Mixing
Acceleration due to uncontrolled rotation of Gemini 8
Clash Royale CLAN TAG#URR8PPP
up vote
1
down vote
favorite
Having just watched the movie "First Man," I'm interested in analyzing the Gemini 8 malfunction in physics terms and possibly turning it into a homework problem or an example for my physics classes. I would like to get the facts right and get the numerical data as accurate as possible. There was some kind of board of inquiry afterward, and I would imagine that its findings are available somewhere online, presumably with engineering data and reconstructions, but WP doesn't link to any such document. Is there such a thing that is accessible to the public?
WP says, "By now the tumble rate had reached one revolution per second, blurring the astronauts' vision and threatening loss of consciousness or vertigo." In the film, there is a dial that goes up to 360, and the needle appears to be pinned at the moment of fastest rotation. I assume that this is in units of degrees per second. Is there any more accurate value available for the maximum rate of rotation?
WP describes the motion as a yaw, which I assume means a yaw in a coordinate system oriented according to the way the astronauts were seated in the Gemini capsule. Did it continue to be a pure yaw after decoupling from the Agena, presumably because it was being caused by a yaw thruster on the Gemini capsule?
How far were the astronauts from the yaw axis? From this NASA artwork, my best guess is that each astronaut's heart was something like 40 or 50 cm away from the yaw axis, i.e., where the cup holders would be in a modern car, but it's pretty hard to tell for sure. An engineering drawing would probably allow this to be determined much more accurately.
Using a period of rotation of 1 second and $r=45 textcm$, I get an acceleration of $1.8g$. Is this in the right ballpark for the effects described in the WP quote? I would imagine that a sideways acceleration like this would be somewhat less dire than an upward acceleration, which would prevent blood from getting to the brain.
crewed-spaceflight history accident project-gemini
asked 5 hours ago
Ben Crowell
1,034512
add a comment |Â
up vote
1
down vote
favorite
Having just watched the movie "First Man," I'm interested in analyzing the Gemini 8 malfunction in physics terms and possibly turning it into a homework problem or an example for my physics classes. I would like to get the facts right and get the numerical data as accurate as possible. There was some kind of board of inquiry afterward, and I would imagine that its findings are available somewhere online, presumably with engineering data and reconstructions, but WP doesn't link to any such document. Is there such a thing that is accessible to the public?
WP says, "By now the tumble rate had reached one revolution per second, blurring the astronauts' vision and threatening loss of consciousness or vertigo." In the film, there is a dial that goes up to 360, and the needle appears to be pinned at the moment of fastest rotation. I assume that this is in units of degrees per second. Is there any more accurate value available for the maximum rate of rotation?
WP describes the motion as a yaw, which I assume means a yaw in a coordinate system oriented according to the way the astronauts were seated in the Gemini capsule. Did it continue to be a pure yaw after decoupling from the Agena, presumably because it was being caused by a yaw thruster on the Gemini capsule?
How far were the astronauts from the yaw axis? From this NASA artwork, my best guess is that each astronaut's heart was something like 40 or 50 cm away from the yaw axis, i.e., where the cup holders would be in a modern car, but it's pretty hard to tell for sure. An engineering drawing would probably allow this to be determined much more accurately.
Using a period of rotation of 1 second and $r=45 textcm$, I get an acceleration of $1.8g$. Is this in the right ballpark for the effects described in the WP quote? I would imagine that a sideways acceleration like this would be somewhat less dire than an upward acceleration, which would prevent blood from getting to the brain.
crewed-spaceflight history accident project-gemini
asked 5 hours ago
Ben Crowell
1,034512
add a comment |Â
up vote
1
down vote
favorite
up vote
1
down vote
favorite
Having just watched the movie "First Man," I'm interested in analyzing the Gemini 8 malfunction in physics terms and possibly turning it into a homework problem or an example for my physics classes. I would like to get the facts right and get the numerical data as accurate as possible. There was some kind of board of inquiry afterward, and I would imagine that its findings are available somewhere online, presumably with engineering data and reconstructions, but WP doesn't link to any such document. Is there such a thing that is accessible to the public?
