Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

European gravity mission to benefit from ion thruster precision

12.01.2007
Final testing of the ion thrusters that will enable a European space mission to measure and map the Earth's gravity field in far greater detail than ever previously achieved has been completed.

QinetiQ's T5 ion thrusters will provide high precision drag compensation for the European Space Agency (ESA) GOCE spacecraft, due for launch later this year. The data captured by GOCE will contribute significantly to our understanding of the Earth's structure, climate and the impacts of climate change.

QinetiQ was awarded a £4.6 million contract by Astrium, ESA's prime contractor for the GOCE platform, in 2001 to provide the two Ion Thruster Assemblies (ITAs) for the spacecraft. By using QinetiQ's T5 ion thruster the spacecraft will be able to compensate for the drag experienced in orbit, thereby allowing highly accurate measurements of the Earth's gravity field.

Travelling at 8 kilometres per second and operating at an orbital altitude of 240 kilometres, the spacecraft will experience a small but significant disturbance in its motion from atmospheric drag. This disturbance is constantly changing so continuous and precise compensation is needed to allow the highly sensitive accelerometers on board to map the earth’s gravitational field. The extreme control precision provided by the T5 ion thrusters has been likened to compensating for a snow flake landing on the deck of a super tanker.

Alex Popescu, ESA's GOCE mission manager, said: "The data collected by GOCE will be vital for the next generation of geophysical research and will contribute significantly to furthering our understanding of the impact of ocean circulation on the Earth’s climate. Without the precision that is provided by the spacecraft's thrusters the mission would be impossible. Consequently, the final testing of the propulsion system is an important milestone."

Steve Morton, QinetiQ's GOCE project leader, welcomed the impending delivery of the thruster assemblies, saying: "QinetiQ's ion thrusters will play a key role in the success of GOCE as the thrust accuracy requirements of the mission demand a lot of the spacecraft's propulsion system. We have needed to push the boundaries of current knowledge and technology and are proud to be so centrally involved in this important mission."

In addition to the precision provided by the T5 thrusters, the ion engines are also exceptionally mass efficient, requiring only 40 kilogrammes of propellant for the entire 20 month duration of the mission. This is achieved by ejecting xenon gas propellant out of the thrusters at a velocity in excess of 40 thousand metres per second, which is at least 10 times faster than any other conventional rocket thruster employing volatile chemicals, such as those used on the Space Shuttle.

In addition to providing the T5 thrusters, QinetiQ has produced control software and algorithms for the GOCE propulsion system. QinetiQ is also supporting the testing of the complete propulsion sub-system, the Ion Propulsion Assembly (IPA), of which the ITA is a key component and for which Astrium has overall responsibility.

QinetiQ is currently working with partners to qualify its T6 thruster, an even more advanced electric propulsion system aimed at enabling deep space missions and capable of extending the operational life of the next generation of commercial communications satellites.

About GOCE

The GOCE (Gravity Field and Steady-State Ocean Circulation Explorer) mission is dedicated to measuring the Earth’s gravity field and modelling the planet's geoid, essentially a gravitational contour map, with extremely high accuracy and spatial resolution. It is the first Earth Explorer Core mission to be developed as part of ESA’s Living Planet Programme and is scheduled for launch in 2007.

A precise model of the Earth’s geoid is crucial for deriving accurate measurements of ocean circulation, sea-level change and terrestrial ice dynamics – all of which are affected by climate change. The geoid is also used as a reference surface from which to map all topographical features on the planet.

An improved knowledge of gravity anomalies will contribute to a better understanding of the Earth’s interior, such as the physics and dynamics associated with volcanism and earthquakes and also further our knowledge of land uplift due to post-glacial rebound.

Ben White | alfa
Further information:
http://www.QinetiQ.com

More articles from Physics and Astronomy:

nachricht Engineering team images tiny quasicrystals as they form
18.08.2017 | Cornell University

nachricht Astrophysicists explain the mysterious behavior of cosmic rays
18.08.2017 | Moscow Institute of Physics and Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>