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  • richardmitnick 10:33 am on November 23, 2017 Permalink | Reply
    Tags: , , , , , ESA, GomX-4A and GomX-4B,   

    From ESA: “ESA’s latest technology CubeSat cleared for launch site” 

    ESA Space For Europe Banner

    European Space Agency

    23 November 2017
    No writer credit

    1
    Testing CubeSat pair.

    GomX-4B, ESA’s latest and largest technology-testing CubeSat, will be launched from China early next year, together with the near-identical GomX-4A. The pair will test intersatellite communication links and propulsion while orbiting up to 4500 km apart.

    The cereal box-sized GomX-4B has been passed as ready to travel along with its twin from manufacturer GomSpace in Denmark in early December to begin launch preparations in China.

    “GomX-4B is scheduled to be launched on a Chinese Long March rocket on 1 February, along with GomX-4A, owned by the Danish Ministry of Defence,” says Roger Walker, heading ESA’s Technology CubeSat initiative.

    The majority of tests were made at GomSpace and other facilities in Denmark, apart from thermal–vacuum testing – ensuring that the CubeSats can withstand the hard vacuum and temperature extremes of low orbit – which took place at ESA’s technical centre in the Netherlands.

    2
    GomX-4B with GomX-4A
    Released 13/10/2016
    Copyright GomSpace
    ESA has signed a contract for its biggest small nanosatellite yet: GomX-4B will be a ‘6-unit’ CubeSat, intended to demonstrate miniaturised technologies, preparing the way for future operational nanosatellite constellations.
    GomX-4B is double the size of ESA’s first technology CubeSat, GomX-3, which was released from the International Space Station last year.
    The contract with Danish CubeSat specialist GomSpace is supported through the In-Orbit Demonstration element of ESA’s General Support Technology Programme, focused on readying new products for space and the marketplace.
    Aiming for flight in late 2017, GomX-4B will be launched and flown together with GomX-4A, designed by GomSpace for the Danish Ministry of Defence under a separate contract.
    The two CubeSats will stay linked through a new version of the software-defined radio system demonstrated on GomX-3, while their relative positions along their shared orbit is controlled up to a maximum 4500 km.
    Such intersatellite links will allow future CubeSat constellations to relay data quickly to users on the ground. The same radio system will also be used for rapid payload data downloads to Earth.
    Nanospace in Sweden are contributing the highly miniaturised cold-gas thrusters for controlling the orbit, allowing future CubeSat-based constellations to be deployed quickly after launch.
    Additional technology payloads include a compact hyperspectral imager called HyperScout, developed by Cosine Research in the Netherlands; a miniaturised startracker from Innovative Solutions In Space, also in the Netherlands; an inhouse ESA experiment to test components for radiation hardness; and an ADS-B antenna for aircraft tracking, developed from the GomSpace system tested on GomX-3.

    CubeSats are nanosatellites based on standardised 10×10 cm units. GomX-4B is a ‘6-unit’ CubeSat, double the size of its predecessor GomX-3, which was released from the International Space Station in 2015.

    Roger adds, “The two CubeSats will test intersatellite link technology, routing data from one satellite to the other, then down to the ground station. Part of the ground testing ensured they could indeed talk to each other and the actual ground station on an end-to-end basis.”

    Once released from the rocket, the CubeSats will first orient themselves to align their antennas. Then GomX-4B will gradually fly away from its counterpart, pausing at around 100 km intervals with their intersatellite links activated to see how well they work.

    5
    GomX-4B
    Released 23/11/2017
    Copyright ESA/GomSpace
    ESA’s GomX-4B CubeSat will test intersatellite links and propulsive orbit control techniques for future constellation operations with twin GomX-4A, which is owned by the Danish Ministry of Defence under a separate contract.
    Both ‘6-unit’ CubeSats are being built and tested by Danish nanosatellite specialist GomSpace.
    A video shows a simulation of GomX-4B’s ‘launch and early operations phase’.
    This is the crucial stage when the nanosatellite is released from its launcher and initially tumbles through space – reproduced by hand here – before deploying its antennas to link up with controllers back on Earth.
    See GomX-4B’s vibration test – simulating the violent shaking of its rocket launch – here.

    Their separation will be controlled by new cold-gas propulsion on GomX-4B contributed by Sweden’s NanoSpace company, using highly miniaturised thrusters.

    They will maintain their links through flat, patch antennas and software-controlled radios at a maximum distance of some 4500 km – a limit being set by the operating concept of a minimum of 10 satellites equally spaced around the same orbital plane to form a future constellation.

    “As well as operating together, the two also have separate payloads,” says Roger. “GomX-4B is the first CubeSat to fly our new HyperScout hyperspectral imager, developed by cosine Research in the Netherlands through ESA’s General Support Technology Programme.

    “Hyperscout images Earth in 45 different spectral bands, gathering a wealth of environmental data – so much so, in fact, that the camera must perform its own processing to drastically reduce the amount needing to be sent back to the ground.”

    GomX-4B also carries a new small startracker for precise attitude determination developed by Innovative Solutions in Space in the Netherlands, an ESA test payload checking components’ susceptibility to space radiation, and a dedicated radio receiver to detect signals from worldwide air traffic.

