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Making It Hard For Extraterrestrials To Hear Us
quaith writes "US astronomer Frank Drake has told scientists at a special SETI meeting in London that earthlings are making it less likely that we will be heard in space. In the past, we used huge ground stations to broadcast radio and television signals which could be picked up relatively easily — according to astronomers' calculations anyway. Now we use satellites that transmit at 75 watts and point toward Earth instead of into space. In addition, we've switched to digital which makes the transmissions even fainter. Drake has concluded that very soon, in space no one will hear us at all. I guess we'd better keep listening."
Silly humans... You shouldn't worry about whether other civilizations in distant star systems will detect your weak radio-spectrum emissions. That's isn't what we are scanning for in our extra-solar search.
In the beginning you humans signaled with visual signals - for example hand gestures, light houses, national flags, and road-side billboards. These are great but have very limited range.
Later you developed audio signaling for example speech, alarms, and air-raid horns. It has much further range and carries far more information, but degrades far more quickly over time.
Still later you developed electrical signaling devices, like the telegraph and early 1900's era telephone wire. You could finally transmit information over a long distance.
Later still your planet turned to the EM-band of communications. This included radio, television, radar, and a vast number of wireless devices. Your airwaves were crammed full of radio emissions leaking from your planet. Understand, these emission would barely be a carrier signal at 40 light years, and at 4000 light years would be a statistical anomaly on the EM band.
Later still you went digital and worried that people distant space civilization wouldn't hear you. Distant civilizations listen for EM band traffic. As stated, it's too hard.
If you continue to progress you will discover Distant Quantum Stimulation (the first step to efficient energy transmission). This *will* emit very strong EM-band emissions to space and is usually the sign of an emerging intelligence.
Later still will come high-energy Quantum Split-pair Sympathetic Signaling Systems (QS^4). This will come about to overcome the vast light-speed time delay in signaling between distant planetary bodies. However in using this there is sympathetic movement by unrelated quantum-bits in other solar systems. Some of those have intelligent life that will take notice.
Much much later, when you really start needing energy you will turn to Solar Photosphere Mining. This can either be "light" mining with light lenses and hot-cold energy channels (mega-batteries), or "heavy" mining like what you Earthlings call Dyson Spheres. Needless to say this significantly alters your star's appearance and can easily be seen at a distance.
In the far distant future you may discover the uses of dark matter - after all it *does* make up the vast majority of the universe. You really should know that there are ways that it can be used. It has vast potential. However any alternation and modification of the great web that is dark matter can be detected far far away. Civilization far and wide will be able to detect such an occurrence and celebrate with the graduating stellar system it's true achievement.
From here vast vistas await. There is no point in detailing them because there will be no point in searching for intelligence beyond your planet. This is because in improving your technology you also improve your capabilities. As you use those techniques more and better means of seeing further and understanding more become available.
There is no use at the lamating of an obsolete technology. To do so is to lament the passing of coastal semaphore stations and bonfire posts to warn of impending raids by Viking longboats. Your planet does not spend much energy in trying to detect such now-questionable methods of communication. Similarly other galactic civilizations do not spend much time or energy scanning for EM-band radiation.
Silly humans with their Very Large Arrays...