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Spacewalk optional If you have just purchased your trip to Space Station Alpha from Space Adventures for $20M and still have money burning a hole in your pocket, you can now take a walk in space for a mere $15M extra.
According to Astronaut Tom Jones:
During a 90-minute EVA, which is the time it takes the ISS to make one complete orbit around Earth, a spacewalker would experience orbital sunrise and sunset, Jones said.
“That 90 minutes is like gold to a real spacewalkers,” Jones said. “I got a total of five or 10 minutes of doing that in my 19 hours in terms of just unstructured time, so it’s literally that precious an experience.”
Now if my next venture works out and makes me a billionaire…
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So Dale,
I seem to recall that in orbit, that which faces the sun will heat to something like +250 F while the self same object’s shaded side will cool to -250 F. Assuming my memory is correct, do we really have the technology to allow someone to enjoy a 90 minute EVA without ending up roasted on one side and deep frozen on the other?
I defer to your superior familiarity on the topic….
Heard this one on the radio the other day….
Oh yeah, me too. Hit the lottery big and I’m there.
As for the heating and cooling…you should be able to stay in the shade. One would think that for $15 million, they’ve got that figured out.
Yeah, the spacesuits are, beyond pressurization, almost completely given over to thermal control, with liquid coolant and ventilation. They’d have to, even under normal conditions, given how much heat the human body emits.
First off, an existence proof: astronanuts are regularing working 6 to 8 hours outside of Alpha. QED.
Now more physics of it. I am not certain of your temperature numbers and would have to go digging. I know there is about 1360 watts / sq m normal to the sun, but I’ll not go down that route because I’d have to crack a book to turn it into a temperature and it isn’t really necessary to answer your question.
Lets just call it very hot on the sun side and very cold on the shadow side.
Now, exactly what is it that is ‘very hot’ or ‘very cold’? Space is, to human senses, pretty much nothing, and nothing doesn’t really have a sensible temperature. When they speak of such, they mean the ‘blackbody’ temperature of an object in equilibrium with its surroundings. Blackbody means an object that absorbs all radiation impinging on it and then re-radiates at a lower frequency. Such an object, turned towards the sun in Earth’s orbit and would get very hot and stabilize. If we also had a perfectly insulated side (ie no heat flow from the front) facing away fro the sun, it would be absorbing radiation from the stars, planets, the Earth in particular and the moon. It will equilibrate at a very cold temperature.
There are useful for calculations and Physics tests, but man made objects in space tend to be a bit more complex. Space suits are not perfectly absorbing or perfectly radiating and in fact do not get very hot or cold due to the ambient radiation. The biggest problem in space suits (and may still be) is getting rid of the internally generated heat. A human being can be modeled as a 100w light bulb when at rest, and that output can go up a great deal when doing hard labour in space. That heat has to be rejected or the astronaut will cook themselves, or at least feel like they are living in St. Louis.
Not content with women throwing their underwear at him…
…Tom Jones also has to be an astronaut.
It’s truly amazing that the likes of me have a girlfriend at all.
As far as the comments on temprature are concerned. Well Dale is right about the blackbody thing. Space (even LEO) is a very hard vacuum so it is a moot point (and irrelevant for most practical purposes) to assign it a temperature. Having said that there are enormous heat transfers one way or another depending fundamentally on whether you’re sunward or not. Interstellar space is about 2.7K which is somewhat on the cold side although if you’re in the path of radiation from a nearby star then you’ll heat up nonetheless. Think of it as being in a very cold house with a single very powerful electric fire.
I first picked up this story from The Times Online. They also mention that a space suit costs GBP 6.5 million.
Tell ya what Dale. If my next venture makes me a billionaire, I’ll take you up too.