    5
    Magnetic cleaning
    Released 23/11/2017
    Copyright ESA/GomSpace
    Technology CubeSat GomX-4B undergoing ‘degaussing’ – reducing the magnetic fields of its component parts by applying an opposite magnetic field to it – at ESA’s Mobile Coil Facility at its technical centre in the Netherlands in June 2017. Such a magnetic cleaning procedure is needed to optimise the performance of the ‘magnetotorquers’ the nanosatellite will use for attitude control, with electromagnets reacting to Earth’s magnetic field.

    “Now the testing has been concluded, our main job is to keep the satellites’ batteries topped off, ahead of their transport to China,” concludes Roger. “Once they arrive, they will be checked and the propellant tanks filled.”

    The pair is flying as secondary payloads with China’s Seismo-Electromagnetic Satellite, CSES-1, designed to detect precursor signals of earthquakes in Earth’s ionosphere, an electrically active outer layer of the atmosphere.

    See the full article here .

    Please help promote STEM in your local schools.

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    Stem Education Coalition

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 8:38 am on November 23, 2017 Permalink | Reply
    Tags: , , , ESA, Laid the foundations for European and world cooperation in meteorology that continues today,   

    From ESA: “Forty years of Meteosat” 

    ESA Space For Europe Banner

    European Space Agency

    1
    ESA Meteosat Second Generation

    22 November 2017
    No writer credit

    ESA’s first Earth observation satellite was launched on 23 November 1977. When the first Meteosat satellite took its place in the sky, it completed coverage of the whole globe from geostationary orbit and laid the foundations for European and world cooperation in meteorology that continues today.

    2
    Geostationary orbits of 36,000km from the Earth’s equator are best known for the many satellites used for various forms of telecommunication, including television. Signals from these satellites can be sent all the way round the world. Telecommunication needs to “see” their satellite all time and hence it must remain stationary in the same positions relative to the Earth’s surface.

    3
    A stationary satellite provides the advantage for remote sensing that it always views the Earth from the same perspective, which means that it can record the same image at brief intervals. This arrangement is particularly useful for observations of weather conditions. One disadvantage of geostationary orbits is the great distance to the Earth, which reduces the achievable spatial resolution.

    There are a number of weather satellites evenly distributed in geostationary orbit all around the world to provide a global view.

    Weather – and particularly extreme weather – affects everything we do. Being able to see the whole disc of Earth allows forecasters to see developing weather systems, as well as working out wind speed and direction based on cloud movements. Atlantic hurricanes appear on Meteosat images long before they interact with land, and data from space help to predict their tracks.

    Before weather satellites, forecasters relied on surface observations from land, ships and buoys, along with some information about the atmosphere provided by balloon-borne radiosondes, kites and aircraft. Satellites provided a vast new array of information that, coupled with new computer models, helped to make forecasts more reliable for longer periods.

    Meteosat was an important milestone in European cooperation in space. Individual countries had pioneered monitoring of the ionosphere from space and the European Space Conferences of the 1960s agreed in principle that there should be a European weather satellite, but it was not until Meteosat that the potential for meteorological satellites began to be fulfilled.

    4
    Meteosat-1 first image

    Meteosat was initiated as a French project, with involvement both from CNES and the French meteorological service. At the same time, the European Space Research Organisation (ESRO, a forerunner of ESA) was considering possibilities for polar-orbiting and geostationary satellites. ESRO decided on a geostationary satellite, which would clearly be a duplication of the French effort.

    Over a long period of fact-finding and negotiation, the foundations were laid for the Meteosat project to evolve from a French one to a European one. Rather than uproot the whole operation from France, it was decided to establish an ESA office in Toulouse, from where Meteosat could be developed and guided.

    Meteosat-1 lifted off at 13:35 GMT on 23 November 1977 from Cape Canaveral in Florida. It reached its operational orbit on 7 December 1977, and its first image was sent back on 9 December. It was the first satellite in geostationary orbit to have a water vapour channel to track the motion of moisture in the air.

    The new satellite required great improvements in ESA’s computing power – both for telemetry and for image data processing. From its position over the Greenwich meridian, Meteosat-1 could scan Earth’s full disc every 30 minutes, with the data being provided in near-real time to users.

    5
    Meteosat, the first-generation satellite

    Since the launch of the first Meteosat, 40 years of imagery and derived meteorological data from it and its successors have helped to significantly improve weather forecasting. There are 35 years’ worth of Meteosat imagery available online and the satellite’s record of imaging from space constitutes an important body of evidence in climate science.

    Although the early meteorological satellites were not envisaged as tools for measuring climate change, images of changes in land cover or polar ice and data on sea-surface temperature have become very useful for climate research and modelling.

    There was a gap of almost a decade between the launch of Meteosat-1 and the official founding of Eumetsat, the European organisation created to exploit satellite data for weather and climate research with the global community. Today, with clear operational responsibilities and funding, Eumetsat has become a global player in satellite meteorology. With 30 member states, Eumetsat continues to develop new satellite programmes in cooperation with ESA.

    The Meteosat programme always has one satellite in the operational position at 0º longitude. Meteosat Second Generation kept the drum-shaped design of the original but is two and a half times larger and offers improved resolution, 12 spectral channels as opposed to three on the original system, and faster scanning.

