Friday, January 18, 2008

Comments Are Welcomed!

Just wanted to take a moment to emphasize that comments are most certainly welcomed. Comments that challenge, correct, or debate are as welcomed as those that add to, support, or pose additional questions. This blog is an discovery process and a brainstorming process for me, and, I hope, for others as well, and it is helped along by comments.

Thursday, January 17, 2008

SETI@home looking for more volunteers

SETI@home looking for more volunteers

– The longest-running search for radio signals from alien civilizations is getting a burst of new data from an upgraded Arecibo telescope, which means the SETI@home project needs more desktop computers to help crunch the data.

Since SETI@home launched eight years ago, the project based at the University of California, Berkeley's Space Sciences Laboratory has signed up more than 5 million interested volunteers and boasts the largest community of dedicated users of any Internet computing project: 170,000 devotees on 320,000 computers.

Yet, new and more sensitive receivers on the world's largest radio telescope in Arecibo, Puerto Rico, and better frequency coverage are generating 500 times more data for the project than before. The SETI@home software has been upgraded to deal with this new data as the search for extraterrestrial intelligence (SETI) enters a new era and offers a new opportunity for those who want to help find other civilizations in the universe.

"The next generation SETI@home is 500 times more powerful then anything anyone has done before," said project chief scientist Dan Werthimer. "That means we are 500 times more likely to find ET than with the original SETI@home."

According to project scientist Eric Korpela, the new data amounts to 300 gigabytes per day, or 100 terabytes (100,000 gigabytes) per year, about the amount of data stored in the U.S. Library of Congress. "That's why we need all the volunteers," he said. "Everyone has a chance to be part of the largest public participation science project in history."

The 1,000-foot diameter Arecibo dish, which fills a valley in Puerto Rico, is part of the National Astronomy and Ionosphere Center operated by Cornell University with funds from the National Science Foundation. Since 1992, Werthimer and his team have piggybacked on radio astronomy observations at Arecibo to record signals from space and analyze them for patterns that could indicate they were transmitted by an intelligent civilization.

When the team's incoming data overwhelmed its ability to analyze it, the scientists conceived a distributed computing project to harness many computers into one big supercomputer to do the analysis. Since SETI@home was launched, other distributed computing projects have arisen, from folding@home to predict the three-dimensional tangle of a protein to the newly-launched cosmology@home to model possible universes. Most are now on a platform called BOINC (Berkeley Open Infrastructure for Network Computing), which was developed by SETI@home's director David Anderson so that the various projects could share resources.

"There are now 42 projects on BOINC, and, until now, there has been enough computing power to go around," Werthimer said.

What triggered the new flow of data was the addition of seven new receivers at Arecibo, which now allow the telescope to record radio signals from seven regions of the sky simultaneously instead of just one. With greater sensitivity and the ability to detect the polarization of the radio signals, plus 40 times more frequency coverage, Arecibo is set to survey the sky for new radio sources.

These improvements also prime the telescope for an improved search for intelligent signals from space.

"The multiple receivers help us weed out interference better and make us less susceptible to thinking that things terrestrial are extraterrestrial,"
Werthimer said.

Werthimer noted that, despite the fact that UC Berkeley has been analyzing radio signals from space since 1978 on various telescopes, no telltale signals from an intelligent civilization have yet been found.

"Earthlings are just getting started looking at the frequencies in the sky; we're looking only at the cosmically brightest sources, hoping we are scanning the right radio channels," he said. "The good news is, we're entering an era when we will be able to scan billions of channels. Arecibo is now optimized for this kind of search, so if there are signals out there, we or our volunteers will find them."

SETI@home has been funded by various organizations over the years, including the Planetary Society and Sun Microsystems, and continues to be supported by individual donations from its volunteers.

