By Cristina Deptula
This post was written by a guest author who attended our April PubScience event. To learn more about PubScience or how guest posts may be published, contact us at firstname.lastname@example.org.
I’m Cristina Deptula, a writer and community member who heard about Dr. Dan Werthimer’s talk over Facebook while searching for local Oakland events. I volunteered to take notes and write about what I heard for the hosts of the event, UC Berkeley’s The CLEAR Project, in hopes of encouraging others to come out to see these free public science talks, in a monthly series they call PubScience.
‘Hello? Anybody home? Who’s there?’
We’ve been asking this for quite awhile.
For decades, people have lent some of their computers’ processing power to the Search for Extraterrestrial Intelligence, or SETI, to help scientists process data from radio telescopes that could contain communication from alien life. Dr. Dan Werthimer, co-founder and chief scientist of Berkeley SETI, offered a ‘state of the search’ update Thursday, April 18th at Oakland’s Octopus Literary Salon.
Werthimer presented an overview of current scientific thought on the question. He discussed the Drake equation, a widely cited formula developed in 1961 estimating the
probable number of civilizations within the Milky Way capable of communicating with us. It’s based on multiple factors, including the estimated number of stars, how many of them have planets that could support life, and how long it may take for life to develop into a civilization. While the Drake equation is clearly a simplification, researchers find the model useful even today.
He also covered NASA’s Kepler mission, which aims to survey 150,000 stars within the Milky Way for Earth-sized ‘Goldilocks planets’ that have a temperature range that’s just right to sustain life as we know it. We’re also looking at Jupiter’s moon Europa which has an underground ocean and at Saturn’s moon Enceladus where water squirts out of geysers. Earth life is so highly dependent on water that we expect life elsewhere to also form in the presence of water, although species elsewhere may operate according to an entirely different kind of chemistry.
Various historical personages came up with different ways to signal to aliens that we intelligent humans had built a civilization here. Many of these are humorous when heard through modern eyes and, as Dr. Werthimer was an entertaining speaker, he mentioned and illustrated several of them: mathematician Carl Friedrich Gauss proposed building a structure in a farm field with the proportions of the Pythagorean Theorem, while Joseph Van Littron suggested that we create a circle of light from burning kerosene. Other proposals involving mirrors and light were also rejected, and ultimately, on the Pioneer spacecrafts, we went with sending out music samples and images of naked people.
Returning to highlight current efforts, he explained SETI’s SERENDIP project which scans data from the large telescope array in Arecibo, Puerto Rico – that other researchers are already recording to make their own, independent observations – in hopes of serendipitously discovering a radio signal from space. They look for relatively strong signals, or drifting signals that could indicate a civilization’s technology rather than the steadier, expected movement of a natural body.
The UC Berkeley SETI@home effort harnesses the power of laptops connected to the Internet to process this data and has developed and branched out into further citizen science projects involving ordinary people and their computers. If your computer finds strong evidence of alien communications, you can have your name included in the science literature surrounding the discovery! So far over eight million people have participated, contributing to the data analysis of our skies that would take hundreds of years to complete without public involvement. Luckily, Moore’s law, which attempts to estimate how much more powerful computers will become over time, indicates that we will be able to do even more as time passes.
While we have yet to discover alien life through SETI, the effort has expanded our knowledge and awareness of astronomy. The people who work with SETI@home have also ventured into other projects, such as developing a science curriculum for children and identifying many interesting exoplanets, including one which could be covered in graphite and diamond.
Also, we make some discoveries in science while pursuing other mysteries. For example, we identified pulsars, rotating neutron stars emitting regular bursts of light, because we first investigated them out of curiosity, thinking they might be signals from alien life.
So, it seems both fascinating and worthwhile to continue to call out ‘Anybody Home?’ to the universe, and to listen through our radio telescopes for any possible answer.