    Looking to the future, Meteosat Third Generation is in development, with new capabilities such as lightning detection, and will guarantee continued European monitoring of the atmosphere from space into the 2030s.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 9:56 am on November 16, 2017 Permalink | Reply
    Tags: Earth Explorer 9, , ESA, FORUM, SKIM   

    From ESA: “Two new Earth Explorer concepts to understand our rapidly changing world” 

    ESA Space For Europe Banner

    European Space Agency

    15 November 2017

    1
    A new era for science and society
    Released 17/11/2015
    Copyright ESA
    Earth observing satellites play a fundamental role in understanding our planet and how humankind is affecting Earth’s delicate balance. Using cutting-edge technology, Earth Explorer missions reveal new insights into how the oceans, cryosphere, atmosphere, land and Earth’s interior work as a system. While science continues to reap the benefits of these missions, we are now in a new era where Earth observation is benefiting society at large.

    ESA has chosen two concepts, FORUM and SKIM, to be developed further and compete to be the ninth Earth Explorer mission.

    Thanks to new technical developments, the Far-infrared Outgoing Radiation Understanding and Monitoring (FORUM) candidate would measure radiation emitted from Earth across the entire far-infrared part of the electromagnetic spectrum. Significantly, it measures in the 15–100 micron range, which has never been done from space before.

    These observations are important because Earth emits infrared radiation to space, which is affected by water vapour and cirrus clouds, which, in turn, play key roles in Earth’s temperature.

    FORUM’s benchmark measurements would improve our understanding of the greenhouse effect and, importantly, contribute to the accuracy of climate change assessments that form the basis for policy decisions.

    2
    FORUM far-infrared
    Released 15/11/2017
    Copyright INO–CNR
    The candidate Earth Explorer FORUM mission aims to measure radiation emitted from Earth across the entire far-infrared range. This is important because processes associated with water vapour and cirrus clouds, which play a key role in the greenhouse effect, influence the way Earth emits infrared radiation to space.

    The Sea-surface Kinematics Multiscale monitoring (SKIM) candidate would carry a novel wide-swath scanning multibeam radar altimeter to measure ocean-surface currents. Uniquely, it uses a Doppler technique, which offers more direct measurements than conventional satellite altimeters.

    These new measurements would improve our understanding of vertical and horizontal ocean–surface dynamics over the global ocean every few days. This would lead to better knowledge of how the ocean and atmosphere interact – for example, how atmospheric carbon dioxide is drawn down into the ocean.

    SKIM would have particular relevance for understanding the rapidly changing Arctic Ocean, and for observing equatorial regions where conventional satellite altimeters are unable to provide useful measurements of currents.

    3
    Simulating SKIM
    Released 15/11/2017
    Copyright CLS/CNES–C. Ubelmann
    Simulated high-resolution ocean-surface currents as expected from the candidate Earth Explorer SKIM mission. The simulated data is over a modelled Gulf Stream ring.

    ESA’s Director of Earth Observation Programmes, Josef Aschbacher, said, “As part of our effort to realise cutting-edge missions, Earth Explorers are built to answer some of the most pressing scientific questions about our planet.

    “Out of the 13 concepts that we received following our call for proposals last year, the Earth Science Advisory Committee recommended that FORUM and SKIM enter a competitive feasibility phase.

    “With this recommendation now accepted, these two candidates will spend the next two years being studied thoroughly. In 2019, a User Consultation Meeting will be held, after which a decision will be taken by ESA’s Member States as to which of the two contenders will be implemented.

    “We foresee Earth Explorer 9 being launched in 2025.”

    See the full article here .

    Please help promote STEM in your local schools.

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    Stem Education Coalition

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 9:23 am on November 15, 2017 Permalink | Reply
    Tags: , , , , ESA, M-Argo Deep-space CubeSat   

    From ESA: “Deep-space CubeSat” 

    ESA Space For Europe Banner

    European Space Agency

    1
    M-Argo is designed as ESA’s first CubeSat to enter interplanetary space.
    Deep-space CubeSat
    Released 15/11/2017
    Copyright ©ESA-Jacky Huart

    Studied in the Concurrent Design Facility, ESA’s highly networked facility for designing novel missions, the ‘Miniaturised Asteroid Remote Geophysical Observer’, or M-Argo, is a nanospacecraft based on the CubeSat design employing standardised 10 cm cubic units within which electronic boards can be stacked and subsystems attached.

    M-Argo would be a 12-unit CubeSat – with a 22 x 22 x 34 cm body – that would hitch a ride on the launch of a larger space mission whose trajectory takes it beyond Earth orbit, such as astronomy missions to a Sun–Earth Lagrange point.

    LaGrange Points map. NASA

    The CubeSat would then use its own electric thruster to take it into deep space and rendezvous with an asteroid, which it would survey using a multispectral camera and a laser altimeter. Other miniaturised payloads are also being considered.

    ESA’s Advanced Concepts Team has identified a total of 83 near-Earth asteroids suitable for a CubeSat rendezvous. The study prioritised spinning bodies of around 50 m diameter as a never-before explored class of asteroid, although the target list also includes larger bodies of up to 300 m.

    “For now, M-Argo is just a concept, but provides us very valuable information about technology developments that we need to put in place for a flight demonstration in the near future,” comments Roger Walker, overseeing ESA’s Technology CubeSats.

