About the Allen Telescope Array

To All The SETI Stars – Thank You! You’ve been wonderfully supportive of our efforts to bring the Allen Telescope Array out of hibernation and relaunch our search of the Kepler worlds. On the 1st of September, as soon as we had a viable new partnership cemented to operate the ATA, our Center for SETI Reseach team started reoccupying the Hat Creek site. We hauled back all the gear that we had removed for safe-keeping during hibernation and began to reinstall it and test it out. This sounds simple enough, but it really was a pretty complex undertaking to get everything reconnected and working well again. And of course, there were also the low-tech surprises like the gigantic weeds that took over the site, and a frozen line on the HVAC compressor. On December 5th, we started observing again, but this time with a difference. Instead of choosing observing target candidates from our list of HabCat stars, or scanning the region near the center of the Milky Way galaxy, we began choosing the planetary systems represented by the 2321 exoplanetary candidates announced by the Kepler Mission on that same day. Within the next 3 years we should be able to explore all the Kepler candidate exoplanets, and the exoplanets discovered with groundbased techniques across the terrestrial microwave window from 1 to 10 GHz. We hope that you will follow the search on the SETI Stars site, and invite your friends to join us as well. This site will provide daily updates and statistics on the signal detection processes, as well as opportunities to speculate on what will happen next. And of course we greatly appreciate your continued financial support for our research team. Our SETI search is enabled only via your generosity

Allen Telescope Array

The ATA is part of a new trend in radio astronomy. Rather than a single large dish, it is an array of a large number of small dishes (LNSD). Large single dishes are expensive, one-of-a kind development projects with every aspect optimized to get the best result for that investment. Once it is built, improving its performance is difficult and expensive.

The ATA represents an entirely different approach. The dish components are manufactured through a process developed for the television industry. Thus, the dishes are relatively inexpensive. We can increase the sensitivity of the array by simply adding more dishes. The receivers and cryogenic refrigerators were developed for radio communication and cell phones. We use programmable chips and software for signal processing. This allows us to increase the capability of the ATA as new computer technology becomes available.

Kepler Mission

The Kepler Mission was developed over several decades as a way of answering the question: How frequent are other Earths in our galaxy? In particular, what is the frequency of Earth-size planets in the HZ of solar-like stars?

SETI focuses on the planetary systems found by the Kepler Mission and ground based searches as research to suggests the possibility of habitable planets there.

Kepler Candidates

The Kepler mission has a list of “candidate exoplanets.” Kepler has made thousands of likely exoplanet discoveries, but in order for each planet to be considered “confirmed”, its existence has to be verified using other instruments, a process that takes time.

As the SETI and Kepler team as well as other researchers across the world sift through the Kepler mission’s immense collection of data, it’s possible that some candidates will prove to be “false positives” – findings that appear to be exoplanets at first, but later turn out to be the result of other cosmic phenomena.

However, it’s very likely that the vast majority of the Kepler exoplanet candidates, especially those in multi-planet systems, are real exoplanets.


In April 2011 the Institute was forced to stop searching with its SonATA system because there were no funds to operate the ATA. A couple of SETI enthusiasts wanted to do what they could to help using their web and social network knowledge. The SETIstars movement was started. A specific challenge to raise the funds needed to bring the telescopes and SonATA system out of hibernation (once a new operating partner had been found for the ATA) was launched on setistar. That initial challenge was quickly met and provided necessary funds for the people and logistics necessary to get back on the air on December 5. The successful campaign demonstrated just how dedicated SETIstars are and how willing they are to be participants in a community to share thoughts and become engaged in search. SETIstars will now provide a platform for that participation and a means to support the SETI science team as the search continues.