ISS Expands (2009 April 6)

[orin stepanek]

http://apod.nasa.gov/apod/ap090406.html

It makes a good background. 8)

Makes one wonder; why not make a Space wheel? As long as they keep adding on; make a wheel bit by bit. That way when they completed a circle they could get the wheel to spinning and have artificial gravity. I'm sure there would be some problems to be solved; but with today's technology; I'm sure it's doable. Maybe a little too scifi?

Orin

[apodman]

I like the wheel. You would have to keep it symmetrical and balanced as you build it to keep it rotating on center. That way the spinning could start before completion. I also favor a sort of merry-go-round (minus the horses) with a floor tilted toward the center to supplement the natural gravity when building facilities on the Moon and Mars. A round dome would fit perfectly over it, and you could use the rotational inertia for a drilling rig for mining operations. Thanks for making me spill the setup for another unwritten piece of sci-fi.

[Chris Peterson]

Makes one wonder; why not make a Space wheel? As long as they keep adding on; make a wheel bit by bit. That way when they completed a circle they could get the wheel to spinning and have artificial gravity. I'm sure there would be some problems to be solved; but with today's technology; I'm sure it's doable. :)

Don't underestimate the engineering challenges. They seem to have plenty of problems just maintaining the current structure. And a circle would require much more effort to construct (probably less pre-fab), and it would be harder to work on. And keep in mind that the primary science goals for the ISS (such as they are) are mainly microgravity experiments. A very small spinning section for astronaut health reasons might make sense, but that's all.

[apodman]

A very small spinning section for astronaut health reasons might make sense

If it's me up there, I want to live in a spinning section with the greatest possible radius. I'm not sure what effect the artificial tidal forces that come with a small radius would do to me. (The force pushing/pulling down at my feet would be appreciably larger than the force pushing/pulling down on my head.)

[Chris Peterson]

A very small spinning section for astronaut health reasons might make sense

If it's me up there, I want to live in a spinning section with the greatest possible radius. I'm not sure what effect the artificial tidal forces that come with a small radius would do to me. (The force pushing/pulling down at my feet would be appreciably larger than the force pushing/pulling down on my head.)

I didn't mean it had to be a hamster wheel <g>. I just meant small in terms of the total volume of the ISS. If most of the station isn't a microgravity environment, it kind of defeats the (purported) purpose of the thing.

[orin stepanek]

I like the concept of a wheel! It doesn't have to replace the ISS and it's mission; but in the future I think a permanent space station wheel may be the way to go. As space exploration expands it could serve as a jumping off spot. But who knows; in the future new propulsion methods may make a space station unnecessary.

Orin

[BMAONE23]

Chris,
I like your idea of a small spinning section for Astronaut health and habitation. It would likely take two small spinning sectione though. Spinning either in opposite directions on opposing sides of the station. Otherwise, you might get the crew quarters spinning in one direction and the remaining structure spinning in the opposite direction.

[neufer]

I like the concept of a wheel! It doesn't have to replace the ISS and it's mission; but in the future I think a permanent space station wheel may be the way to go. As space exploration expands it could serve as a jumping off spot. But who knows; in the future new propulsion methods may make a space station unnecessary.

<<A rotating wheel space station is a hypothetical wheel-shaped space station that could create artificial gravity by rotating. If the station were rotated at the correct speed, centrifugal force would cause objects to gravitate toward the outer rim of the 'wheel'.

Both scientists and science fiction writers have thought about this concept since the beginning of the 20th Century. Konstantin Tsiolkovsky wrote about using rotation to create an artificial gravity in space in 1903. Hermann Noordung introduced a spinning wheel station with a 30 meter diameter in his Problem der Befahrung des Weltraums (The Problem of Space Faring). He even suggested it be placed in a geostationary orbit.

In the 1950s, Wernher von Braun and Willy Ley, writing in Colliers Magazine, updated the idea, in part as a way to stage spacecraft headed for Mars. They envisioned a rotating wheel with a diameter of 76 meters (250 feet). The 3-deck wheel would revolve at 3 RPM to provide artificial one-third gravity. It was envisaged as having a crew of 80.