Further information:

SETI@home Web site (<http://setiathome.berkeley.edu/>)

Reference:

Sanders, Robert. " SETI@home looking for more volunteers." Press Release. UC Berkley News. 2 January 2008. 17 January 2008. <http://www.berkeley.edu/news/media/releases/2008/01/02_setiahome.shtml>

Wednesday, January 16, 2008

Update

The post Drake Equation has been updated - the javascript error has been corrected again (blogger loves to insert break tags on you if you are not careful), and some additional information and commentary included.

Tuesday, January 15, 2008

Introduction to The Drake Equation

The Drake Equation

I really shouldn't go on without at least an introductory mention of the famous (and controversial) Drake Equation created by Dr. Frank Drake in 1960.

Dr. Drake's equation is a tool for estimating the number of intelligent advanced civilizations presently in the Milky Way galaxy that we would theoretically be able to communicate with.

The Drake Equation is

N=(R)(fp)(ne)(fl)(fi)(fc)(L)

where N is the number of civilizations we can communicate with at this time in the galaxy, and where:
  • R = average star formation rate (10/yr)
  • fp = percent of those with planetary systems (50%)
  • ne = average number of planets that can potentially support life per star with planetary systems(2)
  • fl = percent of the above planets where life actually begins - life started on Earth very quickly, water and the complex organic building blocks for life are common in the universe (100%)
  • fi = percent of habited planets where intelligent life evolves (1%)
  • fc = percent of intelligent life that develop communication technology capable of transmitting into space(1%)
  • L = lifetime of all such civilizations on a particular planet - civilizations may collapse and rise again, or nearly wipe themselves out and the survivors rebuild (10,000 years)
The values in the parentheses are Dr. Drake's estimations. Using Dr. Drake's original values we arrive at N=10. As new data rolls with increasing frequency, these values tend to change. For more discussion see below. 

Assumptions
  • Liquid water is required for life, 
  • type M stars are too cool, 
  • type O and B stars are too short lived, 
  • life will develop if given a chance, 
  • developing intelligence gives a survival edge, 
  • and technologically advanced civilizations do not consistently prematurely destroy themselves because of their technological advances (global atomic war, for instance).
R, fi, and ne Discussion

As mentioned above, as new data rolls with increasing frequency, these values tend to change. Presently, the value for R is thought to be 6 per year. And, as mentioned a few times before in other postings in this blog, we are increasingly discovering certain intelligent traits first thought to be reserved just for humans cropping up in other animals: birds that make and keep tools, ferrets purposefully lying, and dogs mapping language to mention just a few. This indicate that the first estimation for fi (a mere 1%) may be too low.

If, however, sentient, intelligent life is so rare that we are the only one in the galaxy, or even the universe, then the vale for fi may be infinitesimally small. But, if we are the average result of habitable planetary system, and if life is found to have once existed on Mars, and to exist on Europa, then the value for fi becomes 33% (and ne becomes 3). That life formed quickly on Earth, a wet rock orbiting an average star in a nondescript part of the galaxy, then maybe, just maybe, it can form in extrasolar systems as well.

Calculate N for Yourself

See the Drake Equation Calculator on the right. Type in your own values for the variables in the Drake Equation to calculate N.

Habitable Zones and Habitable "Hot Spots"

Personally, I believe the habitable zone estimates are a bit conservative. For instance, Jupiter's moon Europa, despite being outside of our solar system's Habitable Zone, may have liquid water beneath its icy surface, and many scientists feel that Europa could support life. Thus, Habitable Zones could actually be larger, or a system could have Habitable "Hot Spots" (which includes not only planets, but large moons as well) in addition to its Habitable Zone . Maybe even an occasional type M stars could have habitable planet (see Color of Life for some discussion about life in a M class star system).

In addition, the equation does not take into account life that is spread to other planets by advanced civilizations (whether unintentionally from exploration or purposefully from terraforming). And finally, life is constantly surprising us with its great diversity here on Earth - our definition of what is life may need to be expanded.

Additional Drake Equation Posts.


