Another opening, another show

The first phase of the Allen Telescope Array (ATA)--the new UC Berkeley/SETI Institute radio array under construction at Hat Creek--is now up and running. This new radio array exploits cheap 20-foot aluminum radio dishes to synthesize a large collecting area and wide field of view. The ATA is also a multitasker: It can can look at different parts of the sky at the same time (the telescopic equivalent of having eyes in the back of your head), maximizing available observing time.

The ATA can pull the same trick in the frequency domain, taking data anywhere between 0.5 and 11 Gigahertz on any dish at any time. If you were to compare that to how the human ear processes sound, it would be no great shakes--we can process sound waves spanning about ten octaves. But for a radio telescope, it's like suddenly being able to hear the whole orchestra when, before, you could only pick up the flute or the bass.

The ATA will also be a full-time SETI instrument. That's not to say that it won't be doing "traditional" radio astronomy, too: It can do both at the same time. So data will be piping through the SETI computers 24/7, stepping up the speed of targeted searches by 100x.

This first phase included forty-two dishes; the plan is to bring that number up to 350--when more money comes along. Half of the $50 million spent on the ATA to date came from Paul Allen's foundation. (For ideas on where they might come up with the rest, check out last week's column.)