In 1959, a NASA committee opined that a such a space station was the next logical step after the Mercury program. The Stanford torus, proposed by NASA in 1975, is an enormous version of the same concept, that could harbor an entire city.

NASA has never attempted to build a rotating wheel space station, for several reasons. First, such a station would be very difficult to construct, given the limited lifting capability available to the United States and other spacefaring nations. Assembling such a station and pressurizing it would present formidable obstacles, which, though not beyond NASA's technical capability, would be beyond available budgets. Second, NASA considers its present space station, the ISS, to be valuable as a zero gravity laboratory, and its current microgravity environment was a conscious choice.>>

A famous fictional space station of this kind is Space Station V, which appears in the film 2001: A Space Odyssey.>>

-------------------------------------------------------

.
<<Herman Potočnik (pseudonym Hermann Noordung) (December 22, 1892 - August 27, 1929) was a Slovene rocket engineer and pioneer of cosmonautics (astronautics). The meaning of his German-like pseudonym Noordung is still a mystery, but some suggest that he used it to show the problems of chaos (German: Ordnung). Assuming that the initial "N" may have been intended to stand as a negation, the name would mean "without order" or "no order".
.
Potočnik was born in Pula, southern Istria, Austria-Hungary (now Pula, Croatia). His father Jožef was born in 1841 in Zgornji Razbor near Slovenj Gradec and at the time of Herman's birth he served as a doctor and high navy officer in the Austro-Hungarian Navy harbour of Pula. His mother Minka was born February 7, 1854. She was a descendant of Czech immigrants, manufacturers of crucibles for glass-making and a daughter of a well known wine merchant and local councillor Jožef Kokošinek from Maribor, later also Vitanje. Father Jožef in 1866 participated in the second Battle of Vis, where Austro-Hungarian Navy under command of von Tegetthoff defeated Royal Italian Navy commanded by Count di Persano. Jožef was later a general in Austro-Hungarian Army. When Herman's father died in 1894, his mother moved the family to Maribor (at that time also officially named Marburg). Herman had two brothers Adolf and Gustav (who were both navy officers), and a sister Franci. He spent most of his childhood years in Maribor and Vitanje. In Maribor Potočnik attended primary school.
.
During the World War I he served in Galicia, Serbia and Bosnia and in 1915 he was promoted to the rank of First Lieutenant (Oberleutnant). He was assigned to the southwestern front of the Soča battlefield and there he experienced a breakthrough of Austrian army to the river Piava and its retreat. In 1919 he was pensioned off from the Austrian military with the rank of Captain because of tuberculosis that he got during the war. He started to study electrical engineering in the mechanical engineering department of the University of Technology in Vienna. Being awarded a doctorate in engineering, he specialised in rocketry, and from 1925 he devoted himself entirely to the problems of a rocket science and space technology. Owing to chronic illness, he did not find a job or marry, but lived with his brother Adolf in Vienna.
.
At the end of 1928, he published his sole book, Das Problem der Befahrung des Weltraums - der Raketen-Motor (The Problem of Space Travel - The Rocket Motor) in Berlin. The publisher, Richard Carl Schmidt, printed the year 1929 as a publishing date, probably from a purely business motive (to keep the book looking new throughout the coming year) and this date is often mistakenly given as the actual date of publication. In 188 pages and 100 handmade illustrations, Potočnik set out a plan for a breakthrough into space and the establishment of a permanent human presence there. He conceived a space station in detail and was the first man to calculate the geostationary orbit, on which the station would orbit the Earth. He described the use of orbiting spacecraft for detailed observation of the ground for peaceful and military purposes, and described how the special conditions of space could be useful for scientific experiments. Potočnik expressed strong doubts of the potentially destructive military use of these fresh discoveries.
.
The book was translated into Russian in early 1935, Slovene in 1986 (by the Slovenska matica), English in 1999 (by NASA) and Croatian in 2004 (by Marino Fonović, published by Labin Art Press). A partial translation in English, containing most of the essential chapters, was made as early as 1929 for the american magazine Science Wonder Stories and was issued in three parts.
.
With his many ideas he became one of the founders of astronautics. His concepts were first taken seriously only by the amateur rocketry movement in Germany, the Verein für Raumschiffahrt (VfR - "Spaceflight Society"), centered on Hermann Oberth and his co-workers. In its Russian edition, the book may also have influenced Sergey Korolev's circle. More locally, Viennese engineers dismissed his work as fantasy.
.
Potočnik's book described geostationary satellites (first put forward by Konstantin Tsiolkovsky) and discussed communication between them and the ground using radio, but fell short of the idea of using satellites for mass broadcasting and as telecommunications relays (developed by Arthur C. Clarke in his Wireless World article of 1945). The wheel-shaped space station served as an inspiration for further development by Wernher von Braun (another former VfR member) in 1953. Von Braun saw orbiting space stations as a stepping stone to travel to other planets. In 1968, Stanley Kubrick's ground-breaking film, 2001: A Space Odyssey, depicted such a role for "Space Station V."
.
Potočnik died of pneumonia at the age of 36 in great poverty, in Vienna, Austria and was buried there. An obituary notice about his death was printed in one Maribor daily newspaper, mentioning his ranks (engineers and captain), his illness and nothing about his work about space.>>

