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  • richardmitnick 1:38 pm on June 16, 2018 Permalink | Reply
    Tags: , , , , ESA, , NGC 3199, , WR18 (Wolf-Rayet 18)   

    From European Space Agency: “Star-circling bubble of gas” 

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    From European Space Agency

    1
    Star-circling bubble of gas
    11/06/2018
    ESA/XMM-Newton; J. Toalá; D.Goldman

    ESA/XMM Newton

    This turbulent celestial palette of purple and yellow shows a bubble of gas named NGC 3199, blown by a star known as WR18 (Wolf-Rayet 18).

    Wolf-Rayet stars are massive, powerful, and energetic stars that are just about reaching the end of their lives. They flood their surroundings with thick, intense, fast-moving winds that push and sweep at the material found there, carving out weird and wonderful shapes as they do so. These winds can create strong shockwaves when they collide with the comparatively cool interstellar medium, causing them to heat up anything in their vicinity. This process can heat material to such high temperatures that it is capable of emitting X-rays, a type of radiation emitted only by highly energetic phenomena in the Universe.

    This is what has happened in the case of NGC 3199. Although this kind of scenario has been seen before, it is still relatively rare; only three other Wolf-Rayet bubbles have been seen to emit X-rays (NGC 2359, NGC 6888, and S308). WR18 is thought to be a star with especially powerful winds; once it has run out of material to fuel these substantial winds it will explode violently as a supernova, creating a final breath-taking blast as it ends its stellar life.

    This image was taken by the European Photon Imaging Camera (EPIC) on ESA’s XMM-Newton X-ray space observatory, and marks different patches of gas in different colours. The incredibly hot, diffuse, X-ray-emitting gas within the Wolf-Rayet bubble is shown in blue, while a bright arc that is visible in the optical part of the spectrum is traced out in shades of yellow-green (oxygen emission) and red (sulphur emission).

    This blue and yellow-green component forms an optical nebula – a glowing cloud of dust and ionised gases – that stretches out towards the western end of the X-ray bubble (in this image, North is to the upper left). This lopsided arc caused astronomers to previously identify WR18 as a so-called runaway star moving far faster than expected in relation to its surroundings, but more recent studies have shown that the observed X-ray emission does not support this idea. Instead, the shape of NGC 3199 is thought to be due to variations in the chemistry of the bubble’s surroundings, and the initial configuration of the interstellar medium around WR18.

    Explore this object in ESASky.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    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 1:25 pm on June 16, 2018 Permalink | Reply
    Tags: , , , BepiColombo, , ESA, Hand-sewn insulation blankets   

    From European Space Agency: “Hand-sewn insulation blankets” 

    ESA Space For Europe Banner

    From European Space Agency

    1
    Hand-sewn insulation blankets
    12/06/2018
    ESA–B. Guillaume

    One of the main activities in recent weeks for the BepiColombo team at Europe’s Spaceport in Kourou has been the installation of multi-layered insulation foils and sewing of high-temperature blankets on the Mercury Planetary Orbiter.

    The insulation is to protect the spacecraft from the extreme thermal conditions that will be experienced in Mercury orbit.

    While conventional multi-layered insulation appears gold-coloured, the upper layer of the module’s striking white high-temperature blanket provides the focus of this image.

    The white blankets are made from quartz fibres. Because the fabric is not electrically conductive, to control the build-up of electrostatic charge on the surface of the spacecraft, conducting threads have been woven through the outer layer every 10 cm. The edges of the outer blanket are hand-sewn together once installed on the module, as seen in this image.

    The face of the spacecraft the engineer is working on is the panel that will always look at Mercury’s surface and as such many of the science instruments are focused here. This includes the orbiter’s cameras and spectrometers, a laser altimeter and particle analyser.

    The panel also has fixtures to connect the module to the Transfer Module during the cruise to Mercury.