WP says, "By now the tumble rate had reached one revolution per second, blurring the astronauts' vision and threatening loss of consciousness or vertigo." In the film, there is a dial that goes up to 360, and the needle appears to be pinned at the moment of fastest rotation. I assume that this is in units of degrees per second. Is there any more accurate value available for the maximum rate of rotation?
WP describes the motion as a yaw, which I assume means a yaw in a coordinate system oriented according to the way the astronauts were seated in the Gemini capsule. Did it continue to be a pure yaw after decoupling from the Agena, presumably because it was being caused by a yaw thruster on the Gemini capsule?
How far were the astronauts from the yaw axis? From this NASA artwork, my best guess is that each astronaut's heart was something like 40 or 50 cm away from the yaw axis, i.e., where the cup holders would be in a modern car, but it's pretty hard to tell for sure. An engineering drawing would probably allow this to be determined much more accurately.
Using a period of rotation of 1 second and $r=45 textcm$, I get an acceleration of $1.8g$. Is this in the right ballpark for the effects described in the WP quote? I would imagine that a sideways acceleration like this would be somewhat less dire than an upward acceleration, which would prevent blood from getting to the brain.
crewed-spaceflight history accident project-gemini
asked 5 hours ago
Ben Crowell
1,034512
Having just watched the movie "First Man," I'm interested in analyzing the Gemini 8 malfunction in physics terms and possibly turning it into a homework problem or an example for my physics classes. I would like to get the facts right and get the numerical data as accurate as possible. There was some kind of board of inquiry afterward, and I would imagine that its findings are available somewhere online, presumably with engineering data and reconstructions, but WP doesn't link to any such document. Is there such a thing that is accessible to the public?
WP says, "By now the tumble rate had reached one revolution per second, blurring the astronauts' vision and threatening loss of consciousness or vertigo." In the film, there is a dial that goes up to 360, and the needle appears to be pinned at the moment of fastest rotation. I assume that this is in units of degrees per second. Is there any more accurate value available for the maximum rate of rotation?
WP describes the motion as a yaw, which I assume means a yaw in a coordinate system oriented according to the way the astronauts were seated in the Gemini capsule. Did it continue to be a pure yaw after decoupling from the Agena, presumably because it was being caused by a yaw thruster on the Gemini capsule?
How far were the astronauts from the yaw axis? From this NASA artwork, my best guess is that each astronaut's heart was something like 40 or 50 cm away from the yaw axis, i.e., where the cup holders would be in a modern car, but it's pretty hard to tell for sure. An engineering drawing would probably allow this to be determined much more accurately.
Using a period of rotation of 1 second and $r=45 textcm$, I get an acceleration of $1.8g$. Is this in the right ballpark for the effects described in the WP quote? I would imagine that a sideways acceleration like this would be somewhat less dire than an upward acceleration, which would prevent blood from getting to the brain.
crewed-spaceflight history accident project-gemini
crewed-spaceflight history accident project-gemini
asked 5 hours ago
Ben Crowell
1,034512
asked 5 hours ago
Ben Crowell
1,034512
edited 5 hours ago
asked 5 hours ago
Ben Crowell
1,034512
asked 5 hours ago
Ben Crowell
1,034512
asked 5 hours ago
Ben Crowell
1,034512
1,034512
add a comment |Â
add a comment |Â
1 Answer
1
active
oldest
votes
up vote
4
down vote
accepted
A more authoritative source than Wikipedia would be NASA's Gemini VII Mission Report. Starting on page 5-25, the anomaly is described, with the main effect being an uncontrolled roll peaking at somewhat less than one revolution per second rather than Wikipedia's yaw:
Separation from the GATV [Agena] occurred at 7:15:12.3 GET with thrusÂÂters ll and 12 firing for 6.6 seconds. Rates at this time were +3, -5, and -2 deg/sec in pitch, roll, and yaw, respectively. After separation, moderate hand-controller activity was present, although the direct mode was not sufficient to contain the roll rate. At 7:15:44.7 GET, the ACME bias power was inadvertantly removed, disÂÂabling the control system, and the roll rate increased to 296 deg/sec over the next three minutes, due to the uncontrolled firing of thruster 8, although short periods of intermittent or degraded thruster 8 performance appeared to exist.