Reference:

Schilling, Govert and Alan. M. MacRobert. "The Chance of Finding Aliens." SETI: Searching for Life. Sky and Telescope Magazine. 15 January 2008. <http://www.skyandtelescope.com/resources/seti/3304541.html>


Image credit: © Lynette Cook

Sunday, January 13, 2008

Alien Technology - 1. Biology/Physiology - Part II


"Enclosure" © DigitalBlasphemy.com
An article I recently read about "stereo noses" of certain insects got me to thinking about how some technological advances/abilities may be rather common because of a common need for communication in space and the universal nature of space: while different beings may communicate on their planet in a number of very different ways - by light, sound, touch, or smell for instance - because of the near vacuum of space, communication is somewhat limited. One cannot communicate by touch, sound, or smell through the vacuum of space; however, one can communicate by light, or rather by the electromagnetic spectrum (radio waves, x-rays, light, and so forth). So no matter how a species communicates amongst its members on their home planet, they are rather restricted to how they can communicate in space.

Thus, many feel we may fairly confidently look to the electromagnetic spectrum as the most likely means for communicating with most alien species, it may not be the best way to search for indications of intelligent life on other worlds. Most assume that intelligent life will, at some point eventually, if they survive long enough, develop technology that will include some forms of electromagnetic communication / transmission of information which would either "leak" out into space and/or would purposefully used for space communications. These signals would eventually be detectable by sensitive radio telescopes (by those who believe that such intelligent life would use mostly the radio band) or by optical telescopes (for those believe some advance civilizations would use lasers to communicate, at least for communication in outer space).

However, not all species may use the electromagnetic spectrum to communicate with each other on their home planet, and thus not leak out any evidence of their presence or of their advanced civilization into space and, eventually, if we are fortunate enough, be detected here on Earth by our telescopes.

Take, for an extreme example to make my point, a water world where the intelligent species has developed wholly as an underwater organism. Smell, light, and radio waves are not the most effective or efficient means of communication in water, due to the properties of water. But sound is a different matter - sound is a very effective means, which is why whales and dolphins, among others, are able to communicate over long distances (sometimes thousands of miles) via sound alone. Using electricity would be difficult, and so development in that area could be very slow.

As mentioned in a previous post, such a species may also be slow to leave the planet - a creature that needs to be immersed in water has a much heavier load to launch into space than a creature that needs to be immersed in air. Water is dense and very heavy, launching from under water and breaking free from the planet's gravity (especially if the gravity is even heavier than Earth's), carrying enough water to fully immerse one or more creatures, not to mention the mechanisms to not only oxygenate the water and remove waste air (and other wastes) which would be more complicated than those to care for a terrestrial creature, all would add up to a much much more difficult endeavor than it is to launch from the surface, in air, with air breathing terrestrial passengers.

However, it could be argued that such a species would tend, then, to rely wholly on robotic space probes (after they tackle the problem of creating such probes with electricity in a underwater environment from scratch - though one could suppose a heavy reliance on pneumatics, which while adding weight to the craft, would add far less than a water immersed passenger). In which case, they would need a means for communicating with the probes, and thus reveal themselves to other planets.

Although, let us pick, for a another extreme example, an intelligent species that deaf or nearly deaf with rudimentary vision and which communicates mainly by smell and touch. Such a species would not feel the need to develop TV or radio, though they may develop something akin to the teletype where they can, by touch, feel what is being transmitted. Such a device could easily be updated where the information is transmitted through the air via radio waves, which get converted by a braille type mechanism or even a pulsating mechanism which while producing sound as a by-product, it is the variations in the vibrations that can be felt by sensitive appendages which is how the message is deciphered. Thus, such a species would use a means of communicating over distances that would leak out into outer space and which could be eventually detected by radio telescopes on, or orbiting around the Earth.

Finally, someone once mentioned, in a discussion about the Drake Equation, that some species may be paranoid about broadcasting, even inadvertently, their presence to the universe and may restrict/shield and otherwise block signals from leaving their planet - there may be more advanced civilizations out there that we can not detect by our SETI or OSETI telescopes.