    The face of the spacecraft pointing to the left in this orientation is the spacecraft radiator, which will eventually be fitted with ‘fins’ designed to reflect heat directionally, allowing the spacecraft to fly at low altitude over the hot surface of the planet. Heat generated by spacecraft subsystems and payload components, as well as heat that comes from the Sun and Mercury and ‘leaks’ through the blankets into the spacecraft, will be conducted to the radiator by heat pipes and ultimately radiated into space.

    The oval shapes correlate to star trackers, used for navigation, while a spectrometer is connected with ground support equipment towards the top. At the back of this face, the magnetometer boom can be seen folded against the spacecraft – it has now also been fitted with multi-layered insulation.

    For more images of the launch preparations at Kourou visit the BepiColombo image gallery.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    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 11:32 am on June 6, 2018 Permalink | Reply
    Tags: , , , , , ESA, Ice Cube experiments   

    From European Space Agency: “ICE Cubes space research service open for business” 

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    From European Space Agency

    5 June 2018

    1
    20/06/2017
    ESA
    A new European commercial service is allowing researchers, educators, universities and companies to run their experiments on the International Space Station. Dubbed Ice Cubes, budding space researchers can build their experiment in blocks of 10 x 10 x 10 cm that slot into a dedicated rack on ESA’s space laboratory Columbus.

    Similar to small ‘CubeSats’ that orbit Earth, Ice Cube experiments can be made from ‘commercial off the shelf’ products and be stacked together to allow for larger experiments if needed.

    The Ice Cube unit in this image is installed on the experiment rack in a full-size mockup of the Columbus laboratory at ESA’s technical heart in the Netherlands.

    Due to their high degree of modularity and use of off-the-shelf subsystems, Ice Cubes projects are ‘plug and play’ and can be readied for flight more rapidly compared to traditional space experiment schedules. The first Ice Cubes will be running next year.

    The service is being offered by Space Applications Services in partnership with ESA, ensuring years of spaceflight know-how to help researchers, educators and companies develop and build safe and useful experiments – including a discount for educational users.

    More information and how to get started is available on the Ice Cubes website, let the space science begin!

    The first European facility for commercial research on the International Space Station was installed today in Europe’s space laboratory Columbus. The International Commercial Experiments service – ICE Cubes for short – offers fast, simple and affordable access for research and technology experiments in microgravity.

    NASA astronaut Ricky Arnold installed the ice-box-sized facility in the European Physiology Module in the Columbus laboratory. ICE Cubes gets its power, temperature regulation and communications from Columbus.

    The facility hosts experiments designed around 10 cm cubes (1U) or combinations of this volume – there is room for 12 cubes on top and two rows of four cubes below. Experiments can also float freely through the Columbus laboratory and communicate wirelessly with the facility to send data to Earth.

    The first experiments are going to be launched on the next SpaceX Dragon supply vessel scheduled for launch this month. Designed to be plug-and-play, the experiment cubes only need to be slotted into the facility for them to work.

    The first ICE Cubes experiments from the International Space University highlight the versatility of the service. One will investigate plant biology, another will bio-mine with microbes, and a third merges the arts and science by using a person’s heart rate to change a piece of kaleidoscopic artwork.

    The ICE Cubes service is based on a partnership with Space Applications Services and is part of ESA’s human and robotic exploration strategy to ensure access to the weightless research possibilities in low Earth orbit.

    2
    Columbus laboratory

    From idea to reality in a year, anybody’s experiment can be launched to the Space Station. Service launches occur typically three times a year. With one point of contact and over two decades of space research know-how, getting an experiment designed, built and in compliance with International Space Station standards has never been easier.

    The price starts from €50 000 for a 1-kg experiment with an end-to-end service package running for four months, with cheaper rates for educational organisations.

    3
    ICE Cubes control centre

    ICE Cubes offers unprecedented 24-hour direct access to its experiments via a dedicated mission control centre at Space Applications Services’ premises in Sint-Stevens-Woluwe, Belgium. Clients can connect at any time to their experiment from their own location over internet to read the data and even send commands directly.

