SETI - An alternate strategy

To date most SETI research has focused on the assumption that an advanced extra- terrestrial society will want to "communicate" with similar beings throughout the universe. But it is my belief that given the vast distances and time that communication via a "communications channel" even if it is one way, such as optical or radio frequency transmissions will be impractical.

The other challenge with “communication” between intelligent species is the “L” term in the Drake equation. L represents the length of time for which such civilizations release detectable signals into space. If L is relatively short then possibility of two separate intelligent civilizations being coincident in time to send and receive a signal is very small. So even though there may have been many intelligent civilizations we will probably never be aware of their existence.

Given these constraints I suggest instead that we look for extra terrestrial intelligence in a similar way we searched for signs of intelligence on earth prior to the modern age. We can not hope to communicate to prehistoric man, but we know that intelligent beings existed on earth thousands of years of ago through archaeological evidence such as cave paintings, pyramids, monuments, etc.

More recently societies have been burying time capsules for future generations to discover and hopefully marvel at our accomplishments and perspectives of the future. Indeed several spacecraft have included time capsules to be hopefully discovered by humans or extra terrestrial intelligent being s in the far future. Part of the Apollo 11 Lunar Module, still on the moon, includes a plaque showing the arrangement of the Earth's continents in 1969. The LAGEOS satellite (which will re-enter the atmosphere in 8.4 million years) contains a plaque showing the arrangement of the Earth's continents in the past, present, and future. Pioneer 10 and Pioneer 11 both contain plaques that give pictorial information about their time and place of origin. The two Voyager spacecraft each contain a golden record that contains pictures and sounds of Earth, along with symbolic directions for playing the record and data detailing the location of Earth.

The understandable challenge of physical time capsules is the probability of locating and/or discovering these time capsules by future generations or aliens. Given the vast distances of space it is highly improbable that these time capsules will ever be discovered by any kind of intelligent being.

So rather than deploying physical time capsules can we think of a way of deploying self replicating or self re-generating optical and RF signals that propagate forever and are easily discoverable and locatable?

Instead of searching for communications signal from an extra terrestrial intelligent civilization we should perhaps instead look for "archaeological" evidence of their existence with the most likely candidate being a easily discoverable self replicating electromagnetic time capsule.

Their a host of problems with current inter-stellar electromagnetic signaling such as attenuation, dispersion, group delay, etc etc. Given these limitations how could we hope to deploy a self replicating optical signal that will maintain its integrity over the vast distances and time of space?

In an interesting post ( by Paul Gilster of Centauri Dreams he calculates that "Sun-Alpha Cen direct radio bridge exploiting both the two gravitational lenses, this minimum transmitted power is incredibly… small! Actually it just equals less than 10-4 watts, i.e. one tenth of a milliwatt is enough to have perfect communication between the Sun and Alpha Cen.."

One should also note that a gravitational lens acts like a lens with a gradient refractive index which also collimate and reduce electromagnetic dispersion.

In theory one could propagate signals forever using this feature of gravitational lenses. In fact the famous Frank Drake of the eponymous Drake equation has proposed the creation of a galactic Internet using such principles. (

I challenge the reader of this missive to think of other ways of creating self replicating optical/rf time capsules. If we can come up with a plausible mechanism for deploying self replicating optical/rf time capsules the next obvious step would be to see if we can detect any such phenomena in our local inter stellar region.

If you have any suggestions or comments, or think I am completely nuts please feel free to contact me at

Monday, January 24, 2011

Quantum Entanglement Could Stretch Across Time

In the weird world of quantum physics, two linked particles can share a single fate, even when they’re miles apart.

Now, two physicists have mathematically described how this spooky effect, called entanglement, could also bind particles across time.

Wednesday, July 28, 2010

Orbital Angular Momentum – Bo Thide and Jan Bergman (SETI Talks)

Link to SETI Archive: On the extraction of all information embedded in radio siganls: Implications for SETI: A new idea for utilizing all of the information in photons for communication involves a little-know electromagnetic property: the photon’s orbital angular momentum (POAM). The communication and computer industries are actively looking at the possibilities. We will discuss current research and the implications for SETI.

Tuesday, November 18, 2008

Want to leave a message for whatever comes next?

From Wikipedia, the free encyclopedia
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For the Cypriot company see KEO Ltd

KEO is a space time capsule which will be launched in 2010 or 2011[1] carrying messages from the citizens of present Earth to humanity 50,000 years from now, when it will reenter Earth's atmosphere.

The KEO project is supported by UNESCO (who voted it "Project of the 21st century"), Hutchison Whampoa and the European Space Agency, among other institutions. Its name is supposed to represent the three most frequently used sounds common to the most widely spoken languages today, [k], [e] and [o],[2] though this is in fact mistaken, as the most common sound is [a].[3]

* 1 Personal messages
* 2 Other contents
* 3 Technical aspects
* 4 Project history
* 5 Similar Projects
* 6 See also
* 7 Notes
* 8 References
* 9 External links

[edit] Personal messages

Every person is invited to write a message addressed to the future inhabitants—the deadline is December 31, 2009. Messages can be posted via the the project's website, or sent by postal mail. The organizers encourage everybody to gather messages from children, senior citizens and the illiterate so that every culture and demographic on Earth is represented. The satellite has enough capacity to carry a four-page message from each of the more than six billion inhabitants on the planet. Once the satellite is launched, the messages (with personal names removed) will be made freely available on the web.

[edit] Other contents

KEO will also carry a diamond that encases a drop of human blood chosen at random and samples of air, sea water and earth.[4] The DNA of the human genome will be engraved on one of the faces. The satellite will also carry an astronomical clock that shows the current rotation rates of several pulsars; photographs of people of all cultures; and "the contemporary Library of Alexandria", an encyclopaedic compendium of current human knowledge.