    “It would cost around a tenth of the smallest deep-space mission to date, democratising space exploration beyond Earth, bringing it into the reach of new actors, in the same way low-Earth orbit has already been opened up by CubeSats.

    “Each time we survey a new asteroid, our understanding of these small bodies has been transformed. With such a cost reduction, we could send 10 to 20 CubeSats to scout different asteroids and build up a wide survey of the near-Earth population, getting to know the neighbours better for the purposes of science and identifying potential in-situ resources for future exploitation.”

    The next step is to undertake supporting research and development through ESA’s General Support Technology Programme, which is tasked with developing promising technologies for space, and identifying a suitable piggyback launch opportunity.

    To become reality, M-Argo would require miniaturised solar electric propulsion, a flat array antenna to boost radio signal gain and an X-band transponder to support communication and ranging to the ground stations back on Earth, as a means of deep-space navigation.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 8:24 am on November 15, 2017 Permalink | Reply
    Tags: , AMAZE, , ESA   

    From ESA: “3D printed metal mutants arise from Europe’s AMAZE programme” 

    ESA Space For Europe Banner

    European Space Agency

    14 November 2017

    6

    1
    3D printed support
    Released 13/11/2017
    Copyright AMAZE – Thales Alenia Space/Renishaw
    Sun sensor and antenna support bracket produced through the AMAZE metal 3D printing programme, courtesy of Thales Alenia Space and Renishaw.

    Europe’s lead in metal 3D printing has been strengthened by the four-year AMAZE programme, producing lighter, cheaper, organically shaped parts. ESA was among 26 academic and industrial partners developing novel processes and products for high-performance sectors.

    Launched in 2013, AMAZE – short for Additive Manufacturing Aiming Towards Zero Waste and Efficient Production of High-Tech Metal Products – was the largest R&D programme for 3D printing ever run.

    ESA helped to initiate the programme, which was funded by the European Commission’s Seventh Framework Programme and coordinated by the UK’s Manufacturing Technology Centre (MTC).

    The Agency joined manufacturers Airbus and Thales Alenia Space in assessing prototype products for space use, while comparable end-users did the same for the automotive, aeronautics and nuclear fusion sectors.

    2
    Laser-based 3D printing
    Released 13/11/2017
    Copyright AMAZE – Fraunhofer ILT/Airbus
    High-rate laser-based laser melting of pylon bracket in Inconel 718 metal, courtesy of Fraunhofer ILT and Airbus

    “The work of AMAZE ranges right across the process chain,” explains David Wimpenny, Chief Technologist for the National Additive Manufacturing Centre, based at the MTC.

    “It includes new approaches to part design, along with the challenge of reliably finishing and inspecting the resulting parts, introducing novel materials, improving production throughput and developing common industrial standards.”

    Tommaso Ghidini, heading ESA’s Structures, Mechanisms and Materials Division, comments: “The Agency’s participation in AMAZE was an opportunity to create synergies and cross-fertilising benefits with our existing Advanced Manufacturing Cross-Cutting Initiative, harnessing game changing manufacturing technologies for space.”

    To draw maximum benefit from the process, parts need to be designed specially. With 3D printing it is only the volume of material being fused together that is paid for, with no waste to be cut away, so the lighter the weight of the part the cheaper it ends up.

    David Wimpenny adds: “It’s really opened the eyes of designers: through 3D printing, complex, performance-optimised, lightweight parts actually end up costing less than traditional alternatives.

    “During AMAZE we’ve been literally growing parts to bear the loads required; the result has been these organically shaped metal parts weighing less than half the of the original component, manufactured all in one – removing joints which represent potential points of weakness.

    3
    3-m-wide titanium cylinder
    Released 13/11/2017
    Copyright AMAZE – ESA/IREPA
    Among the largest items produced by AMAZE, this 3-m diameter structural cylinder was printed in titanium alloy Ti64 using ‘directed energy deposition’ melting powder with a laser, courtesy of ESA and IREPA.

    “This complexity means that file sizes can be huge – several orders of magnitude larger than a normal CAD file – and it can take a long while to process all that data. But another AMAZE development has been new software tools to radically reduce the time involved.”

    New materials were developed to meet specific industrial needs, including the first 3D printing of InVar, an alloy of nickel and iron that is highly prized by the space sector for its ability to withstand orbital temperature extremes without expansion or contraction.

    3D printing of vanadium and tungsten was also demonstrated. These high-melting point metals are suited for use within nuclear fusion reactors as well as rocket engines.

    4
    Temperature-resistant InVar-printed component

    Assessing a range of different 3D printing techniques, the variety of produced parts varied hugely, from millimetre-scale samples to metre-scale structural items.

    “Just as important was increasing the speed and productivity of the process, from a few hundred grams to kilograms per hour, without compromising quality,” explains David Wimpenny.

    “We achieved this in various ways, including increasing the number and power of the lasers used for material melting.”

    4
    Pylon brackets

    “We’ve also worked to ensure the powder feedstock is optimised for the process. The powder particles have to have the correct size and shape to provide the right flow properties to give consistently high-quality, defect-free layers.”

    Another challenge was the post processing, finish and inspection of the parts, including standardised non-destructive test procedures. Medical-style three-dimensional CT scanning is one solution that was explored, with AMAZE findings going towards an ongoing effort to develop a common ISO standard for the field.

