Updates GOCE Mission News

[Notebook]

GOCE achieves drag-free perfection

http://www.esa.int/esaCP/SEMGUV0OWUF_index_0.html

Not only does this mean that GOCE will deliver clean gravity data but it also marks a significant step in satellite technology. GOCE is the first-ever mission to fly drag free in low-Earth orbit using an electric propulsion system. Other missions using advanced electric propulsion technology only have the system turned on for short periods of time. Once operational, GOCE's system will be constantly compensating for the variations in air drag as it orbits Earth.

N.

 

[Bj]

Hate to drag up an old thread but new info on GOCE;

http://news.bbc.co.uk/2/hi/science/nature/8408957.stm

 

[Urwumpe]

Still pretty low quality of the data...will take a few more orbits.

 

[Orbinaut Pete]

Space News: "Computer Glitch Deemed No Threat to GOCE Mission".

SpaceRef: "GOCE giving new insights into Earth's gravity".

 

[tblaxland]

Looking very nice now :thumbup:

 

[Orbinaut Pete]

BBC News: "Computer blow to Europe's GOCE gravity satellite".

 

[SiberianTiger]

Hope it gets better.

 

[Orbinaut Pete]

Space News: "Ground Controllers Ready GOCE for Data Transmission Fix".

---------- Post added 30th Aug 2010 at 04:41 PM ---------- Previous post was 29th Aug 2010 at 07:57 PM ----------

Spaceflight Now: "Europe's GOCE satellite set to receive software patches".

 

[N_Molson]

A good point : rcs is still under control, the ion thruster is working perfectly and there still is a lot of xenon fuel available.

 

[Orbinaut Pete]

GOCE gravity mission back in action.

ESA's GOCE gravity mission has recovered from a glitch that prevented the satellite from sending its flow of scientific data to the ground. News of the recovery comes earlier than expected, thanks to the fervent efforts of a team of experts.

The recovery follows a serious communications malfunction on 8 July, when the Gravity field and steady-state Ocean Circulation Explorer (GOCE) satellite suddenly failed to downlink scientific data to its receiving stations.

Extensive investigations by experts from ESA and industry revealed that the issue was almost certainly related to a communication link between the processor module and the telemetry modules of the main computer. These telemetry modules are situated between the processor board and the transmitters, forming a vital part of the onboard data handling and communications system.

Recovery from the situation came after software patches gained access to troubleshooting information via the slow trickle of data that was still reaching the GOCE ground stations. This new information allowed the team to develop an understanding of the state of all the onboard systems. As part of the action plan, the temperature of the floor hosting the computers was raised by some 7°C – resulting in restoration of normal communications.

Plans are in place should the communications system experience the same glitch in the future. Software patches are now being developed to allow the two onboard computers to work in unison.

Volker Liebig, Director of ESA's Earth Observation Programmes, said, "We are very glad that one of the most innovative missions of ESA is back on track. I would like to congratulate and thank the teams from ESA and especially industry".

"I often get questions from journalists as to whether ESA satellites are not over-designed, with their redundancies and long lifetimes. This case shows how important it is to have these margins in case of problems. Consequently, we can now deliver scientists the full scientific programme."

The issue is not the first hiccup that GOCE has experienced since its launch in March 2009. In February 2010, a chip problem in the main computer meant that operators had to switch over to the satellite's backup computer system. There is, however, at present no evidence of any relationship between the two problems that have affected GOCE.

Orbiting through the outer remnants of Earth's atmosphere to sense the strongest gravity signal possible, GOCE is the most advanced gravity mission to date, designed to map variations in Earth's gravity field with extreme detail and accuracy.

Since becoming operational in September 2009, GOCE has already delivered two-thirds of the gravity data expected from the mission. Consequently, scientists worldwide already have a huge and immensely valuable dataset that will redefine our understanding of Earth's gravity field.

Moreover, with GOCE having regained its full capacity, it is hoped to continue the mission far beyond the end of the designated lifetime in 2011 – the satellite operations have, so far, required much less fuel than expected.

Rune Floberghagen, ESA's GOCE Mission Manager, said, "On 6 September the main instrument, the gradiometer, which measures the spatial variations in the gravity field in extreme detail, has also been switched on and shown to be fully functional.

"With everything back in proper working order, the satellite is now being gently brought back down to its operational status and altitude. This should be achieved before the end of September."

Source.

 

[orb]

Spaceflight Now: ESA overcomes glitch on gravity-mapping satellite.

 

[Orbinaut Pete]

BBC News: "GOCE gravity satellite 'caught the cold'".

 

[Orbinaut Pete]

ESA: "GOCE fully operational again".

 

[Orbinaut Pete]

Space News: "European Gravity Probe Returned to Normal Orbit".

 

[orb]

BBC News: Goce gravity mission traces ocean circulation:

The great sweep of water around Planet Earth has been captured from space in greater detail than ever before.

New observations from Europe's Goce gravity mapping satellite have allowed scientists to plot ocean currents with unprecedented precision.

Understanding gravity is fundamental to being able to track the direction and speed of water across the globe.

{...}

The ocean currents disperse heat, nutrients and even pollutants around the globe​

 

[Notebook]

ESA’s GOCE satellite has reached its ambitious goal of mapping Earth's gravity with unprecedented precision. In two short years, the sophisticated satellite has collected the measurements needed to record the 'geoid' reference shape of our planet.

http://www.esa.int/esaCP/SEMQC9VTLKG_index_0.html

 

[SiberianTiger]

This map gives a hint on what helps enlightened yogi to levitate:

 

[N_Molson]

Yeah, and in Western Europe & Indonesia, we've got our feet firmly planted into the ground :lol:

 

[Notebook]

Live streaming from ESA conference:

http://www.esa.int/SPECIALS/GOCE/SEM43Y3UFLG_0.html

N.

 

[orb]

ESA Portal: Earth's gravity revealed in unprecedented detail:

31 March 2011
After just two years in orbit, ESA's GOCE satellite has gathered enough data to map Earth's gravity with unrivalled precision. Scientists now have access to the most accurate model of the 'geoid' ever produced to further our understanding of how Earth works.

{...}

BBC News: Gravity satellite yields 'Potato Earth' view

Click on image to enlarge​

ESA's GOCE mission has delivered the most accurate model of the 'geoid' ever produced, which will be used to further our understanding of how Earth works.​

A precise model of Earth's geoid is crucial for deriving accurate measurements of ocean circulation, sea-level change and terrestrial ice dynamics. The geoid is also used as a reference surface from which to map the topographical features on the planet. In addition, a better understanding of variations in the gravity field will lead to a deeper understanding of Earth's interior, such as the physics and dynamics associated with volcanic activity and earthquakes.​

Credits: ESA/HPF/DLR​