Reobservations Report No. 7: On Last Day at Arecibo, SETI@home Turns to Distant Planetary System

It's a long day at Arecibo today, where the SETI@home team is working hard to make up for lost time. After getting bumped off the telescope last week to make way for Solar flare observations, SETI@home Chief Scientist Dan Werthimer and his crew will spend 14 hours today observing the locations of SETI@home's most promising candidate signals, as well as a few other interesting locations. Observations began at 8am this morning, Atlantic Standard Time (UT -- 4) and went on until 4pm. After a short break they began again at 6pm and will continue till midnight.

"The telescope is working great," Werthimer said, when reached towards the end of the first observing session. "We're observing a new target every 5 minutes or so." In total, Werthimer estimated, "we targeted around 70 locations in this session, 60 of them being SETI@home candidates." The rest were promising SETI candidates from other searches, major galaxies, and stars known to possess planets. These last are from a list provided by leading extrasolar planet hunter Geoff Marcy of U.C. Berkeley.

At 9pm tonight Werthimer and his team will observe the most intriguing star on Marcy's list. "55 Cancri," the 55th brightest star in the constellation Cancer, is a Sun-like star known to be orbited by two gas giants similar to our Jupiter. While one of these planets is a "hot Jupiter" orbiting very close to its star, the other orbits at a distance almost exactly equal to that of Jupiter from the Sun.

This arrangement of the planets around 55 Cancri is more similar to our own Solar System than any other planetary system discovered so far. Between the two gas giants, scientists speculate, smaller rocky planets could potentially orbit the star at an Earth-like distance. If that is the case, than such planets might possibly possess life, and who knows - maybe even intelligent life.

All this makes SETI scientists particularly curious about 55 Cancri. Tonight, for the first time, they will get a chance to listen in to this intriguing star.

With 18 hours of observation behind them, the SETI@home team still hasn't found any clear sign of ET. The current evaluations, however, are based only rough analysis in real time. The final results from the observations will have to wait until all the recorded data is parsed out into work-units and sent out to personal computers around the world. Only after SETI@home users process the data on their machines and send it back to Berkeley, will the SETI@home crew have a real notion of the results of their quest.

Following tonight's session the SETI@home team will pack up and head home to Berkeley, California. Even if ET is not found this time around, they expect to be back in about two years with a new set of candidates.