The roll axis is of course the longitudinal axis of the spacecraft; a seated astronaut facing forward in the Gemini couch is looking parallel to the roll axis.
The Gemini cockpit was quite cramped; picture the front seats of a small roadster, not an SUV. The couches are canted slightly apart from each other:
...so the roll axis passes not far from each astronaut's inboard hip -- your 45cm axis-to-heart estimate seems plausible, though with a high roll rate, excessive blood flow to the head would seem the more pressing problem, and the radius of concern might be more like 1 meter (the spacecraft being 3m in diameter)... although, mumble, acceleration gradient, calculus, grumble grumble
The crew debriefing document is also available, with more subjective impressions of the incident; Armstrong and Scott mention yaw but confirm the primary mode was roll:
Armstrong: Shortly after backing off, we noticed that we were essentially losing control of the spacecraft in roll and yaw and we suspected that we were over the life time of these attitude thrusters. The spacecraft was continuing, however, to accelerate, and we were obÂÂtaining rates in roll at least that approached 200 to
300 degrees per second, or perhaps more.
Scott: Yes, I would agree with that. It looked like even more to me, and it was by far more in roll than in yaw. The roll was the most predominate. [sic]
Armstrong: We realized that physiological limits were being apÂÂproached, and that we were going to have to do someÂÂthing immediately, in order to salvage the situation.
(You’ve got to love that professional detachment!)
answered 4 hours ago
Russell Borogove
72.9k2227311
Very nice write-up!
– Organic Marble
3 hours ago
Excellent answer, thanks! I've edited WP to change all the references to "yaw" into references to "roll." (Maybe someone else could do a more nuanced and careful edit to WP.) This seems like a perfect answer except for the lack of more authoritative/better sourced info on the physiology. I would think that the difference in (fictitious) gravitational potential between heard and brain would be the important number...? It's unfortunate that the diagram doesn't have a scale. Would the circle be 3 m? Is the 3 m an inside diameter? It was a cone, right?
– Ben Crowell
3 hours ago
Yeah, I've got no idea what the intersection of calculus and physiology is there; if you're making it a physics class problem you might just stop at "what's the radial acceleration at Armstrong's heart" (or head) and leave the health implications vague. :)
– Russell Borogove
3 hours ago
Based on this diagram space1.com/Spacecraft_Data/Handbook_Illustrations/Gemini/… , I think the circle on the figure you reproduced probably has a diameter of about 88 inches. The walls appear to be quite thin (wow!), so there is probably not a huge difference between ID and OD. Guessing the location of a human heart from the cutaway view that I linked to, I find an $r$ very close to the 45 cm that I originally estimated.
– Ben Crowell
3 hours ago
Ah, ok, the 3m is the base diameter of the retro/equipment module, not the crew capsule illustrated.
– Russell Borogove
3 hours ago
add a comment |Â
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
4
down vote
accepted
A more authoritative source than Wikipedia would be NASA's Gemini VII Mission Report. Starting on page 5-25, the anomaly is described, with the main effect being an uncontrolled roll peaking at somewhat less than one revolution per second rather than Wikipedia's yaw:
Separation from the GATV [Agena] occurred at 7:15:12.3 GET with thrusÂÂters ll and 12 firing for 6.6 seconds. Rates at this time were +3, -5, and -2 deg/sec in pitch, roll, and yaw, respectively. After separation, moderate hand-controller activity was present, although the direct mode was not sufficient to contain the roll rate. At 7:15:44.7 GET, the ACME bias power was inadvertantly removed, disÂÂabling the control system, and the roll rate increased to 296 deg/sec over the next three minutes, due to the uncontrolled firing of thruster 8, although short periods of intermittent or degraded thruster 8 performance appeared to exist.
The roll axis is of course the longitudinal axis of the spacecraft; a seated astronaut facing forward in the Gemini couch is looking parallel to the roll axis.