    The experiments themselves will be highlighted on the ESA website over the next few weeks. Visit the ICE Cubes service website for more information and contact details.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    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 1:12 pm on May 14, 2018 Permalink | Reply
    Tags: ESA, , , ,   

    From European Space Agency: “Our galaxy’s heart” 

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    From European Space Agency

    14/05/2018

    Milky Way NASA/JPL-Caltech /ESO R. Hurt

    1
    ESO/ATLASGAL consortium; ESA/Planck

    ESO APEX Telescope ATLASGAL Large Area Survey of the Galaxy

    ESO/APEX high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft)

    ESA/Planck 2009 to 2013

    At first glance, this image may resemble red ink filtering through water or a crackling stream of electricity, but it is actually a unique view of our cosmic home. It reveals the central plane of the Milky Way as seen by ESA’s Planck satellite and the Atacama Pathfinder Experiment (APEX), which is located at an altitude of around 5100m in the Chilean Andes and operated by the European Southern Observatory.

    This image was released in 2016 as the final product of an APEX survey mapping the galactic plane visible from the southern hemisphere at submillimetre wavelengths (between infrared and radio on the electromagnetic spectrum). It complements previous data from ESA’s Planck and Herschel space observatories.

    Planck and APEX are an ideal pairing. APEX is best at viewing small patches of sky in great detail while Planck data is ideal for studying areas of sky at the largest scales. It covers the entire sky – no mean feat. The two work together well, and offer a unique perspective on the sky.

    This image reveals numerous objects within our galaxy. The bright pockets scattered along the Milky Way’s plane in this view are compact sources of submillimetre radiation: very cold, clumpy, dusty regions that may shed light on myriad topics all the way from how individual stars form to how the entire Universe is structured.

    From right to left, notable sources include NGC 6334 (the rightmost bright patch), NGC 6357 (just to the left of NGC 6334), the galactic core itself (the central, most extended, and brightest patch in this image), M8 (the bright lane branching from the plane to the bottom left), and M20 (visible to the upper left of M8). A labelled view can be seen here.

    Planck was launched on 14 May 2009 and concluded its mission in October 2013. The telescope returned a wealth of information about the cosmos; its main aim was to study the Cosmic Microwave Background (CMB), the relic radiation from the Big Bang. Among other milestones, Planck produced an all-sky map of the CMB at incredible sensitivity and precision, and took the ‘magnetic fingerprint’ of the Milky Way by exploring the behaviour of certain light emitted by dust within our galaxy.

    Its observations are helping scientists to explore and understand how the Universe formed, its composition and contents, and how it has evolved from its birth to present day.

    APEX is a collaboration between the Max Planck Institute for Radio Astronomy, the Onsala Space Observatory, and the European Southern Observatory, ESO. The telescope is operated by ESO.

    See the full article here .

    Please help promote STEM in your local schools.

    stem

    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 1:25 pm on May 11, 2018 Permalink | Reply
    Tags: , , , , ESA, ESA Test Centre in the Netherlands, ESA’s shaker tables, Shaker test of 8-tonne cooling system   

    From European Space Agency: “Shaker test of 8-tonne cooling system” 

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    From European Space Agency

    09/05/2018

    1
    Shaker test of 8-tonne cooling system
    ESA–G. Porter, CC BY-SA 3.0 IGO

    Typically ESA’s shaker tables are used to replicate the take-off vibrations of a satellite-lifting rocket. The large object seen here is not a satellite at all but an 8-tonne cooling system being subjected to a simulated earthquake – while blasting a chilly wave of air towards the engineer observing the test.

    Manufactured by Munters in Belgium, this mammoth 6 x 4 x 5 m cooling system is designed to remove heat from industrial-scale data centres while using just a fifth of the energy of traditional designs.

    The system travelled three hours by road to ESA’s Test Centre in Noordwijk, the Netherlands, for testing to prove it can carry on running even in the midst of an earthquake with a peak ground acceleration of 1G on 3 axes – equivalent to a violent Level IX earthquake, stronger than the Fukushima earthquake of 2011.