Such beings may be paranoid because their physiology causes them to be especially xenophobic, or because of their theology makes them so, or because their ruler is. Or it may be because of a negative experience they had with another alien species. Or it just may be they logically thought about it and saw how violent their own people can be toward each other over differences and how more technologically advanced civilizations tend to easily conquer less advanced civilizations and figure they should play it safe (there are those here on Earth that present this very argument against our having SETI programs which purposefully try to make contact with other worlds).

We've had many examples on Earth of cultures closing their borders to avoid contact from other countries because of the paranoia of the leaders - mostly to limit the influence of "subversive" ideas from other cultures that may cause the people to reject the leader, or the paranoia of a people in reaction to a negative experience with outsiders. And so it could also happen with at least some other alien worlds.

References:

"Optical SETI - OSETI."
Life in the Universe. 8 August 2001. 13 January 2008. <http://www.lifeinuniverse.org/noflash/OpticalSETI-07-01-03.html>

Rockefeller University. "Two 'Noses' Are Necessary For Flies To Navigate Well." ScienceDaily. 29 December 2007. 13 January 2008. http://www.sciencedaily.com/releases/2007/12/071226230117.htm>

Saturday, January 12, 2008

Alien Technology - 1. Biology/Physiology


"Enclosure" © DigitalBlasphemy.com
One important area of research for engineers is the area of human factors science or design -understanding and applying the properties of human capability to the design of technology (a somewhat oversimplified definition). The capabilities of the human being has to be taken into account. Some are obvious factors (when you are not speculating about non-human species) are such things as: humans are bipedal, have five fingers, and their knees bend inward not outward like some birds, to name but a few. There are many human factors that influence technology including, but by no means limited to, from how something is physically designed, to safety mechanisms that need to be installed, to what kind of assistance the human operator needs to operate the technology.

What does this mean for aliens? What it means is that what works for a human may not be the best solution or the solution chosen by an alien. An avian sentient species would need greatly different technology for sitting and control mechanisms (I wonder if a sentient creature that is used to flying, would look to fly beyond the atmosphere sooner than a terrestrial or especially an aquatic sentient species?). A creature that looks more like an octopus than a human would need different seating and control mechanisms as well. Having more fingers, lacking any fingers, having a tail, having more than two eyes, hearing different frequencies, not being able to hear at all, and any number of other physiological differences will affect what the technology will look like, how the species would communicate, and thus affect how we (humans) can find and communicate with an alien race.

And it is possible that there could be some intelligent species that cannot use technology (at least as we commonly define or have commonly come to think of as technology) or which may not have a pressing need for it, or are much slower in developing it because of their physiological limitations. Say, for an extreme example, there are long lived creatures with very slow metabolisms that communicate through touch or biochemical means and who carve out structures within boulders or large masses of rock by secreting acid - such creatures could eventually develop a complex society that discovers complex mathematics, and which ponders the deep questions of "being" and "existence" and the meaning of life; but certain technological development could be very slow - at least the type of technological development that includes physically exploring space and the ability to communicate beyond their planet.

References:

Human Factors and Ergonomics Society. 12 January 2008. <http://www.hfes.org/>

Human Systems Integration Division at NASA Ames. 19 December 2007. 12 January 2008. <http://humansystems.arc.nasa.gov/>

Alien Technology - Preliminary Thoughts

image credit: DigitalBlasphemy.com
"The Core" (c) DigitalBlasphemy.com
In speculating upon alien realities, one inevitable topic is what would alien technology be like?

OK, so how can we speculate, predict? One aspect is easy - the laws of physics, including the nature of space-time, are universal (or, at the very least regional). We can make some predictions based on predictions we can make for our own technology (for instance, the development of materials that can hide objects from light and sound).

But after that, much of alien technology will be influenced by the alien's 1) biology/physiology, 2) sociology/culture, 3) theology, 4) physical environment (planetary as well as the space environment), and 5) any outside influence (from another alien culture).

And as we will see later, all of the above are somewhat interconnected - each influencing the other to some degree.