The Gemini cockpit was quite cramped; picture the front seats of a small roadster, not an SUV. The couches are canted slightly apart from each other:
...so the roll axis passes not far from each astronaut's inboard hip -- your 45cm axis-to-heart estimate seems plausible, though with a high roll rate, excessive blood flow to the head would seem the more pressing problem, and the radius of concern might be more like 1 meter (the spacecraft being 3m in diameter)... although, mumble, acceleration gradient, calculus, grumble grumble
The crew debriefing document is also available, with more subjective impressions of the incident; Armstrong and Scott mention yaw but confirm the primary mode was roll:
Armstrong: Shortly after backing off, we noticed that we were essentially losing control of the spacecraft in roll and yaw and we suspected that we were over the life time of these attitude thrusters. The spacecraft was continuing, however, to accelerate, and we were obÂÂtaining rates in roll at least that approached 200 to
300 degrees per second, or perhaps more.
Scott: Yes, I would agree with that. It looked like even more to me, and it was by far more in roll than in yaw. The roll was the most predominate. [sic]
Armstrong: We realized that physiological limits were being apÂÂproached, and that we were going to have to do someÂÂthing immediately, in order to salvage the situation.
(You’ve got to love that professional detachment!)
answered 4 hours ago
Russell Borogove
72.9k2227311
Very nice write-up!
– Organic Marble
3 hours ago
Excellent answer, thanks! I've edited WP to change all the references to "yaw" into references to "roll." (Maybe someone else could do a more nuanced and careful edit to WP.) This seems like a perfect answer except for the lack of more authoritative/better sourced info on the physiology. I would think that the difference in (fictitious) gravitational potential between heard and brain would be the important number...? It's unfortunate that the diagram doesn't have a scale. Would the circle be 3 m? Is the 3 m an inside diameter? It was a cone, right?
– Ben Crowell
3 hours ago
Yeah, I've got no idea what the intersection of calculus and physiology is there; if you're making it a physics class problem you might just stop at "what's the radial acceleration at Armstrong's heart" (or head) and leave the health implications vague. :)
– Russell Borogove
3 hours ago
Based on this diagram space1.com/Spacecraft_Data/Handbook_Illustrations/Gemini/… , I think the circle on the figure you reproduced probably has a diameter of about 88 inches. The walls appear to be quite thin (wow!), so there is probably not a huge difference between ID and OD. Guessing the location of a human heart from the cutaway view that I linked to, I find an $r$ very close to the 45 cm that I originally estimated.
– Ben Crowell
3 hours ago
Ah, ok, the 3m is the base diameter of the retro/equipment module, not the crew capsule illustrated.
– Russell Borogove
3 hours ago
add a comment |Â
up vote
4
down vote
accepted
A more authoritative source than Wikipedia would be NASA's Gemini VII Mission Report. Starting on page 5-25, the anomaly is described, with the main effect being an uncontrolled roll peaking at somewhat less than one revolution per second rather than Wikipedia's yaw:
Separation from the GATV [Agena] occurred at 7:15:12.3 GET with thrusÂÂters ll and 12 firing for 6.6 seconds. Rates at this time were +3, -5, and -2 deg/sec in pitch, roll, and yaw, respectively. After separation, moderate hand-controller activity was present, although the direct mode was not sufficient to contain the roll rate. At 7:15:44.7 GET, the ACME bias power was inadvertantly removed, disÂÂabling the control system, and the roll rate increased to 296 deg/sec over the next three minutes, due to the uncontrolled firing of thruster 8, although short periods of intermittent or degraded thruster 8 performance appeared to exist.
The roll axis is of course the longitudinal axis of the spacecraft; a seated astronaut facing forward in the Gemini couch is looking parallel to the roll axis.
The Gemini cockpit was quite cramped; picture the front seats of a small roadster, not an SUV. The couches are canted slightly apart from each other:
...so the roll axis passes not far from each astronaut's inboard hip -- your 45cm axis-to-heart estimate seems plausible, though with a high roll rate, excessive blood flow to the head would seem the more pressing problem, and the radius of concern might be more like 1 meter (the spacecraft being 3m in diameter)... although, mumble, acceleration gradient, calculus, grumble grumble
The crew debriefing document is also available, with more subjective impressions of the incident; Armstrong and Scott mention yaw but confirm the primary mode was roll:
Armstrong: Shortly after backing off, we noticed that we were essentially losing control of the spacecraft in roll and yaw and we suspected that we were over the life time of these attitude thrusters. The spacecraft was continuing, however, to accelerate, and we were obÂÂtaining rates in roll at least that approached 200 to
300 degrees per second, or perhaps more.
