October 9, 2001

Aliens Worse Than Needle In Haystack
By David Currie

There may be as many as 10,000 to 50,000 technologically advanced civilizations in the universe.  That estimate is based on the Drake equation, developed and modified over the past 40 years by SETI Chairman, Frank Drake. SETI (Search for Extra-Terrestrial Intelligence) encourages visitors to participate in an organized search for extra-terrestrial intelligence by downloading a program to analyze data collected by the massive array of radio-telescopes at Arecibo. The program downloads data from the SETI@home project at UC Berkeley http://setiathome.ssl.berkeley.edu into participants’ home computers. Data are analyzed, results uploaded back to SETI and a new set of data downloaded for analysis when the computer is not in active use. The project amplifies SETI’s computing power, allowing SETI to examine more information than they could otherwise handle. 

The goal of SETI is to intercept alien radio transmissions, but SETI, itself, doesn’t broadcast such signals into space because they would probably never be detected. Actually, a now famous message was transmitted into space in 1974 from the Arecibo Observatory. The message was broadcast for 3 minutes and consisted of 73 rows of 23 bits each. Encoded in the message was a description of our solar system, our location within the solar system, the compounds important for life on Earth, the structure of DNA, and a stick human form.  The message was transmitted towards star cluster M13 and should arrive there around Earth year 27,000. At the University of California, astronomers are also examining light pulses from space in the growing search for other technologically advanced worlds. 

Just because SETI believes that an Earth message would not be detected by aliens doesn’t mean they don’t believe that technological civilizations exist on other planets. And before you decide that no one takes SETI seriously, stop by and take a look at the list of SETI’s corporate sponsors. We asked retired physicist/ astronomer Tom Chester, still associated with the 2MASS project, to help us interpret some of the numbers at the SETI website. After Tom helped us interpret some of the numbers describing the size of the galaxy and the size of the universe, we began to better understand some of SETI’s estimates. 

Based on information published by SETI experts, we learned that, if aliens exist, they are probably thousands of light years away from us and two-way communication would be all but impossible. If we pick up any alien signals, the signals have probably been traveling through space for thousands of years, meaning that the aliens at the source of the signal are thousands of years ahead of us technologically (the “Wow” signal was such a candidate detected by the Ohio State Radio Observatory in 1977). Travel between galaxies is complicated by the fact that as the universe expands, the galaxies are probably moving apart at speeds faster than we could ever travel. If aliens did arrive here, they would have exceeded the speed limit imposed by Einstein’s relativity (light speed), meaning they would be a whole lot smarter than us, because we don’t believe it’s possible to travel faster than light. 

Feel like joining the search for extra-terrestrial intelligence? Download SETI’s software at http://setiathome.ssl.berkeley.edu/download.html. Then stop by SETI.org and find out if someone is really hiding ALF in their garage, who is responsible for those crop circles, and if life on Earth originated from biological building blocks that arrived from space. Oh, and if you happen to get the heebie-jeebies tonight, thinking about someone (something) tinkering away with some pretty technologically advanced toys on a distant planet, why not take a trip back to 1947 and the most famous UFO crash in history … by visiting http://www.cowan70.freeserve.co.uk/alien_ufo/roswell.htm.

David Currie