    “To export to the Japanese market we have to satisfy very stringent seismic testing requirements,” says Craig MacFadyen of Munters. “We need to show the cooling system doesn’t fall to pieces and maintains its functionality during different grades of earthquakes.”

    Testing was performed on ESA’s Hydra multi-axis hydraulic shaker, the Test Centre’s single most powerful shaker.

    “Hydra’s hydraulic actuators move an 18-tonne shaker table in all three orthogonal axes simultaneously, in a similar fashion to an aircraft flight simulator,” explains Alexander Kuebler of ETS, the company operating the Test Centre for ESA.

    “The motion of these actuators is overseen by a network of 36 parallel computers. The entire installation is braced by a seismic mass supported by springs and shock absorbers to prevent the resulting earthquake-strength vibrations spreading through the rest of the Test Centre. Up to 512 acceleration measurement channels can be used during testing, acquiring the maximum possible data for the customer.”

    Hydra has served many of Europe’s largest space missions, including Envisat – at 8 tonnes the largest-ever civil Earth observation satellite – Herschel, and the Automated Transfer Vehicle, which weighed 22 tonnes at launch.

    Hydra can also accommodate non-space customers when its schedule allows, such as the testing of generators for the underside of trains and an Airbus fuselage to simulate the stresses of approach and landing.

    ESA’s Test Centre in the Netherlands is the largest facility of its kind in Europe, providing a complete suite of equipment for all aspects of satellite testing under a single roof.

    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 4:39 pm on May 5, 2018 Permalink | Reply
    Tags: DEEP SPACE STATIONS READY FOR NASA'S INSIGHT MRS FLIGHT, ESA,   

    From European Space Agency: ESA DEEP SPACE STATIONS READY FOR NASA’S INSIGHT MARS FLIGHT” 

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    From European Space Agency

    4 May 2018
    No writer credit

    1
    New Norcia

    NASA’s latest mission to Mars begins tomorrow. ESA deep space ground stations in Australia and South America will track the InSight spacecraft on NASA’s behalf as it begins its cruise to the Red Planet.

    Set to be launched from Vandenburg Air Force Base in California on an Atlas V at 1105 UTC (1305 CEST) on Saturday, InSight will bring a lander to Mars to study its interior, with equipment to measure internal heat and detect ‘marsquakes’. InSight’s 485-million km journey to Mars will take about six months, beginning soon after it separates from its launcher in Earth orbit.

    Five hours after launch, ESA’s deep space ground station at New Norcia in Western Australia, will pick up the signal from InSight. It will maintain contact as a ‘hot backup’ at the same time as NASA’s own Deep Space Network ground station at Canberra, over on the easterly side of the continent.

    Once Canberra loses contact, the 35-m dish antenna at New Norcia will maintain contact with the mission until it vanishes under the horizon. ESA’s second southern-hemisphere deep space ground station at Malargüe in Argentina will pick up the contact two and a half hours after that.

    NASA Mars Insight Lander

    “Our stations at New Norcia and Malargüe will allow NASA to keep in touch with InSight during its critically important ‘launch and early operations’ phase, when the spacecraft systems are first turned on and checked,” explains Daniel Firre, the Agency’s ESA-NASA cross-support service manager.

    “NASA requested this support because at this time of year the southern hemisphere has very good visibility of the trajectory to Mars, and by extension the NASA DSN stations at Madrid and Goldstone have poor visibility to no visibility in the early days after launch, which leaves only its remaining DSN station at Canberra.

    “This is based on a long-standing cross-support agreement between ESA and NASA, where we provide tracking station support to one another as needed. And by extension, as New Norcia monitors InSight telemetry NASA will be filling in for ESA missions normally served from there, such as ESA’s star-mapping Gaia.”

    ESA/GAIA satellite

    2
    Malargüe

    InSight’s separation from its upper stage and initial determination of its orbital path will be carried out from Goldstone in California. The role of New Norcia and Malargüe will be to monitor the spacecraft as it departs Earth and to receive essential telemetry, allowing the early identification of any possible problems.