Scott: Yes, I would agree with that. It looked like even more to me, and it was by far more in roll than in yaw. The roll was the most predominate. [sic]
Armstrong: We realized that physiological limits were being apÂÂproached, and that we were going to have to do someÂÂthing immediately, in order to salvage the situation.
(You’ve got to love that professional detachment!)
answered 4 hours ago
Russell Borogove
72.9k2227311
Very nice write-up!
– Organic Marble
3 hours ago
Excellent answer, thanks! I've edited WP to change all the references to "yaw" into references to "roll." (Maybe someone else could do a more nuanced and careful edit to WP.) This seems like a perfect answer except for the lack of more authoritative/better sourced info on the physiology. I would think that the difference in (fictitious) gravitational potential between heard and brain would be the important number...? It's unfortunate that the diagram doesn't have a scale. Would the circle be 3 m? Is the 3 m an inside diameter? It was a cone, right?
– Ben Crowell
3 hours ago
Yeah, I've got no idea what the intersection of calculus and physiology is there; if you're making it a physics class problem you might just stop at "what's the radial acceleration at Armstrong's heart" (or head) and leave the health implications vague. :)
– Russell Borogove
3 hours ago
Based on this diagram space1.com/Spacecraft_Data/Handbook_Illustrations/Gemini/… , I think the circle on the figure you reproduced probably has a diameter of about 88 inches. The walls appear to be quite thin (wow!), so there is probably not a huge difference between ID and OD. Guessing the location of a human heart from the cutaway view that I linked to, I find an $r$ very close to the 45 cm that I originally estimated.
– Ben Crowell
3 hours ago
Ah, ok, the 3m is the base diameter of the retro/equipment module, not the crew capsule illustrated.
– Russell Borogove
3 hours ago
add a comment |Â
up vote
4
down vote
accepted
up vote
4
down vote
accepted
A more authoritative source than Wikipedia would be NASA's Gemini VII Mission Report. Starting on page 5-25, the anomaly is described, with the main effect being an uncontrolled roll peaking at somewhat less than one revolution per second rather than Wikipedia's yaw:
Separation from the GATV [Agena] occurred at 7:15:12.3 GET with thrusÂÂters ll and 12 firing for 6.6 seconds. Rates at this time were +3, -5, and -2 deg/sec in pitch, roll, and yaw, respectively. After separation, moderate hand-controller activity was present, although the direct mode was not sufficient to contain the roll rate. At 7:15:44.7 GET, the ACME bias power was inadvertantly removed, disÂÂabling the control system, and the roll rate increased to 296 deg/sec over the next three minutes, due to the uncontrolled firing of thruster 8, although short periods of intermittent or degraded thruster 8 performance appeared to exist.
The roll axis is of course the longitudinal axis of the spacecraft; a seated astronaut facing forward in the Gemini couch is looking parallel to the roll axis.
The Gemini cockpit was quite cramped; picture the front seats of a small roadster, not an SUV. The couches are canted slightly apart from each other:
...so the roll axis passes not far from each astronaut's inboard hip -- your 45cm axis-to-heart estimate seems plausible, though with a high roll rate, excessive blood flow to the head would seem the more pressing problem, and the radius of concern might be more like 1 meter (the spacecraft being 3m in diameter)... although, mumble, acceleration gradient, calculus, grumble grumble
The crew debriefing document is also available, with more subjective impressions of the incident; Armstrong and Scott mention yaw but confirm the primary mode was roll:
Armstrong: Shortly after backing off, we noticed that we were essentially losing control of the spacecraft in roll and yaw and we suspected that we were over the life time of these attitude thrusters. The spacecraft was continuing, however, to accelerate, and we were obÂÂtaining rates in roll at least that approached 200 to
300 degrees per second, or perhaps more.
Scott: Yes, I would agree with that. It looked like even more to me, and it was by far more in roll than in yaw. The roll was the most predominate. [sic]
Armstrong: We realized that physiological limits were being apÂÂproached, and that we were going to have to do someÂÂthing immediately, in order to salvage the situation.
