Targeted Search: Project Phoenix

The second major way of looking is to target, a priori to pick out the directions where you think there is a high probability of having a signal. This is what Project Phoenix, the project that I direct, is about.

Project Phoenix is a systematic microwave search from the frequencies between 1.2 and 3 gigahertz. We target a thousand nearby stars; we look at the nearest 100 stars independent of their spectral type; and we look at all known exoplanetary systems. Then we select solar-type stars, preferentially those that are a few billion years old and that do not have any companions that might disrupt planetary orbits.

We are also following up on 11 events that the META search published a few years ago on the possibility that these might turn out to be extraterrestrial transmitters which were below the detection threshold. Interstellar stimulation have may amplified them briefly so that they could be seen by the META system, but then they faded away and were never seen again. So we are going back to look with much higher sensitivity at these targets and to look several times.

The name Phoenix alludes to the project as rising from the ashes of congressional termination. Unlike the movie Contact, we do not wear headphones. But we do actually plan for success and there is a real bottle ofchampagne in the observer’s icebox at Arecibo.

The signal processing that we do is based on full-custom digital signal processing gear. We cover 20 megahertz of dual polarization bandwidth. With 1 hertz resolution we have 56 million channels that we analyze every second. It is full-custom. It is a pain and we will never do it that way again.

We can package the equipment in a trailer so that we can take it to large telescopes around the world. It is the silicon intelligence of the system that does most of the work, although at first it takes a lot of people to get the system up and running. Then it takes fewer people as the system learns to do the job.

Eventually, you have a system that runs itself and runs the telescope. Of course, now that we have it all working, we are about to build a new system that has five times the bandwidth, has higher resolution, and should be coming on line with the telescope by the Fall of 2000.

There are some things that are unique about Project Phoenix. As a NASA program, when we first deployed to Arecibo Observatory in 1992, we learned a very important lesson: one telescope is not enough. In an RFI (radio frequency interference) environment, which is temporally varying, you cannot do an efficient search program with one telescope.

Contributed by: Dr. Jill Tarter and Jim Miller