    Should the mission team based at NASA’s Jet Propulsion Laboratory require any corrective telecommands to be uplinked to InSight then they would make a request to ESA’s ESOC European Space Operations Centre in Darmstadt, Germany, which is staffed 24 hrs/day and manages all ESA Estrack stations, including New Norcia and Malargüe.

    “Our support for InSight extends for the first 30 days after launch, but the period of our ‘critical support’ lasts until 0530 UTC on Sunday,” adds Yves Doat, heading ESA’s Ground Facilities Infrastructure Section.

    “During this time we will have local maintenance support in place at New Norcia, to immediately remedy any technical problems that might arise, and a station engineer will also be supporting the team at ESOC.”

    “During the critical phase after launch we will be listening out not for one spacecraft but three,” adds Daniel.“InSight itself is accompanied by a pair of CubeSats called MarCOs, which will be monitoring InSight’s own atmospheric entry, descent and landing to return data direct to Earth as they pass by Mars.

    “All three spacecraft will be near enough together that we should receive them in the same beam.”

    After the first month of interplanetary travel, InSight’s will be easier to track from the northern hemisphere, but New Norcia will go on to play a role in monitoring InSight’s landing on 26 November 2018.

    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 11:10 am on April 26, 2018 Permalink | Reply
    Tags: , , , , ESA,   

    From European Space Agency: “GAIA CREATES RICHEST STAR MAP OF OUR GALAXY AND BEYOND” 

    ESA Space For Europe Banner

    European Space Agency

    25 April 2018

    Markus Bauer
    Head of the Joint Communication Office
    European Space Agency

    Tel: +31 71 565 6799

    Mob: +31 61 594 3 954

    Email: markus.bauer@esa.int

    Anthony Brown
    Leiden Observatory, Leiden University
    Leiden, The Netherlands
    Email: brown@strw.leidenuniv.nl

    Antonella Vallenari
    INAF, Astronomical Observatory of Padua
    Italy
    Email: antonella.vallenari@oapd.inaf.it

    Timo Prusti
    Gaia Project Scientist
    European Space Agency
    Email: timo.prusti@esa.int

    Fred Jansen
    Gaia mission manager
    European Space Agency
    Email: fjansen@cosmos.esa.int

    1
    Gaia’s sky in colour

    ESA’s Gaia mission has produced the richest star catalogue to date, including high-precision measurements of nearly 1.7 billion stars and revealing previously unseen details of our home Galaxy.

    ESA/GAIA satellite

    A multitude of discoveries are on the horizon after this much awaited release, which is based on 22 months of charting the sky. The new data includes positions, distance indicators and motions of more than one billion stars, along with high-precision measurements of asteroids within our Solar System and stars beyond our own Milky Way Galaxy.

    Preliminary analysis of this phenomenal data reveals fine details about the make-up of the Milky Way’s stellar population and about how stars move, essential information for investigating the formation and evolution of our home Galaxy.

    “The observations collected by Gaia are redefining the foundations of astronomy,” says Günther Hasinger, ESA Director of Science.

    2
    The Galactic census takes shape

    “Gaia is an ambitious mission that relies on a huge human collaboration to make sense of a large volume of highly complex data. It demonstrates the need for long-term projects to guarantee progress in space science and technology and to implement even more daring scientific missions of the coming decades.”

    Gaia was launched in December 2013 and started science operations the following year. The first data release, based on just over one year of observations, was published in 2016; it contained distances and motions of two million stars.

    The new data release, which covers the period between 25 July 2014 and 23 May 2016, pins down the positions of nearly 1.7 billion stars, and with a much greater precision. For some of the brightest stars in the survey, the level of precision equates to Earth-bound observers being able to spot a Euro coin lying on the surface of the Moon.

    With these accurate measurements it is possible to separate the parallax of stars – an apparent shift on the sky caused by Earth’s yearly orbit around the Sun – from their true movements through the Galaxy.

    The new catalogue lists the parallax and velocity across the sky, or proper motion, for more than 1.3 billion stars. From the most accurate parallax measurements, about ten per cent of the total, astronomers can directly estimate distances to individual stars.

