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The Journey to Jupiter Introduction Launch Cruise Arrival Orbital Tour Extended Tour Europa The Spacecraft Mission Operations

The Cruise - The Winding Road to Jupiter
Galileo didn't have enough fuel to fly directly to Jupiter, but the spacecraft could borrow some energy from Venus and Earth. Mission planners designed a flight path with the nickname "VEEGA" --- for Venus-Earth-Earth Gravity Assist. Galileo would slingshot once by Venus, and twice by Earth, gathering enough energy to get to distant Jupiter.

A view of the Moon in orbit about Earth
A view of the Moon in orbit about Earth

First stop --- Venus, where Galileo got the chance to try out the instruments and take pictures of the clouds around our sister planet. Flying by our home planet twice, we saw the Earth and Moon together, as someone from another world might view us.

After the first Earth flyby, Galileo's umbrella-shaped high-gain antenna did not open as planned. But there was still a way to get data, though more slowly. The Galileo team worked long and hard to reprogram the spacecraft's computer, and the engineers at the Deep Space Network upgraded their antennas as well. The result allowed scientists to capture almost all the information originally planned, using Galileo's smaller antenna.

Image of the asteroid Gaspra captured by Galileo
Image of the asteroid Gaspra captured by Galileo
On the first trip through the asteroid belt, Galileo captured close-up images of an asteroid named Gaspra. On its second cruise, Galileo discovered a miniature "moon" orbiting the asteroid Ida. This tiny body was named Dactyl.

In 1994, Galileo was perfectly positioned to watch the fragments of comet Shoemaker-Levy 9 crash into Jupiter. Earth-based telescopes had to wait to see the impact sites as they rotated into view.

Cruise Timeline

Venus Flyby
16,000 km distance

Earth-1 Flyby
960 km distance

Gaspra Flyby
1600 km distance

Earth-2 Flyby
305 km distance

Ida Flyby
2400 km distance
Discovery: Dactyl, first known moon of an asteroid

Comet S/L-9 Jupiter Impact
July 16-22, 1994

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