Yes, I remember that one. I seem to recall they didn't give it the final, correct answer until it was a safe distance away.

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Everything I need to know I learned through Googling.

Did Aliens have replied to another message?Hoax or reality you will be the judge.

The Arecibo message beamed into space in 1974 by Drake and Sagan represented in data pixel form...

http://www.eionews.addr.com/psyops/chilbolton_reply.htm

Add
http://www.swirlednews.com/article.asp?artID=260

Hoax.

Aporetic
www.polisci.wisc.edu/~rdparrish

Not an easy one.That is not only simple circles.How hoaxers can do the reply to the Aracibo message in one night?

There is a following
http://yowusa.com/Archive/May2003/cr.../crabwood4.htm

Add
http://www.eionews.addr.com/psyops/c...he_verdict.htm

This morning I had a bit of an idea about how to tell an alien society where our probe originated. I don't know if it is any good, but here it is:

When they encounter the probe it will likely be moving in some direction, probably the direction in which it was going when it left our solar system. If it isn't, that another story - probably one in which it was party to a collision, and is likely to be too damaged for any plaque or other means of communication to survive.

So assuming the craft is still travelling in roughly a direction that will point back here. But the line along which the craft travelled is a long one, so the aliens will need to know how far back along this line to search. They need a mission run-time clock of some sort, that they can follow back to Zero, given the craft's speed and direction of travel. It seems to me that radioactive decay might do the job.

It might work like this: We put X amount of a radioactive substance into the craft. It will do its decaying thing, and when the aliens encounter it they can reconstruct how long the craft has been travelling by determining the amount of time that it takes for the initial radioactive mass to decay to its current state.

Of course, the trick is to communicate the original mass of the radioactive substance. It seems to me that this can be done with relative ease (relative, that is, to some of the other actual or proposed plaques, etc.) by engraving a drawing of the mass in its initial state. This drawing would likely have to include individual atoms so that the aliens can count them. I don't think it would take as great a leap for them to understand this as it would for them to understand, for example, the pulsar image.

Aporetic
www.polisci.wisc.edu/~rdparrish

Don't all the probes that have left the solar system have plutonium on board already? And I don't think you'd need to identify the original mass: any reasonably sophisticated alien race should be able to identify the decay products. We manage it just fine when dating rocks.

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Everything I need to know I learned through Googling.

A lot of earlier satellites carried a radioactive isotope to keep the instruments warm (and accounts for the presence of a little plutonium in all of us from accidents where the material was spilled). Nowadays I believe they use electric heaters/radiators.
It's hard to assume that a probe would travel in a straight line, especially since we don't know what it is passing in the gravitational influence of. For all we know, some of our probes may be coming right back at us after slingshotting around some body.

Darnon

While grocery shopping a little while ago, I was thinking about that and other things that would cause the craft's path to change. I'm not sure what to do about that, except to include the pulsar triangulation plaque as well. It seems to me that if the aliens get into the general vicinity of Earth that they wouldn't have much trouble spotting us.

Or we could have all our probes trail a long wire behind them...

Aporetic
www.polisci.wisc.edu/~rdparrish

One could include several vials of (initially pure) radioisotopes of different halflifes, giving a graduated and overlapping time scale. One could start with Ra 226 (1499y), C14(5700y), Pu239(25.4Ky), Th230 (75.4Ky)... U238(4.46Gy).

Aliens decode the time of launch.
Aliens track the probe's path back that far and, voila only system in the vicinity.

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Any day you wake up on "the right side of the dirt" is a good day.

T. Anderson

Yes, but the power still has to come from somewhere. Every mission that's gone to Jupiter or beyond has had to use plutonium RTGs as a power source because solar cells (the only other possibility right now) just don't cut it that far away from the Sun.

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Everything I need to know I learned through Googling.

Actually, it's very easy to assume they would travel in a straight line, or at least close to straight. Space is very, very empty and the probes are travelling mighty fast. There's not much out there to perturb a trajectory. Unless an object were very big, or the encounter was very close, there wouldn't be more than a slight alteration in course. A 180° slingshot is all but impossible.

BTW, there has been a measured change, not in the courses, but in the speeds of Pioneer 10 and 11. I don't think the reason has been fully determined yet, but it doesn't seem to be due to encounters with unknown objects. (Here's one possible explanation I dug up.)

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...And that, my liege, is how we know the Earth to be banana-shaped. --Sir Bedevere

Interesting article, David, but I thought the decelleration had not been observed in the Voyagers...

earlier topic #1

earlier topic #2

earlier topic #3

The article I posted had this to say:

So, yeah. But I agree that the opening graphic is a bit misleading.

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...And that, my liege, is how we know the Earth to be banana-shaped. --Sir Bedevere

Hmm, I was referring to this article.

Oh, ok. But that one only refers to the Pioneers as well. Since it's impossible to measure the effect on the Voyagers, I suppose we simply cannot apply it to them, even if the effect is actually there.

Frankly, the page is a bit over my head anyway, so I really can't say much about it myself.

I've heard that the same (or similar) effect was measured on Galileo's trip out though, and one other, SOHO?. Maybe it would explain them too.

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...And that, my liege, is how we know the Earth to be banana-shaped. --Sir Bedevere

Will be Voyager say hello to Aliens? In about 70 years time a Russian, American, Euro or Chinese ship might be going out to the edge of our solar system to collect those Voyager craft and put them in a Museum

Like This??

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Orion's Arm . The Starlark . Voices: Future Tense- Novella Contest Issue! . OA Flickr set

A show based on the Voyager message:

The Earth: an introduction for aliens

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Everything I need to know I learned through Googling.

Actually, I thought Pioneer 10 was/will be destroyed by the Klingons!! 8-[

Maurice

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Why is it that in a traffic jam the other lane always moves faster?

I wrote a short story about this possibility. I wrote it in dutch, but I do have an english translation. It was no success, but I had a lot of fun writing it.

I also wrote a short story about a pioneer plaque, in that story the space probe is found by aliens (so without return to earth for a museum). If someone likes to read this one, you can find it here. It's on a german sf literature board but the story is in english (I had some help).

I believe I had the maths and theories behind both stories correct.