Yep, no idea whether such beacons are even possible. I can't remember where I read about it, and I don't know how much fissile material it would take to alter the spectrum. Probably a huge amount. Well, if we achieve fusion power, I guess there will be a lot of leftover Uranium to use for this purpose. Shooting raw Uranium ore into the Sun might indicate to the observer that fusion power has been achieved as well.

I guess it does make more sense to permanently alter the spectrum, perhaps by throwing asteroids with high metal content into the Sun continuously, which surely a Kardashev-level II civilization could do, but then you'd have the problem of variations in the spectral emissions that might just look random to an observer, even assuming they were continuously monitoring the star. Also, the K-II civilization might not be blessed (cursed?) with the incredibly large number of asteroids that we have, or may wish to use them for mining.

> Any life out there capable of generating a signal that could be detected at interstellar distances is likely far more advanced than us, certainly those capable of modulating their sun are, and may quite possibly have discovered technologies much better suited to interstellar communication than radio or optics.

Indeed, solutions 9-30 in Webb's book deal with these possibilities.

You make some good points. Thanks for the reply.

Many of the issues in these threads are discussed in the excellent book Where is Everybody?, which provides fifty solutions to Fermi's Paradox of why the Universe is not teeming with intelligent life.

However, you make an excellent point regarding the recent Heliopause discoveries, which occurred well after Stephen Webb's book came out in 2002. You might want to get in touch with the author and share your insight. I couldn't find an email address for him.

There's only one solution I can think of to the issue of RF transmissions being masked by the Heliopause. And that would be altering the spectrum of the Sun in a recognizable pattern.

For example, shooting a large (like, ridiculously large) amount of nuclear waste into the Sun might cause an alien spectral analysis to show an unexpected band of ionized depleted Uranium along with other elements in spent fuel. If that band appeared and disappeared yearly in a prime number or Fibonacci sequence, an alien astronomer with our level of technology or greater would be able to deduce:

1. The length of the Earth year and, I presume, the distance from the Sun to the Earth if they have their own Kepler mission.

2. The fact that Earth has achieved fission but not fusion nuclear power and related technologies.

3. That Earth has not yet annihilated itself through the discovery of nuclear technology.

4. That Earth is ready to receive a strong, directed communication that can penetrate the Heliopause.

5. What form of communication should be used to send the signal to Earth given the technology it possessed at the time the signal was initially transmitted. Perhaps that would involve altering their own star's spectrum if RF is impossible.

And many other facts.

However, there is a problem. No one seems to have done this yet. If it were possible, surely we would have seen such a beacon by now in all of our spectral analyses of all of the stars visible to us in the Universe.

Unfortunately, that would support solution number 50 in Webb's book: The Rare Earth. Sad, but apparently true at this time.

If we are going to propagate throughout the Galaxy, as we must do anyway to ensure survival within the next billion years before the Sun boils off the Earth's atmosphere, it looks like our civilization will be the one that solve's Fermi's paradox.

> What would happen if you paid for 80 litres of fuel but you only needed 70 to brim the tank?

You go back to the attendant and he or she gives you change. It's pretty easy.

> I gained an amazing vocabulary of dirty words and depraved acts from printed material when I was a kid, but I didn't know how to properly apply them til my dad taught me.

Hmm....how closely did your dad supervise you in this training regimen you describe? ;)

It's called the Puritan Heritage. Sad but true: check this brief summary out.

Europe will never get it; it's too ingrained in American culture that violence is OK but sex is not.

There is one benefit, however. Judging by the horribly embarrassing percentage of America that is obese or otherwise unsuitable for being seen naked, I am actually more comfortable with how we do things over here.

I especially don't like the "whores in windows" in Amsterdam, although prostitution is legal in a small part of the U.S. so I can't really complain about it being legal over there. Sex toys in windows, more of a gray area. I'd rather not see them but that's just my opinion.

> The reason for private citizens to own guns is so we can execute corrupt police, tyrannical senators and presidents, and (oh yeah, way way down on the list) muggers.

What are you, your own lynch mob? The constitution also provides that no person shall be deprived of life or liberty without due process of law. Granted, the 5th Amendment has been read to apply to the government and not to private actors. However, certainly an elected official would be entitled to due process of law from any transitional government purporting to replace his own, regardless of how severely the new government might disagree with his or her policies or acts while in office. Even Saddam received a trial. Even the Nuremburg defendants received a trial. Even Civil War prisoners in the U.S. were treated as prisoners of war with the rights that that entailed at the time, rather than being executed for treason as would have been expressly permitted by the constitution. Entire books have been written about victor's justice and whether it can ever be fair-- or perceived to be fair. What is certainly not fair is for a private citizen or group of private citizens to decide on his/her/their own that a government official deserves to be executed for official acts.

Yes, I would have a problem with someone unilaterally executing Hugo Chavez, even though his regime does not afford the very due process he would receive. I happen to believe it was a huge mistake to execute Bin Laden when he clearly could have been captured alive and interrogated concerning al Qaeda's strategic plans, and then tried and convicted under our very own system of laws, and then put to death for his terrible crimes.

Regardless of any disagreement we may have over Bin Laden, who in any event was not an elected official, it is inconsistent with the principles expressed in the U.S. constitution for lynch mobs to simply execute public officials whom they believe to be corrupt.

Muggers are fair game though. Do you see a difference between killing a mugger in self-defense and executing an elected official? I do, I really do, and I hope that other gun owners do as well.