Definition
Galileo is the European Union's global satellite navigation system, providing positioning, navigation, and timing services through a constellation of satellites in medium Earth orbit. It is one of several Global Navigation Satellite Systems (GNSS), alongside the United States' GPS, Russia's GLONASS, and China's BeiDou. Galileo signals can be used independently or in combination with other GNSS constellations by suitably equipped receivers to improve position accuracy, availability, and integrity.
Plain English
Galileo is Europe's version of GPS. It's a network of satellites that tells receivers on the ground exactly where they are. Aircraft equipped with the right receivers can use Galileo by itself or alongside GPS for better, more reliable position information.
Context Anchor
Seen in GPS and satellite navigation discussions, especially when a receiver can use signals from more than one satellite system.
Derivation
Named after Galileo Galilei, the 17th-century Italian astronomer whose work on celestial motion helped lay the foundations of modern navigation. The name signals that this is a European civil system rather than a military one.
Why Pilots Care
Supplies an independent navigation signal that increases redundancy and can improve positioning accuracy when used alongside GPS.
Intuition Check
Galileo here does not mean the scientist himself or one satellite. It means the European satellite navigation system named after him.
Example Sentence 1
The aircraft's new GNSS receiver uses both GPS and Galileo signals, giving it more satellites to work with at any moment.
Example Sentence 2
Preflight checks confirmed that the receiver was configured to use both GPS and Galileo constellations for improved coverage.