(You’ve got to love that professional detachment!)
answered 4 hours ago
Russell Borogove
72.9k2227311
A more authoritative source than Wikipedia would be NASA's Gemini VII Mission Report. Starting on page 5-25, the anomaly is described, with the main effect being an uncontrolled roll peaking at somewhat less than one revolution per second rather than Wikipedia's yaw:
Separation from the GATV [Agena] occurred at 7:15:12.3 GET with thrusÂÂters ll and 12 firing for 6.6 seconds. Rates at this time were +3, -5, and -2 deg/sec in pitch, roll, and yaw, respectively. After separation, moderate hand-controller activity was present, although the direct mode was not sufficient to contain the roll rate. At 7:15:44.7 GET, the ACME bias power was inadvertantly removed, disÂÂabling the control system, and the roll rate increased to 296 deg/sec over the next three minutes, due to the uncontrolled firing of thruster 8, although short periods of intermittent or degraded thruster 8 performance appeared to exist.
The roll axis is of course the longitudinal axis of the spacecraft; a seated astronaut facing forward in the Gemini couch is looking parallel to the roll axis.
The Gemini cockpit was quite cramped; picture the front seats of a small roadster, not an SUV. The couches are canted slightly apart from each other:
...so the roll axis passes not far from each astronaut's inboard hip -- your 45cm axis-to-heart estimate seems plausible, though with a high roll rate, excessive blood flow to the head would seem the more pressing problem, and the radius of concern might be more like 1 meter (the spacecraft being 3m in diameter)... although, mumble, acceleration gradient, calculus, grumble grumble
The crew debriefing document is also available, with more subjective impressions of the incident; Armstrong and Scott mention yaw but confirm the primary mode was roll:
Armstrong: Shortly after backing off, we noticed that we were essentially losing control of the spacecraft in roll and yaw and we suspected that we were over the life time of these attitude thrusters. The spacecraft was continuing, however, to accelerate, and we were obÂÂtaining rates in roll at least that approached 200 to
300 degrees per second, or perhaps more.
Scott: Yes, I would agree with that. It looked like even more to me, and it was by far more in roll than in yaw. The roll was the most predominate. [sic]
Armstrong: We realized that physiological limits were being apÂÂproached, and that we were going to have to do someÂÂthing immediately, in order to salvage the situation.
(You’ve got to love that professional detachment!)
answered 4 hours ago
Russell Borogove
72.9k2227311
edited 3 hours ago
answered 4 hours ago
Russell Borogove
72.9k2227311
answered 4 hours ago
Russell Borogove
72.9k2227311
answered 4 hours ago
Russell Borogove
72.9k2227311
72.9k2227311
Very nice write-up!
– Organic Marble
3 hours ago
Excellent answer, thanks! I've edited WP to change all the references to "yaw" into references to "roll." (Maybe someone else could do a more nuanced and careful edit to WP.) This seems like a perfect answer except for the lack of more authoritative/better sourced info on the physiology. I would think that the difference in (fictitious) gravitational potential between heard and brain would be the important number...? It's unfortunate that the diagram doesn't have a scale. Would the circle be 3 m? Is the 3 m an inside diameter? It was a cone, right?
– Ben Crowell
3 hours ago
Yeah, I've got no idea what the intersection of calculus and physiology is there; if you're making it a physics class problem you might just stop at "what's the radial acceleration at Armstrong's heart" (or head) and leave the health implications vague. :)
– Russell Borogove
3 hours ago
Based on this diagram space1.com/Spacecraft_Data/Handbook_Illustrations/Gemini/… , I think the circle on the figure you reproduced probably has a diameter of about 88 inches. The walls appear to be quite thin (wow!), so there is probably not a huge difference between ID and OD. Guessing the location of a human heart from the cutaway view that I linked to, I find an $r$ very close to the 45 cm that I originally estimated.
– Ben Crowell
3 hours ago
Ah, ok, the 3m is the base diameter of the retro/equipment module, not the crew capsule illustrated.
– Russell Borogove
3 hours ago
add a comment |Â
Very nice write-up!
