What data was seen on December 7, when the spacecraft arrived at Jupiter?
Unlike the Voyager flybys of Jupiter, Saturn, Uranus and Neptune, Galileo didn’t send back pictures “live” on arrival day. The atmospheric probe’s data, and fields and particles observations of Io’s plasma torus, were stored on board the spacecraft for later transmission to Earth. So, what did the “real time” data show? For starters, we received confirmation that the orbiter was “in lock” with the probe, and that the probe relay proceeded as planned. Although we didn’t see the actual data, this was still a tremendous reassurance to the project and to the probe’s scientists — keep in mind that there had been no communication with the probe since its release in July! We also saw engineering and tracking data that showed us that Galileo’s 400-Newton main engine was performing as scheduled, sending the craft into orbit around Jupiter. You can be sure that this also brought forth major sighs of relief from the flight team, since the orbiter’s mission was completely dependent on orbiting Ju
