By Dr. Gerry Harp, an astrophysicist at the
SETI Institute.
Figure 1: A waterfall plot. This shows the signal as a function of frequency (increasing to the right) and time (increasing to the top). A slanted straight line is just the sort of thing we look for in SETI searches. In this case, it is from the Voyager spacecraft, 100 times further from the sun than is the earth.
You know that feeling where you have a great idea about doing SETI but you don't have a large radio telescope handy when you need it? If so, then we have something for you.
For the past two years, the SETI Institute has opened its doors to citizen scientists over all the world by open sourcing our own signal detection system software and a test program offering "raw" telescope data that anyone can analyze. These offerings have generated significant interest and we're happy to announce an expanded archive of more than 3TB of setiQuest data is now available to all SETI enthusiasts and hosted through a generous donation by Amazon Web Services.
The raw data archive is reorganized with better documentation so you can perform your own "observations" of signals arriving from outer space in the directions of various interesting stellar objects from quasars and blazars to pulsars, from satellites orbiting the earth to spacecraft. It also includes Kepler exoplanets, super-hot O-stars which may be good energy sources for giant astro-engineering projects, and astrophysical masers which might be used as natural amplifiers for a SETI beacon.
Figure 2: Spectrum of a methanol maser, produced with the tools described here.
What's it all for? As the setiQuest data project has grown up, scientists and volunteers associated with the SETI Institute have developed a set of open-source programs to allow flexible data analysis, with a goal of prototyping new algorithms for the discovery of SETI signals. As of today, we're offering these tools to you in an open source package, graciously hosted at GitHub. Bringing these programs to the public was generously supported by Google through the Google Summer of Code program with excellent contributions from our mentee, Aditya Bhatt, an outstanding computer science student approaching graduation in Gandhinagar, India.
Using the setiQuest Data and Algorithms tools, you can produce conventional waterfall plots (like Fig. 1) on your own computer and examine them for interesting signals. The spectrum of methanol masers in the W3OH molecular cloud shown in Fig. 2 was generated using setiQuest data and the Algorithms tools, and plotted using Excel. Each bump in the spectrum is essentially a giant natural laser in a molecular cloud (except that the l="light" produced by this cloud is in the m="microwave" frequency range). Using the same tools, you can look for time variations in this signal which might indicate a SETI beacon.
These days, the nuts and bolts of SETI lie in the computational domain. The offerings described here are aimed at individuals with some computer skill, including a basic knowledge of C or another programming language. We are looking for citizen scientist collaborators to work with us on improving the package features or porting the code to other platforms. We're also seeking volunteers to help us lower the bar for getting started with SETI analysis and to use these tools to support other SETI projects such as setiQuest Explorer. If you're interested in SETI, spectroscopy, digital signal processing or just think this looks cool, then we invite you to join the fun at setiQuest.
For more information, follow the links and check the setiQuest forum.