    “The industrial partners in the project are now commercialising the results of the project and the AMAZE experience has helped to forge a research community which will continue to increase the knowledge and improve the capability of additive manufacturing processes going forwards”, says David Wimpenny.

    For instance, Norsk Titanium – supported by developments made during AMAZE – has become the first company to manufacture structural aircraft components using metal 3D printing.

    Tommaso explains that the ESA–RAL Advanced Manufacturing Lab at Harwell in the UK, has played an important role in assessing the performance of AMAZE’s aeronautical and space outputs: “It has helped to define verification strategies used for critical applications, putting them on a fast track for adoption by projects.”

    David Wimpenny concludes that AMAZE has helped maintain Europe’s pre-eminence in the field of metal 3D printing, “But we shouldn’t be complacent. Global competition is fierce and it’s critically important Europe maintains its lead.”

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 6:34 pm on November 11, 2017 Permalink | Reply
    Tags: , , , , Enceladus and its interior heat, ESA, ,   

    From ESA via Manu: Enceladus and its interior heat” 


    Manu Garcia, a friend from IAC.

    The universe around us.
    Astronomy, everything you wanted to know about our local universe and never dared to ask.

    Thanks, Manu, ESA did not bother to put this up in English.

    11.7.17

    Gaël Choblet
    Université de Nantes, France
    Email: Gael.Choblet@univ-nantes.fr

    Gabriel Tobie
    Université de Nantes, France
    Email: gabriel.tobie@univ-nantes.fr

    Nicolas Altobelli
    ESA Cassini–Huygens Project Scientist



    Tel: +34 91 813 1201




    Email: nicolas.altobelli@esa.int

    Markus Bauer








    ESA Science Communication Officer









    Tel: +31 71 565 6799









    Mob: +31 61 594 3 954









    Email: markus.bauer@esa.int

    Oficina de Comunicación de ESAC
    Email: comunicacionesac@esa.int

    1
    Image Credit: NASA / JPL-Caltech / Space Science Institute; Inside: LPG-CNRS / U. Nantes / U. Angers. Graphic composition: ESA

    1. passive flow of cold water from the ocean salt to a porous rock core.
    2. The heated water rises in the core in tight tufts and interacts with rocks.
    3. Hotspots on the seabed.
    4. Transport of heat and rocky material across the ocean.
    5. Localized heating in the ocean-ice thins the ice.
    6. jets of water vapor and particles erupt through cracks.

    If the core of Enceladus was porous, tidal friction could generate enough to cause hydrothermal activity inside for thousands of millions of years heat, which would increase their chances of habitability.

    This is what emerges from a new study, published yesterday in Nature Astronomy, which has a first concept that would explain the key features of Enceladus, the Saturnian moon of 500 km diameter observed by the international Cassini spacecraft during its mission , completed last September.

    NASA/ESA/ASI Cassini-Huygens Spacecraft

    Encélado house a salty overall ocean under an ice layer having an average thickness of 20 to 25 km, which would only 1-5 km in the south polar region. There, through fissures in the ice jets water vapor and ice grains they are expelled. The composition of ejecta measured by Cassini, includes salts and silicon powder, suggesting that would be formed by the interaction of warm water at least 90 ° C, with the porous rock core.

    2
    Enceladus plumes.
    Credit: NASA / JPL / SSI.

    That would require a huge source of heat, a hundred times greater than that could generate natural decay of radioactive elements in rocks your core and medium focalizase activity at the South Pole.

    It is believed that the tidal effect on Saturn is responsible for the eruptions that deforms the ice Enceladus by movements of attraction and repulsion along its elliptical path around the giant planet. However, the energy produced by tidal friction on the ice would be too weak by itself to offset the heat loss from the ocean: the moon would have frozen after 30 million years. However, as Cassini has shown, the moon is still extremely active, suggesting that something else is happening.

    “Although it has never been clear what the source of that Enceladus gets the energy to stay active, we have now seen in more detail how the structure and composition of its rocky core could have a key role in generating the energy needed” says lead study author Gaël Choblet, University of Nantes (France).

    In the new simulations, the core is formed of deformable porous unconsolidated rock, water can readily permeate. Thus, the liquid cold ocean water can seep into the core and gradually heated as it penetrates due to tidal friction between moving rock fragments.

    Water circulates through the core and then rises again because it is hotter than the surrounding material. Ultimately, this process transfers heat to the ocean floor in thin columns that interact closely with rocks. On the ocean floor, these columns reach the colder ocean.

    3
    Last observation feathers Enceladus by Cassini .. Credit: NASA / JPL / SSI.

    It is estimated that one hot spot on the ocean floor up to 5 GW release energy equivalent to geothermal energy consumed annually in Iceland. These hot spots seafloor generated columns totaling several centimeters per second. Not only the columns make the icy crust there above is based, also transported for weeks and months, from the ocean floor, small particles which are then released into space in the form of icy jets.

    Also, computer models of the authors show that most of the water is expelled in the polar regions of the moon, with a chain process causing hot spots in localized areas and consequently, a smaller thickness in the ice fair over something that matches interpreted by Cassini.

    “Our simulations can explain both the existence of a global ocean due to heat transport large scale between the depths of the inside and the ice, and the concentration of activity in a region relatively small around the south pole, justifying the main phenomena observed by Cassini, “says study co-author Gabriel Tobie, also of the University of Nantes.