---------------------------------------

[orin stepanek]

There's no rule that says that the space station would have to be a perfect circle; as long as it was in perfect balance, it could turn and create gravity. A hexagon or octagon shape or similar structure would work. A hub with spokes and equal weight compartments on opposite ends would work. That would keep it simple and work just as good as a perfect wheel. Of course I'm not talking about micro gravity experiments; but rather as a stepping stone for future space exploration.

Orin

[neufer]

There's no rule that says that the space station would have to be a perfect circle; as long as it was in perfect balance, it could turn and create gravity. A hexagon or octagon shape or similar structure would work. A hub with spokes and equal weight compartments on opposite ends would work. That would keep it simple and work just as good as a perfect wheel. Of course I'm not talking about micro gravity experiments; but rather as a stepping stone for future space exploration.

• "Garn" tootin' !

-----------------------------------------------------------------------

• Health effects of weightlessness
  
  <<Following the advent of space stations that can be inhabited for long periods of time, exposure to weightlessness has been demonstrated to have some deleterious effects on human health. Humans are well-adapted to the physical conditions at the surface of the Earth. In response to an extended period of weightlessness, various physiological systems begin to change and atrophy. Though these changes are usually temporary, long term health issues can result.
  
  The most common problem experienced by humans in the initial hours of weightlessness is known as space adaptation syndrome or SAS, commonly referred to as space sickness. Symptoms of SAS include nausea and vomiting, vertigo, headaches, lethargy, and overall malaise. The first case of SAS was reported by cosmonaut Gherman Titov in 1961. Since then, roughly 45% of all people who have flown in space have suffered from this condition. The duration of space sickness varies, but in no case has it lasted for more than 72 hours, after which the body adjusts to the new environment. NASA jokingly measures SAS using the "Garn scale", named for United States Senator Jake Garn, whose SAS during STS-51-D was the worst on record. Accordingly, one "Garn" is equivalent to the most severe possible case of SAS.
  
  The most significant adverse effects of long-term weightlessness are muscle atrophy and deterioration of the skeleton, or spaceflight osteopenia. These effects can be minimized through a regimen of exercise. Other significant effects include fluid redistribution, a slowing of the cardiovascular system, decreased production of red blood cells, balance disorders, and a weakening of the immune system. Lesser symptoms include loss of body mass, nasal congestion, sleep disturbance, excess flatulence, and puffiness of the face. These effects begin to reverse quickly upon return to the Earth.
  
  Many of the conditions caused by exposure to weightlessness are similar to those resulting from aging. Scientists believe that studies of the detrimental effects of weightlessness could have medical benefits, such as a possible treatment for osteoporosis and improved medical care for the bed-ridden and elderly.>>
  ..............................................
  . Effects on non-human organisms
  
  <<Russian scientists have observed differences between cockroaches conceived in space and their terrestrial counterparts.
  The space-conceived cockroaches grew more quickly, and also grew up to be faster and tougher.>>
  
  Agent K (Tommy Lee Jones) : Imagine a giant cockroach, with unlimited strength, a massive inferiority complex, and a real short temper, is terror-assing around Manhattan Island in a brand-new Edgar suit. That sound like fun?
  
