Spacecraft Galileo's Greatest Challenge!

Spacecraft Galileo was launched with its big antenna all folded up, to keep it protected. Unfortunately, when the time came to open it up, it wouldn't open all the way! It was stuck!

Galileo's engineers tried
EVERYTHING
to open the big antenna...

First the engineers thought warming up the antenna would help. They had Galileo turn towards the sun, so its metal would expand. But still the antenna stayed stuck!

Then they thought if the antenna was colder, that would shrink the pins holding the antenna in. Galileo was asked to turn AWAY from the sun.

Then they tried to HAMMER the antenna open, by sending commands to Galileo to try again and again to open it...		... but as they commanded Galileo's antenna motor to turn on and off, over and over, the big antenna just wouldn't open all the way!

Scientists and engineers from all over the world, and even the general public, tried to think of another solution, but nothing worked!

Galileo needed to be able to talk to Earth once out at Jupiter, and its small antenna only sent a very weak signal.

There was only ONE solution:
Galileo's engineers HAD to make the small antenna work better!

Galileo's engineers and computer software experts got together and started working on some ideas: they thought they could create new programs and software to compress the data Galileo would send back. This way, all the pictures Galileo took and the other information Galileo gathered would travel faster to Earth, even with the small antenna!

	For months and months, Galileo's support teams rewrote just about all its software. Then, slowly and carefully, the flight team transmitted it all to Galileo, as the spacecraft flew millions of miles away! The new software helped Galileo's small antenna send its pictures and other data back faster than anyone thought possible.

Finally, the large antennas of the Deep Space Network, located at three balanced points around the world, in Goldstone (California), Canberra (Australia), and Madrid (Spain), were asked to work together and with nearby antennas, to get all they could of the weak signal from Galileo's small antenna.

With the new software, the large arrays of antennas working together, and using the on-board tape recorder to store data until it could get sent, Galileo was all set for taking lots of pictures and learning all sorts of things at Jupiter. The mission was going to be a success!