    Scientists say that efficient rock-water interactions in a porous core caused by tidal friction could generate up to 30 GW of heat over tens of millions or even thousands of millions of years.

    “Future missions able to analyze organic molecules columns Enceladus more accurately than Cassini would be able to confirm whether the maintenance of hydrothermal conditions could have permitted the emergence of life,” said Nicolas Altobelli, Cassini project scientist at ESA .

    A future mission equipped with a radar to penetrate the ice, may also limit the thickness of the ice and additional overpasses or orbiter improve models interior, also verifying the presence of active hydrothermal columns.

    “In the next decade, with the Juice mission Jovian moons send new generation instruments, including a ground penetrating radar.

    ESA/Juice spacecraft

    ESA /JUICE schematic

    This mission is specifically devoted to assess the potential for habitability of ocean worlds in the outer solar system, “adds Nicolas.

    Additional Information.
    The article “Powering prolonged hydrothermal activity inside Enceladus,” Choblet G. et al., Was published in Nature Astronomy on November 6, 2017, article online.

    The Cassini-Huygens mission is a cooperative project between NASA, ESA and the Italian space agency ASI.

     
  • richardmitnick 10:02 am on November 10, 2017 Permalink | Reply
    Tags: , , , , , ESA, , Three years of successful operations of the Copernicus Sentinel-1 constellation   

    From ESA: “Earth from Space: special edition” Video 

    Published on Nov 9, 2017

    ESA Space For Europe Banner

    European Space Agency

    Discover more about our planet with the Earth from Space video programme. This special edition celebrates three years of successful operations of the Copernicus Sentinel-1 constellation.

    See the full article here .

    Please help promote STEM in your local schools.

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    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 9:51 am on November 10, 2017 Permalink | Reply
    Tags: 6 x 6 mm prototype chip is now fabricated, , ESA, Microwave radio signals, The alternative solid state solution is often more compact but their gain decreases with frequency, Two types of amplifier: firstly those based on vacuum tube technologies pretty much unbeatable in terms of power and efficiency   

    From ESA: “Delivering signal power to cross space” 

    ESA Space For Europe Banner

    European Space Agency

    9 November 2017

    1
    Natanael Ayllon, payload engineer.

    Microwave radio signals – able to pass freely through Earth’s atmosphere as well as empty space – play a role in just about everything, including mission telemetry and telecommands, satellite services and broadcasting, navigation and timing signals and radar, along with other forms of active remote sensing.

    ESA’s Radio Frequency Technology and Equipment Section works on all types of microwave technologies. I worked there until recently, focused on RF-active technologies such as microwave amplifiers and transmit/receive modules. If a signal going to the ground is going to have sufficient energy that your TV can acquire it, then you need to amplify it at satellite level before it is transmitted down to Earth.

    There are two types of amplifier: firstly, those based on vacuum tube technologies, such as ‘travelling wave tubes’, which are old technology but pretty much unbeatable in terms of power and efficiency, based on the interaction between an electron beam and the RF signal in a vacuum envelope, transferring power from the electron beam into the RF signal, triggering amplification.

    The alternative solid state solution is often more compact. They are based on semiconductor transistors where small variations of the input voltage are translated into larger variations of current at the output. The main issue of these devices is that, contrary to vacuum tube amplifiers, their gain decreases with frequency. You know, electrons prefer vacuum!

    2
    Natanael in Lab

    Our section performs various R&D developments through ESA’s technology programmes, from basic prototyping at low technology readiness levels to facilitating specific applications and also support to projects, to take things from the mid technology readiness levels all the way to launch campaigns. At the moment we’re doing work for ESA’s Biomass mission, designed to track status and dynamics of tropical forests using P-band radar.

    Because this frequency is so low, a vacuum tube amplifier would be too heavy and bulky for the type of satellite we envisage. Instead Biomass has baselined solid state amplifiers using novel high-power semiconductor gallium nitride, harnessed for space through the ESA-led ‘GaN Reliability Enhancement and Technology Transfer Initiative’ (GREAT2) consortium.

    So, while the GaN technology has already been qualified, what we need to do is put that into a hermetically sealed package that can be flown in space – specially tailored to avoid any risk of electrical discharge or similar operating risks – and then put through rigorous lifetime testing to ensure reliability, arriving at a guaranteed mean time to failure.

    After the transistor is packaged, at solid-state power amplifier (SSPA) level we’re concerned about things like overall electrical performance and thermal dissipation, checking that waste heat is carried away without affecting component reliability – along with all the usual qualification steps of vibration, shock and thermal vacuum testing. The mission needs six SSPAs in total, each of these with three packaged GaN transistors inside. Nevertheless we are qualifying a larger amount of packaged transistors to have a safe number of parts.

    For basic research we’re really privileged here at ESTEC, being able to propose new projects to try extend the current worldwide state of the art, using ESA R&D programmes like the Basic Technology Research Programme or Networking/Partnering Initiative to tap into academic expertise to tackle particular problems. As a good example, in 2011 we proposed integrating several functions into a transmit/receive module on a single chip.

