta!'
Yes.Frantic wrote:The mission has become a bit hilarious.viscount aero wrote:Good oneMetryq wrote:Forgive me, but every time I hear "small rocks" I can't help but think of that scene in MONTY PYTHON AND THE HOLY GRAIL about the witch.viscount aero wrote:But space is giant and rocks are very small
BEDEMIR: What also floats in water?
VILLAGER #1: Bread!
VILLAGER #2: Apples!
VILLAGER #3: Very small rocks!
Feels like professional astronomy these days. (Okay, so now we've worked our way from LIFE OF BRIAN to HOLY GRAIL. I guess that makes Philae the five ounce bird.)
Since the beginning of Rosetta's arrival I have been picturing in my head the scenes from The Princess Bride. Viscelli saying inconceivable. There is some project manager getting results from his subordinates and after every report he says, "In-Con-Ceivable!"
It underscores no matter what or how many probes they send out they already know what they're going to conclude no matter what data is gathered. It is as if going to the celestial body doesn't matter.
Rosetta is a prime example, just as I predicted: no matter what they see or gather, the sublimating icy dirtball theory will be confirmed more than ever. That is exactly what happened.
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