    “The second Gaia data release represents a huge leap forward with respect to ESA’s Hipparcos satellite, Gaia’s predecessor and the first space mission for astrometry, which surveyed some 118 000 stars almost thirty years ago,” says Anthony Brown of Leiden University, The Netherlands.

    Anthony is the chair of the Gaia Data Processing and Analysis Consortium Executive, overseeing the large collaboration of about 450 scientists and software engineers entrusted with the task of creating the Gaia catalogue from the satellite data.

    “The sheer number of stars alone, with their positions and motions, would make Gaia’s new catalogue already quite astonishing,” adds Anthony.

    “But there is more: this unique scientific catalogue includes many other data types, with information about the properties of the stars and other celestial objects, making this release truly exceptional.”

    SOMETHING FOR EVERYONE

    The comprehensive dataset provides a wide range of topics for the astronomy community.

    As well as positions, the data include brightness information of all surveyed stars and colour measurements of nearly all, plus information on how the brightness and colour of half a million variable stars change over time. It also contains the velocities along the line of sight of a subset of seven million stars, the surface temperatures of about a hundred million and the effect of interstellar dust on 87 million.

    Gaia also observes objects in our Solar System: the second data release comprises the positions of more than 14 000 known asteroids, which allows precise determination of their orbits. A much larger asteroid sample will be compiled in Gaia’s future releases.

    Further afield, Gaia closed in on the positions of half a million distant quasars, bright galaxies powered by the activity of the supermassive black holes at their cores. These sources are used to define a reference frame for the celestial coordinates of all objects in the Gaia catalogue, something that is routinely done in radio waves but now for the first time is also available at optical wavelengths.

    3
    Cosmic scales covered by Gaia

    Major discoveries are expected to come once scientists start exploring Gaia’s new release. An initial examination performed by the data consortium to validate the quality of the catalogue has already unveiled some promising surprises – including new insights on the evolution of stars.

    Galactic archaeology

    “The new Gaia data are so powerful that exciting results are just jumping at us,” says Antonella Vallenari from the Istituto Nazionale di Astrofisica (INAF) and the Astronomical Observatory of Padua, Italy, deputy chair of the data processing consortium executive board.

    “For example, we have built the most detailed Hertzsprung-Russell diagram of stars ever made on the full sky and we can already spot some interesting trends. It feels like we are inaugurating a new era of Galactic archaeology.”

    4
    Hertzsprung-Russell diagram

    Named after the two astronomers who devised it in the early twentieth century, the Hertzsprung-Russell diagram compares the intrinsic brightness of stars with their colour and is a fundamental tool to study populations of stars and their evolution.

    A new version of this diagram, based on four million stars within five thousand light-years from the Sun selected from the Gaia catalogue, reveals many fine details for the first time. This includes the signature of different types of white dwarfs – the dead remnants of stars like our Sun – such that a differentiation can be made between those with hydrogen-rich cores and those dominated by helium.

    Combined with Gaia measurements of star velocities, the diagram enables astronomers to distinguish between various populations of stars of different ages that are located in different regions of the Milky Way, such as the disc and the halo, and that formed in different ways. Further scrutiny suggests that the fast-moving stars thought to belong to the halo encompass two stellar populations that originated via two different formation scenarios, calling for more detailed investigations.

    “Gaia will greatly advance our understanding of the Universe on all cosmic scales,” says Timo Prusti, Gaia project scientist at ESA.

    “Even in the neighbourhood of the Sun, which is the region we thought we understood best, Gaia is revealing new and exciting features.”

    GALAXY IN 3D

    5
    Rotation of the Large Magellanic Cloud

    For a subset of stars within a few thousand light-years of the Sun, Gaia has measured the velocity in all three dimensions, revealing patterns in the motions of stars that are orbiting the Galaxy at similar speeds.