    Today that 6 x 6 mm prototype chip is now fabricated – also harnessing GaN – putting together a high-power amplifier, low-noise amplifier, a transmit-receive switch and a calibration coupler: what would normally involve an individual chip or circuit for each of these functions. The concept is applicable to any frequency band. In this case, we demonstrated the concept in C-band (for Sentinel-1) and it yielded three times more output power than the current amplifier on board these satellites, with savings of about 40% in terms of size.

    4
    GaN Single Chip Front End. Released 17/08/2017. Copyright ESA

    There were all kinds of challenges in integrating all these functions on such a small chip. For instance, having the high-power amplifier beside the low-noise amplifier – the heat from the former could for instance compromise the performance of the latter, but we were able to come up with system-level solutions, such as switching off elements when not in use.

    The potential is there for more sensitive radar instruments combining decreased mass or extended duty cycles for future Sentinel-1 follow-ons – here in the Directorate we are further maturing the concept within our General Support Technology Programme.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 10:08 am on November 9, 2017 Permalink | Reply
    Tags: Copernicus, , ESA, Eumetsat,   

    From ESA: “Shared vision strengthens Europe’s space strategy” 

    ESA Space For Europe Banner

    European Space Agency

    8 November 2017

    1
    Earth seen by Meteosat
    Released 22/04/2015
    Copyright Eumetsat

    This full-disc image of Earth was acquired by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) instrument on MSG-3 (now Meteosat-10 in operation) on 22 April 2015.

    Working together for three decades, ESA and Eumetsat have been instrumental in positioning Europe as a leader in observing Earth from space. Continuing to share a vision, the two organisations have signed a statement that will strengthen Europe in meteorology and climate monitoring, and that will help to take the Copernicus programme into the future.

    Thanks to the long-standing cooperation between ESA and Eumetsat, Europe has a fleet of meteorological satellites, both in geostationary orbit hovering 36 000 km above the equator and in polar orbit circling Earth.

    From their different orbital perspectives, these two types of satellite mission provide essential information for weather forecasts and to understand climate change.

    In addition, both organisations play a key role in the European Commission’s environmental monitoring Copernicus programme where ESA develops the suite of Sentinel satellites, which make up the core of this monitoring network, and Eumetsat operates and delivers the data from a number of these missions.

    2
    Statement signature
    Released 08/11/2017
    Copyright ESA

    A statement, signed on 7 November 2017 by ESA’s Director General, Jan Woerner (middle right), and Eumetsat’s Director General, Alain Ratier (middle left), at the European Space Week in Tallinn, Estonia, sets out the organisations’ shared goals for the future and their continued cooperation. The agreement was signed in the presence of Norway’s Deputy Minister of Trade, Industry and Fisheries, Lars Jacob Hiim (left) and Spain’s Secretary General for Industry and SMEs, Begoña Cristeto Blasco (right).

    A statement, signed yesterday by ESA’s Director General, Jan Woerner, and Eumetsat’s Director General, Alain Ratier, at the European Space Week in Tallinn, Estonia, sets out the organisations’ shared goals for the future and their continued cooperation.

    Jan Woerner said, “We have been cooperating with Eumetsat since the 1980s to ensure an excellent source of satellite data for meteorology. We built the first and second generation series of the geostationary Meteosat missions and the series of polar-orbiting MetOp missions, which Eumetsat operates.

    “As our cooperative venture continues, we are now focusing on the two follow-on series, Meteosat Third Generation and MetOp Second Generation, which both offer enhancements and ensure the continuity of essential information for global weather forecasting and climate monitoring for decades to come.

    “As part of our United Space in Europe philosophy, the statement that we have signed is a declaration of our continued commitment to strengthening Europe’s strategy for space.”

    2
    MetOp Second Generation
    Released 08/11/2017
    Copyright ESA

    Building on the current series of MetOp weather satellites, the family of MetOp-Second Generation missions will comprise three pairs of satellites to secure essential data from polar orbit for weather forecasting through the decades beyond 2020.

    Meteosat Third Generation comprises six satellites working in pairs: four imaging and two sounding satellites. The Copernicus Sentinel-4 is to be carried on the sounder satellites.

    MetOp Second Generation is also a series of six satellites that work in pairs: the ‘A’ type carries optical instruments while the ‘B’ type focuses on microwave sensors. The Copernicus Sentinel-5 instrument is to be carried on type A.

    The agreement highlights the importance of space-based data to Europe’s economy and competitiveness. In addition, it will increase European autonomy in security, defence, climate monitoring, and the management of natural disasters.

    Alain Ratier added, “Our cooperation offers meteorological satellite systems that have the highest impact on weather forecasts and that therefore create socio-economic benefits of more than €5 billion a year in the EU.

    “This is the foundation for extending our partnership to atmospheric composition and ocean monitoring for Copernicus, together with the EC.”


    ESA Sentinels (Copernicus)

    For the EC’s Copernicus programme, ESA and Eumetsat seek to ensure a new standard of air-quality forecasting so that Europe can better protect the health of citizens with the Sentinel-4 and Sentinel-5 missions.

    The current Sentinel-3 mission and the future Sentinel-6 mission, which are operated by Eumetsat, are expected to boost the development of operational oceanography, and a 10-year extension of the existing 25-year climate record in light of the implementation of the Paris Agreement.

    In addition, both organisations will coordinate efforts to improve Copernicus data accessibility and user uptake to create new business and innovation opportunities.