– Organic Marble
3 hours ago
Excellent answer, thanks! I've edited WP to change all the references to "yaw" into references to "roll." (Maybe someone else could do a more nuanced and careful edit to WP.) This seems like a perfect answer except for the lack of more authoritative/better sourced info on the physiology. I would think that the difference in (fictitious) gravitational potential between heard and brain would be the important number...? It's unfortunate that the diagram doesn't have a scale. Would the circle be 3 m? Is the 3 m an inside diameter? It was a cone, right?
– Ben Crowell
3 hours ago
Yeah, I've got no idea what the intersection of calculus and physiology is there; if you're making it a physics class problem you might just stop at "what's the radial acceleration at Armstrong's heart" (or head) and leave the health implications vague. :)
– Russell Borogove
3 hours ago
Based on this diagram space1.com/Spacecraft_Data/Handbook_Illustrations/Gemini/… , I think the circle on the figure you reproduced probably has a diameter of about 88 inches. The walls appear to be quite thin (wow!), so there is probably not a huge difference between ID and OD. Guessing the location of a human heart from the cutaway view that I linked to, I find an $r$ very close to the 45 cm that I originally estimated.
– Ben Crowell
3 hours ago
Ah, ok, the 3m is the base diameter of the retro/equipment module, not the crew capsule illustrated.
– Russell Borogove
3 hours ago
Very nice write-up!
– Organic Marble
3 hours ago
Very nice write-up!
– Organic Marble
3 hours ago
Excellent answer, thanks! I've edited WP to change all the references to "yaw" into references to "roll." (Maybe someone else could do a more nuanced and careful edit to WP.) This seems like a perfect answer except for the lack of more authoritative/better sourced info on the physiology. I would think that the difference in (fictitious) gravitational potential between heard and brain would be the important number...? It's unfortunate that the diagram doesn't have a scale. Would the circle be 3 m? Is the 3 m an inside diameter? It was a cone, right?
– Ben Crowell
3 hours ago
Excellent answer, thanks! I've edited WP to change all the references to "yaw" into references to "roll." (Maybe someone else could do a more nuanced and careful edit to WP.) This seems like a perfect answer except for the lack of more authoritative/better sourced info on the physiology. I would think that the difference in (fictitious) gravitational potential between heard and brain would be the important number...? It's unfortunate that the diagram doesn't have a scale. Would the circle be 3 m? Is the 3 m an inside diameter? It was a cone, right?
– Ben Crowell
3 hours ago
Yeah, I've got no idea what the intersection of calculus and physiology is there; if you're making it a physics class problem you might just stop at "what's the radial acceleration at Armstrong's heart" (or head) and leave the health implications vague. :)
– Russell Borogove
3 hours ago
Yeah, I've got no idea what the intersection of calculus and physiology is there; if you're making it a physics class problem you might just stop at "what's the radial acceleration at Armstrong's heart" (or head) and leave the health implications vague. :)
– Russell Borogove
3 hours ago
Based on this diagram space1.com/Spacecraft_Data/Handbook_Illustrations/Gemini/… , I think the circle on the figure you reproduced probably has a diameter of about 88 inches. The walls appear to be quite thin (wow!), so there is probably not a huge difference between ID and OD. Guessing the location of a human heart from the cutaway view that I linked to, I find an $r$ very close to the 45 cm that I originally estimated.
– Ben Crowell
3 hours ago
Based on this diagram space1.com/Spacecraft_Data/Handbook_Illustrations/Gemini/… , I think the circle on the figure you reproduced probably has a diameter of about 88 inches. The walls appear to be quite thin (wow!), so there is probably not a huge difference between ID and OD. Guessing the location of a human heart from the cutaway view that I linked to, I find an $r$ very close to the 45 cm that I originally estimated.
– Ben Crowell
3 hours ago
Ah, ok, the 3m is the base diameter of the retro/equipment module, not the crew capsule illustrated.
– Russell Borogove
3 hours ago
Ah, ok, the 3m is the base diameter of the retro/equipment module, not the crew capsule illustrated.
– Russell Borogove
3 hours ago
add a comment |Â
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fspace.stackexchange.com%2fquestions%2f31322%2facceleration-due-to-uncontrolled-rotation-of-gemini-8%23new-answer', 'question_page');
);
Post as a guest
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
