The Galileo spacecraft and probe traveled as one for almost six years. In July 1995, the probe was
released to begin a solo flight into Jupiter.
Five months later, the probe sliced into Jupiter's atmosphere at one-hundred-six-thousand miles
per hour. It slowed, released its parachute, and dropped its heat shield. As the probe descended
through ninety-five miles of the top layers of the atmosphere, it collected fifty-eight minutes of data on
the local weather. The data were sent to the spacecraft overhead, then transmitted back to Earth.
It appeared that Jupiter's atmosphere is drier than we thought. Measurements from the probe
showed few clouds, and lightning only in the distance. It was only later that we discovered that the
probe had entered an area called a "hot spot."
Towards the end of the 58 minute descent, the probe measured winds of four-hundred-and-fifty miles
per hour - stronger than anything on Earth. The probe was finally melted and vaporized by the intense
heat of the atmosphere.
To get into orbit around Jupiter, the spacecraft had to use its main engine. An error could send
Galileo sailing past the planet. There was just one chance to get it right. After hours of anxious
waiting, mission controllers confirmed that the spacecraft was safely in orbit. Galileo was alive and
well and had begun its primary mission. The maneuver was precisely carried out, and Galileo entered
orbit around Jupiter.
The Probe Mission Events Diagram
Quick Facts about Probe Mission:
- Release Date: 7/13/95
- Penetration into Jupiter's Atmosphere: 12/7/95
- Entry Speed: 106,000 mph
- Probe Data Return: 59 min, 3.5 megabits
- Penetration depth: 200 km (124 mi)
Next: The Orbital Tour of Jupiter - Galileo's Prime Mission