Europe is all set to launch the Galileo satellites its answer to the US GPS and Russian GLONASS on Friday, 21st October. The launch was supposed to have taken place early today (i.e. on 20th October), but unforeseen situations forced the launch to be shifted the next day. The satellites, a joint venture between European Space Agency and Roscosmos, will be launched using the Russian Soyuz rockets, marking the first use of Soyuz to launch a non-Russian payload.
Self-Reliance is the Keyword
The Galileo system will free up the European nations from their reliance on American technology for a reliable tracking system. The US GPS is available to all, but it can be discontinued or restricted in times of war. If not completely barred, the precision of the service might also be curtailed by the US. The US GPS is ultimately controlled mainly by the US military, which holds very high priority in the policy making corridors of America. Galileo will free Europe of all such constraints.
Galileo will provide both high precision and low precision services. The low precision facilities will be open to all. The high-precision facilities will be used primarily by the military.
Features of Galileo
Navigational and Search-And-Rescue facilities
The Galileo system has some really great features, as compared to the US GPS and the Russian GLONASS. It will be an array of 30 satellites (27 active ones and 3 spares) all in an orbit about 23,000 km above the Earth’s surface. The navigational precision of Galileo is rumored to be better than the US GPS, though the exact numbers are not yet known. Galileo will also be able to do Search-And-Rescue (SAR) operations. Users can send distress calls along with their positions via the Galileo system to emergency agencies. Galileo has the additional facility of user feedback it will tell the user whether the rescue team has been deployed or not and what their location might be.
Time measurement facility
Galileo will fly up with four high precision atomic clocks of two types. The first type is a hydrogen based maser clock, which is accurate to 0.45 ns in 12 hours (i.e. it slows down by 0.45 nanoseconds in 12 hours!!). the clock uses the super-stable 1.4 GHz hydrogen atom transition line to measure time. The second type of clocks – Rubidium clocks – serves as back-up. The Rubidium clock is accurate to within 1.8 ns over 12 hours. Ultra-precise time measurement is one of the fundamental necessities of a proper positional and navigational system.
Friction with Big Brother: Did the US plan to shoot Galileo down?
The US apparently planned to even shoot the Galileo satellites using missiles, since it feared that the facility might be used for military purposes against it. Tempers have cooled down and, with ESA declaring that the satellites won’t be used for spying, the US has no problem with the launch of the Galileo systems.
Named after the first real scientist, Galileo Galilee, the satellites aim to do what the great man always wanted to teach self-reliance in the matter of knowledge and thought.
All images courtesy the ESA image gallery: http://www.esa.int/esa-mmg/mmg.pl?type=I&mission=Galileo