Detecting systems with life


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Profile William Rothamel
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Message 1132492 - Posted: 27 Jul 2011, 9:40:29 UTC - in response to Message 1132317.

What are the other ways of containing a fusion reaction that might allow fusion to power a spaceship other than a tokamak type of arrangement.

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Message 1132493 - Posted: 27 Jul 2011, 9:41:21 UTC - in response to Message 1132317.

There is more than one way of sustaining fusion in a reactor, other than magnets with superconducting coils.

Yes, the inertial confinement approach tried at Livermore National Laboratory, which makes H-bombs. But it uses high powered lasers and is not working yet. It is more an attempt to produce micro H-bomb explosions than producing power.
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Message 1132574 - Posted: 27 Jul 2011, 15:02:33 UTC - in response to Message 1132417.

A trip to the Alpha Centauri system in a craft going 30 light speed, for the experts outthere, how long would such a craft take to reach the Alpha Centauri system? do the math, a mere 4.5 light years away. I m refering to the binary system of Alpha Centauri, A and B. Even Gliese d, do the math.

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Message 1132917 - Posted: 28 Jul 2011, 9:28:28 UTC - in response to Message 1132574.

A trip to the Alpha Centauri system in a craft going 30 light speed, for the experts outthere, how long would such a craft take to reach the Alpha Centauri system? do the math, a mere 4.5 light years away. I m refering to the binary system of Alpha Centauri, A and B. Even Gliese d, do the math.

Are you asking 30 times the speed of light or 30% of the speed of light?
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Message 1132973 - Posted: 28 Jul 2011, 14:22:52 UTC - in response to Message 1132917.

oops sorry, i meant at 30% light speed.

Profile Gary Charpentier
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Message 1133004 - Posted: 28 Jul 2011, 15:40:26 UTC - in response to Message 1132973.

oops sorry, i meant at 30% light speed.

Actually what is more important is the rate of acceleration.

We don't instantly go from zero to 30% light or the reverse when we get to the destination. So you have the time and distance to accelerate at say 1g to your cruise speed, your coasting cruise until it is time to hit the brakes, and your deceleration time which matches your acceleration time. Good estimate but it ignores if the destination star system is moving relative to the sun system.

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Message 1133216 - Posted: 29 Jul 2011, 0:58:43 UTC - in response to Message 1133004.

thank you for the good information.

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Message 1133393 - Posted: 29 Jul 2011, 7:50:03 UTC

I haven't done the math but I do know at that rate by the time you got back to earth everyone you knew would be dead.
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Message 1133395 - Posted: 29 Jul 2011, 7:56:20 UTC

Not allowing for acceleration it would by my calculation take 285 yrs one way.
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Message 1133449 - Posted: 29 Jul 2011, 12:59:31 UTC

I think now I did some bad math and the time one way at 30% of lightspeed not allowing for acceleration or decelleration would be 15 years for the crew.
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Message 1133736 - Posted: 29 Jul 2011, 23:39:32 UTC - in response to Message 1133449.

Interesting, 15 years for astronauts to reach the Alpha Centauri system in a craft at 30 percent light speed. So to Gliese d, looking at 40 to 50 year space mission in such a craft. I could see a craft powered by nuclear pulse fusion doing such missions. That is something that NASA can focus on, nuclear pulse fusion research.

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Message 1133747 - Posted: 29 Jul 2011, 23:51:47 UTC

Question? can the Atacama Large Millimeter/submillimeter Array be used for the detection of radio signals that might be artificialin nature from the cosmos? Basically, can Atacama Large Millimeter/submillimeter Array be used like Arecibo?

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Message 1133960 - Posted: 30 Jul 2011, 5:38:26 UTC - in response to Message 1133747.

All I know is that a key person from the Allen Telescope Array has gone to Atacama. Maybe she can do something.
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Message 1136112 - Posted: 5 Aug 2011, 3:03:52 UTC - in response to Message 1133960.

Allen Array will up and running again

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Message 1136187 - Posted: 5 Aug 2011, 8:54:07 UTC

Yes, the inertial confinement approach tried at Livermore National Laboratory, which makes H-bombs. But it uses high powered lasers and is not working yet. It is more an attempt to produce micro H-bomb explosions than producing power.
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I used to canoe on the lake there in the Livermore valley. I have seen the TV show on the "Cold Fusion" project going on there. I hate to think that such a prestigious Laboratory would be doing anything that was not scientifically sound---but then there was PEAR at Princeton and JB Rhine and Parapsychology at Duke.

The cold fusion project there gives me that funny feeling. What do you think ?

The lasers were supposed to be turned on last summer.

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Message 1136230 - Posted: 5 Aug 2011, 13:22:59 UTC - in response to Message 1136187.

I don't think Livermore is looking into cold fusion.On June 24 there was an article on the NYTimes titled "Fusion experiment faces new hurdles".Its main point is that tritium used in the experiments can pollute the environment and cause lung cancer if inhaled. This was also the worry of the Nuclear Regulatory Commission about a sizable number of fission reactors in the USA. Tritium cannot be used as an explosive material but if you inhale it you are dead.
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Message 1136238 - Posted: 5 Aug 2011, 13:55:07 UTC - in response to Message 1136230.

Tritium is what makes your watch glow at night. It is also used in some medical applications. I think that we used to burn it in our power plant at the university where I worked by putting it into the #6 fuel oil tanks that fired the power plant at the time.

Radon gas can also cause lung cancer--it was fairly common in basements in New Jerseysince much of the state sits over the Redding Tongue of uranium rich rock.

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Message 1136245 - Posted: 5 Aug 2011, 14:26:20 UTC - in response to Message 1136238.


Radon gas can also cause lung cancer--it was fairly common in basements in New Jerseysince much of the state sits over the Redding Tongue of uranium rich rock.

I know. But in Badgastein, Austria, you can go into old mine tunnels to make "Radon baths". I am not joking, it was also on advertisement leaflets for that skiing resort (but only downhill runs, not my cross-country, so I did not return there).
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Message 1136254 - Posted: 5 Aug 2011, 14:38:32 UTC - in response to Message 1133449.

I think now I did some bad math and the time one way at 30% of lightspeed not allowing for acceleration or decelleration would be 15 years for the crew.

It's actually pretty good that it would be doable in the lifespan of a single crew. Otherwise (for further-away destinations) we have to go to the model of large "generation ships", where you actually have children born and raised in space, the parents dying of old age, etc., and the highly-trained (by then) children taking their place, etc., etc., until the round trip was completed. And of course, with time dilation, even more years would have passed on Earth by the time the ship returned... the argument always was that by the time any such ship made it back from its long, isolated journey, odds were that we'd have developed a level of tech sufficient to make the round trip much faster.
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Message 1136257 - Posted: 5 Aug 2011, 14:45:43 UTC

Cornwall UK has a problem because it is on granite.

Radon

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