Technology

A Swiss amateur Astronomer, Stefano Sposetti has managed to image Giove-A in orbit on Sunday Evening 8 January 2006. He used his 40 cm (16 inch) telescope to image a trace of the satellite. It should be remembered that it is 23,000 km (over 14,000 miles) away, and that it is matt-black in colour making it very difficult to see.

For the keen eye, the trace can be seen in the image below, moving from the Top-Right of the image towards the middle using a ten-second exposure.

Please click to enlarge the image.

Yesterday, the payload clocks were tested. They lock to the required frequency and work correctly.

Today is the first switch-on of the RF transmission system of the payload, which will send the first Galileo navigation signals to the ground.

There will be more updates tomorrow.

Europe's plans for its own global satellite navigation system take a massive step forward on 28 December with the launch of the GIOVE-A satellite from the Baikonur Cosmodrome in Kazakhstan.

GIOVE-A, the Galileo In-Orbit Validation Element, is the first phase in the GALILEO project that aims to give Europe a rival network to the US-based GPS system.

Designed by Surrey Satellite Technology Limited (SSTL) in the UK, the GIOVE-A spacecraft will carry out a number of major GALILEO objectives - including securing relevant frequencies, validating key technologies such as rubidium clocks, characterising the orbital radiation environment and delivering signals broadcasting in parallel via twin transmission channels.

The most important items of the GIOVE-A payload are two rubidium atomic clocks and a navigation signal generator capable of transmitting codes and frequencies to be used by the 30 satellites that will eventually make up the GALILEO network.

These navigation frequencies are in the so-called Radio Navigation Satellite Service (RNSS) frequency allocations established by the International Telecommunications Union (ITU) at around 1.5 GHz and in the 1.1-12 GHz range. Under current ITU regulatory provisions, RNSS signals from the GALILEO system must be brought into use by mid-2006 or risk being lost to other users.

Meanwhile, understanding the orbital environment is crucial because of the high levels of radiation present at the satellite?s 24,000 km medium Earth orbit (MEO). Much of the available data on this is held by the US as its GPS satellites operate in a similar orbit. However, independent measurements are considered crucial so that European components such as electronics and solar arrays can be radiation hardened sufficiently to ensure the longest life possible for the GALILEO network of satellites.

GIOVE-A was designed and built by SSTL, the UK-based company which has set the global benchmark for development and timely production of innovative low cost small satellites. At 660 kg and measuring 7-metres from tip-to-tip of its deployable solar array panels, GIOVE-A is the largest mini-satellite designed and built by SSTL to date and is also the basis of the Company's small Geostationary communications satellite product.

In fact SSTL's solution has already led to a Euro 100 million reduction in the overall cost to the European Space Agency (ESA) of the GALILEO project. In addition, SSTL designed, built, tested and delivered the GIOVE-A satellite within 27 months from contract award and met the stringent programme schedule objectives set by the ESA.

Over the years, the Company has developed an enviable reputation for producing and delivering successful satellites. As well as reduced cost and rapid satellite build times, the Company's flight proven and robust hardware ensures reduced mission risk - as demonstrated by 25 satellites built and launched by SSTL over 25 years for international customers with both civil and military applications.

Source: SSTL Press Release

Stevenage based Analyticon have been working with SSTL for over 2 years on the GIOVE-A satellite and are currently running simulations to ensure a successful launch.

Analyticon was responsible for designing the attitude control system for the satellite which will ensure that the satellite is pointing the right way whilst it travels round its orbit. The company has also been designing the orbit control system and orbit geometry .

It is also responsible for the mission analysis, including the eventual 'graveyard' orbit which will be implemented when the satellite has come to the end of its lifetime.

Analyticon website

Please note, "attitude control" is an industry term. For more details visit the link below.

Learn about attitude control