[edit] Technical aspects

The messages and library will be encoded in glass-made radiation-resistant DVDs. Symbolic instructions in several formats will show the future finders how to build a DVD reader.

The satellite itself is a hollow sphere 80 cm in diameter. The sphere is engraved with a map of Earth and surrounded by an aluminium layer, a thermal layer and several layers of titanium and other heavy materials intertwined with vacuum. The sphere is resistant to cosmic radiation, atmosphere re-entry, space junk impacts and so on. For its first few years in orbit, KEO will sport an artful pair of wings 10 meters across that will aid in its spotting from Earth. As the satellite enters the atmosphere, the thermal layer will produce an artificial aurora to give a signal of the satellite's re-entry. The passive satellite will not carry any communications or propulsion systems. It will be launched by an Ariane 5 rocket into an orbit 1,800 km high, an altitude that will bring it back to Earth in 500 centuries, the same amount of time that has elapsed since early humans started to draw in cavern walls.

The satellite has not been built and no contract has been tendered for its construction.

[edit] Project history

The KEO project was conceived in 1994 by French artist-scientist Jean-Marc Philippe, a pioneer of space art. Messages began to be collected, and an initial launch date was set for 2001. Technical feasibility demonstration and other various delays have moved the launch date to 2010 or 2011.

[edit] Similar Projects

Several previous spacecraft have included time capsules for humans (or aliens) in the far future. The Apollo 11 Lunar Module (now on the moon) includes a plaque showing the arrangement of the Earth's continents in 1969. The LAGEOS satellite (which will re-enter the atmosphere in 8.4 million years) contains a plaque showing the arrangement of the Earth's continents in the past, present, and future. Pioneer 10 and Pioneer 11 both contain plaques that give pictorial information about their time and place of origin. Most famously, the two Voyager spacecraft each contain a golden record that contains pictures and sounds of Earth, along with symbolic directions for playing the record and data detailing the location of Earth. The Pioneers and Voyagers have left the solar system for interstellar space.

[edit] See also

* Bracewell probe
* Crypt of Civilization
* Westinghouse Time Capsules

[edit] Notes

1. ^ Current launch date estimation
2. ^ Official FAQ page
3. ^ Ian Maddieson and Sandra Ferrari Disner, 1984, Patterns of Sounds. Cambridge University Press
4. ^ Edge Life Magazine, May 2003

[edit] References

* Bridges, Andrew (Jul. 31, 2000). KEO: The 50,000-Year Mission to Earth
* Stenger, Richard (Aug. 29, 2000). KEO time capsule could remain in orbit until 52001 AD
* (Sept. 5, 2000). Time Capsule to Orbit Earth for 50,000 Years
* The Hindu Business Line (Aug. 29, 2002). Hutch brings space-time capsule project to India The Hindu Business Line
* (Sept. 4, 2002). KEO, a time capsule in space!
* The Digital Skyline (August 2003). A Message to the Future The Digital Skyline
* Ashraf, Syed Firdaus (Oct. 15, 2003). Once upon a time, 50,000 years ago...
* EUROPA (May. 28, 2004). New satellite carries hopes and dreams of humanity EUROPA

[edit] External links

Monday, February 25, 2008

Special Constellations that Nature would never produce

[I think Jaron's idea is very similar to my own that we need to build "galactic" pyramids and other artificial structures in space. But rather than moving stars and planets I think this can be done more practically by creating spatial spectral patterns that clearly would be the mark of intelligence. Using gravitational lensing as Raman amplifiers and optical circulators could possibly keep a signal radiating forever-- BSA]

A proposal to create special constellations that nature
would never produce

by Jaron Lanier

This month I seriously propose that we begin the process
of repositioning the sun and other nearby stars in order to send signals to aliens, and that we begin the search for signs that aliens might have done the same for our benefit.

Full article here:

Tuesday, February 5, 2008

Orbital Angular Momentum for SETI signaling

I have always been fascinated by Orbital Angular Momentum for another applications including deep space communications. Here is a quick article on the subkect

Also excellent overview paper on OAM

Wednesday, January 16, 2008

Channels versus Platforms for communication

[Google has a web site on the best of their research videos. Lots of excellent material - but the one I particularly recommend is Van Jacobson's talk on the future of the Net. Anybody who is doing research on next generation Internet and/or native XML/URI routing, repositories and peer to peer architectures should be interested in this talk. His basic premise is that Netheads are in danger of being caught in the similar closed mindset of how networks should be designed much in the same way that Bellhead researchers were trapped by circuit switching modality. His argument was that the current Internet is ideally designed for conversations between devices, while what we need now is global pltaform the dissemination of information.

In terms of SETI this means that we have to stop thinking of "communicating" with ETs by looking for communication channels, but instead look for and"join" inter-galactic discussion boards - sort of an intergalactic Facebook--BSA]

Van Jacobson's talk: Today's research community congratulates itself for the success of the internet and passionately argues whether circuits or datagrams are the One True Way. Meanwhile the list of unsolved problems grows. Security, mobility, ubiquitous computing, wireless, autonomous sensors, content distribution, digital divide, third world infrastructure, etc., are all poorly served by what's available from either the research community or the marketplace. I'll use various strained analogies and contrived examples to argue that network research is moribund because the only thing it knows how to do is fill in the details of a conversation between two applications. Today as in the 60s problems go unsolved due to our tunnel vision and not because of their intrinsic difficulty. And now, like then, simply changing our point of view may make many hard things easy

Monday, January 14, 2008