    Finally, ESA and Eumetsat will implement plans with the EC on the deployment of additional Sentinel satellites to monitor the oceans and atmosphere, in particular to monitor carbon dioxide.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 9:51 am on November 9, 2017 Permalink | Reply
    Tags: , ESA, ESA’s Large Diameter Centrifuge is about to mark its 10th birthday, GRAVARC TNG team, Ten years of exploring hypergravity with ESA’s centrifuge, The centrifuge has been a place of pilgrimage for European researchers for the last decade   

    From ESA: “Ten years of exploring hypergravity with ESA’s centrifuge” 

    ESA Space For Europe Banner

    European Space Agency

    8 November 2017
    No writer credit

    1

    After 14 million revolutions, ESA’s Large Diameter Centrifuge is about to mark its 10th birthday. The 8 m-diameter four-arm centrifuge gives researchers access to a range of hypergravity up to 20 times Earth gravity for weeks or months at a time.

    At its fastest, the centrifuge rotates at up to 67 revs per minute, with its six gondolas placed at different points along its arms weighing in at 130 kg, and each capable of accommodating 80 kg of payload. Multiply those combined figures by 20 g and it adds up to an equivalent mass of 24 tonnes.

    “The centrifuge’s surrounding walls and bulletproof glass wouldn’t protect us if one of those gondolas ever spun off,” explains Jack van Loon of the centrifuge team. “The glass is only there in case something like a nut or screwdriver gets left on the mechanism by accident.

    “Of course, we have a strict maintenance cycle, checking on vibration and looking out for anything wrong with the motors, gearing and brakes, with visual checks made before each run.

    “Additionally, the centrifuge rests on a seismic block of heavy concrete, making sure its running doesn’t interfere with sensitive instruments in other nearby ESA labs.”

    Based within a scifi-style white dome, the centrifuge has been a place of pilgrimage for European researchers for the last decade, including student experimenters on regular Spin Your Thesis campaigns.

    2
    Plasma arc under ascending hypergravity
    Released 07/02/2014 10:41 am
    Copyright GRAVARC TNG

    The GRAVARC TNG team, made up of three PhD students from Masaryk University in Brno in the Czech Republic) tested the behaviour of gliding arcs of plasma in noble gases under hypergravity conditions. Seen above, the krypton plasma arcs shift lower and lower as the gravity level moves from 1g to 2g to 12g and finally 18g, acquired at 0.3 second intervals. The team’s objective was to improve scientific understanding of the physical phenomena involved. Studying electric discharges at different levels of gravity is important for safety in spaceflight, for the design of ion thrusters, and for the understanding of plasma-related processes in planetary atmospheres.

    Jack adds: “We have some internal ESA testing – for instance to simulate static g loads experienced on some foreign launchers for key satellite systems – as well as a lot of academic teams, especially in the life and physical sciences, plus commercial experiments.”

    Future internal studies will be looking at the behaviour of heat pipes and reactions wheels, used for satellite thermal and attitude control, respectively.

    A lot of factors turn out to shift along with gravity: bubble sizes change, convection currents accelerate and alloys form in novel ways. Electrical plasmas alter and test animals lose fat mass.

    All the computers and associated equipment used in experiments also need checking, because their performance might be degraded too: computers may fail to cool down, standard microscope light sources have been known to flicker.

    3
    Northon college experiment in LDC
    Released 13/05/2015 2:55 pm
    Copyright ESA
    Experiment in gondola

    “Traditionally, scientists have taken the value of gravity for granted as a rigid, fixed number,” adds Jack. “But it isn’t: we’re able to manipulate and modulate the g term within an equation, which offers a lot of new approaches.

    “For many years the scientific community maintained a central focus on microgravity, with the partial gravity of the Moon and Mars emerging as an interest in the recent years. But that’s a very human-centric approach, looking only at the planetary bodies people can inhabit.

    “With this centrifuge, research teams can find out how systems respond across the entire spectrum of gravity, gaining a range of results they can use to validate models, observe the general direction of changes to varying gravity levels, then extrapolate higher or lower as needed.”

    4
    Achilles students and supporting staff pose outside the LDC housing
    Released 07/04/2017
    Copyright ESA

    ESA decided to build the centrifuge to enlarge the array of research infrastructure it could offer the European research community, with the encouragement of the European Low Gravity Research Association and financial backing from the Dutch government.

    ESA’s Life and Physical Sciences Instrumentation section had a long tradition of building small centrifuges flown during space missions, typically offering a 1 g inflight control for microgravity experiments. Designing the centrifuge meant scaling up this approach, with engineering performed by Portuguese machining company Zeugma.

    5
    Graphical view of the LDC when rotating at full speed with 6 gondolas swinging out.
    Released 12/10/2011
    Copyright ESA

    Graphical view of the LDC when rotating at full speed with 6 gondolas swinging out. The 7th gondola for the rotation control and the gas and water bottles compartments are located at the centre of the centrifuge.

    In January ESA will celebrate the centrifuge’s first decade, giving the team the opportunity to hear from their user community on desired future upgrades and new research ideas.

    Further ahead, a next-generation centrifuge has been proposed from an ESA Topical team study: measuring around 200 m in diameter, this “Human Hypergravity Habitat” would be big enough for people to live in a hypergravity environment for months on end.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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