  Agent K : I've just been down the gullet of an interstellar cockroach. That's one of a hundred memories I don't want.

-------------------------------------------

<<Candle flames were studied on the Mir Space Station. This candle flame is very different from what we see on Earth. A flame on Earth takes on a pear-like shape positioned over the wick, which is different than this flame on the Mir that surrounds the wick. Flame flickering, flame oscillations, and gravitational effects were studied for the candle flame experiment.>>

[rigelan]

There's no rule that says that the space station would have to be a perfect circle; as long as it was in perfect balance, it could turn and create gravity. A hexagon or octagon shape or similar structure would work. A hub with spokes and equal weight compartments on opposite ends would work. That would keep it simple and work just as good as a perfect wheel. Of course I'm not talking about micro gravity experiments; but rather as a stepping stone for future space exploration.

Orin

You are correct, there is no rule that it needs to be circular. But a perfectly circular one would have constant gravity on the floor of the wheel, which an octagon would have different strengths of gravity, depending upon which part of the octagon you were on.

[neufer]

There's no rule that says that the space station would have to be a perfect circle;
as long as it was in perfect balance, it could turn and create gravity.

How would they keep "perfect balance" all the time?
Any "all hands meeting" at one end of the space station
would cause one hell of a WOBBLE!
--------------------------------------------------------------------
Miguel de Cervantes » Don Quixote Part II» Chapter XLI
OF THE ARRIVAL OF CLAVILENO AND THE END OF THIS PROTRACTED ADVENTURE

They were then blindfolded, and Don Quixote, finding himself settled
to his satisfaction, felt for the peg, and the instant he placed his
fingers on it, all the duennas and all who stood by lifted up their
voices exclaiming, "God guide thee, valiant knight! God be with
thee, intrepid squire! Now, now ye go cleaving the air more swiftly
than an arrow! Now ye begin to amaze and astonish all who are gazing
at you from the earth! Take care not to WOBBLE about, valiant
Sancho! Mind thou fall not, for thy fall will be worse than that
rash youth's who tried to steer the chariot of his father the Sun!"
--------------------------------------------------------------------

A hexagon or octagon shape or similar structure would work. A hub with spokes and equal weight compartments on opposite ends would work. That would keep it simple and work just as good as a perfect wheel.

You are correct, there is no rule that it needs to be circular. But a perfectly circular one would have constant gravity on the floor of the wheel, which an octagon would have different strengths of gravity, depending upon which part of the octagon you were on.

But, with a little practice, one might even get by with a rectangle:
http://www.youtube.com/watch?v=kWUtW_tM ... =quicklist

[apodman]

How would they keep "perfect balance" all the time? Any "all hands meeting" at one end of the space station
would cause one hell of a WOBBLE!

Tall buildings use mobile masses near the top to counteract and dampen wind sway. Telescopes use incredibly fast and responsive adaptive optics to detect and counteract the effects of atmospheric turbulence. Combining elements from these two technologies, quickly detecting and compensating for changes in balance, is well within our capabilities. And remember, cost is no object.

[Chris Peterson]

How would they keep "perfect balance" all the time? Any "all hands meeting" at one end of the space station
would cause one hell of a WOBBLE!

Tall buildings use mobile masses near the top to counteract and dampen wind sway. Telescopes use incredibly fast and responsive adaptive optics to detect and counteract the effects of atmospheric turbulence. Combining elements from these two technologies, quickly detecting and compensating for changes in balance, is well within our capabilities. And remember, cost is no object.

That seems to be making things a lot more complicated than necessary. All you need is a rotating boom, with a room at one end and a counterweight at the other. The counterweight can be shifted slightly to compensate for different masses in the room. That system is intrinsically stable, and would introduce no wobble. A minimal control system is all that would be required.

That said, even such a simple centrifuge design still poses major engineering hurtles in terms of fabrication and maintenance.