ESA GALILEO: Satellite Recovered and Transmittting Navigation Signals

ESA's Galileo satellites are placed in medium orbits, at 23 222 km altitude along three orbital planes so that a minimum of four satellites will be visible to user receivers at any point on Earth once the constellation is complete. 

Credit: ESA

ESA’s fifth Galileo satellite, one of two delivered into a wrong orbit by VS09 Soyuz-Fregat launcher in August, has transmitted its first navigation signal in space on Saturday 29 November 2014.

It has reached its new target orbit and its navigation payload has been successfully switched on.

A detailed test campaign is under way now the satellite has reached a more suitable orbit for navigation purposes.

Recovery

The fifth and sixth Galileo satellites, launched together on 22 August, ended up in an elongated orbit travelling up to 25 900 km above Earth and back down to 13 713 km.

A total of 11 manoeuvres were performed across 17 days, gradually nudging the fifth satellite upwards at the lowest point of its orbit.

As a result, it has risen more than 3500 km and its elliptical orbit has become more circular.

“The manoeuvres were all normal, with excellent performance both in terms of thrust and direction,” explained Daniel Navarro-Reyes, ESA Galileo mission analyst.

“The final orbit is as we targeted and is a tribute to the great professionalism of all the teams involved.”

The commands were issued from the Galileo Control Centre by Space Opal, the Galileo operator, at Oberpfaffenhofen in Germany, guided by calculations from a combined flight dynamics team of ESA’s Space Operations Centre, ESOC, in Darmstadt, Germany and France’s CNES space agency.

The commands were uploaded to the satellite via an extended network of ground stations, made up of Galileo stations and additional sites coordinated by France’s CNES space agency.

Satellite manufacturer OHB also provided expertise throughout the recovery, helping to adapt the flight procedures.

Until the manoeuvres started, the combined ESA–CNES team maintained the satellites pointing at the Sun using their gyroscopes and solar sensors. This kept the satellites steady in space but their navigation payloads could not be used reliably.

In the new orbit, the satellite’s radiation exposure has also been greatly reduced, ensuring reliable performance for the long term.

NEE-02 Krysaor: Ecuador satellite starts transmitting

A nanosatellite Ecuador launched began transmitting Saturday, and picked up a signal from another that had been lost, the Ecuadoran Civilian Space Agency said.

Krysaor "has started operating on schedule," the agency said, referring to the tiny traveler measuring just 10 by 10 centimeters (3.9 inches). It measures 75 centimeters when unfolded.

Weighing in at just 1.2 kilograms (2.65 pounds), the $160,000 orbiter was launched from Russia last year and is due to broadcast in near-real time for local educational uses.

EXA is the first space agency in the history of Ecuador, it has its own astronaut, the ASA/T Ronnie Nader, who is the Director of the Space Operations Division and is also the Honorary Chairman of the Directorate Board of EXA.

The website reports that his state of service is active, his position is of Mission Specialist and his function is Mission Commander.

Ecuador launched a similar satellite, Pegaso (Pegasus), in April.

It ceased to be heard from in September after hitting remains of a Russian launcher but authorities said they also had recovered the signal from Pegaso after Krysaor began transmitting.

"Who would ever have imagined that we could launch Ecuadoran satellites, however small they may be! We are going to continue with our space program," said an enthused President Rafael Correa, a leftist and economist by training.