    Future studies will confirm whether these patterns are linked to perturbations produced by the Galactic bar, a denser concentration of stars with an elongated shape at the centre of the Galaxy, by the spiral arm architecture of the Milky Way, or by the interaction with smaller galaxies that merged with it billions of years ago.

    At Gaia’s precision, it is also possible to see the motions of stars within some globular clusters – ancient systems of stars bound together by gravity and found in the halo of the Milky Way – and within our neighbouring galaxies, the Small and Large Magellanic Clouds.

    Gaia data were used to derive the orbits of 75 globular clusters and 12 dwarf galaxies that revolve around the Milky Way, providing all-important information to study the past evolution of our Galaxy and its environment, the gravitational forces that are at play, and the distribution of the elusive dark matter that permeates galaxies.

    “Gaia is astronomy at its finest,” says Fred Jansen, Gaia mission manager at ESA.

    “Scientists will be busy with this data for many years, and we are ready to be surprised by the avalanche of discoveries that will unlock the secrets of our Galaxy.”

    The data from Gaia’s first release can be accessed at http://archives.esac.esa.int/gaia

    The content of the second Gaia release was presented today during a media briefing at the ILA Berlin Air and Space Show in Germany.

    A series of scientific papers describing the data contained in the release and their validation process will appear in a special issue of Astronomy & Astrophysics.

    A series of 360-degree videos and other Virtual Reality visualisation resources are available at http://sci.esa.int/gaia-vr

    Gaia is an ESA mission to survey more than one billion stars in our Galaxy and its local neighbourhood in order to build the most precise 3D map of the Milky Way and answer questions about its structure, origin and evolution.

    A large pan-European team of expert scientists and software developers, the Data Processing and Analysis Consortium, located in and funded by many ESA member states, is responsible for the processing and validation of Gaia’s data, with the final objective of producing the Gaia Catalogue. Scientific exploitation of the data will only take place once they are openly released to the community.

    More data releases will be issued in future years, with the final Gaia catalogue to be published in the 2020s. This will be the definitive stellar catalogue for the foreseeable future, playing a central role in a wide range of fields in astronomy.

    Gaia was originally planned for a five-year mission, operating until mid-2019. ESA has already approved an indicative extension until the end of 2020, which is up for confirmation at the end of this year.

    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 11:12 am on April 19, 2018 Permalink | Reply
    Tags: , , , , , ESA, GomX-4 cubesat pair   

    From European Space Agency: “ESA’s GomX-4B CubeSat relaying data across space from Danish twin” 

    ESA Space For Europe Banner

    European Space Agency

    18 April 2018

    1
    GomX-4B

    ESA’s latest mission has completed its in-orbit commissioning. The cereal-box-sized GomX-4B performed a transfer of data across hundreds of kilometres of space from its Danish twin.

    On 2 February, the two GomX-4 CubeSats piggybacked to space into a 500 km altitude near-polar orbit after launch on a Long March 2D rocket from Jiuquan, in China’s Gobi Desert.

    Both of the nanosatellites were built by GomSpace in Denmark. GomX-4A, financed by the Danish Ministry of Defence, is focused on monitoring and imaging Denmark’s Arctic territory. The ESA-backed GomX-4B is testing a micro-propulsion system as well as an inter-satellite radio link with its counterpart. It also carries other technology payloads, including a hyperspectral imager.

    CubeSats are small satellites based around standard 10cm cubic units, but these two ‘six-unit’ CubeSats still required weeks of in-orbit testing once they reached space, just like full-sized missions.

    3
    CubeSats GomX-4A and B transfer data between themselves and down to their ground station in Aalborg, Denmark, during a live press conference by manufacturer GomSpace on 12 April 2018.

    GomX-4A carries no thrusters but the agile GomX-4B used its micro-thrusters to shift its orbit relative to its twin. The satellites drifted up to 2000 km apart along their orbit, then GomX-4B performed a series of manoeuvres to reduce the separation distance back to 300 km. This allowed the pair to begin testing their radio link across various distances up to 750 km away. Later in the mission, this distance will be increased up to 4500 km for extended range tests.

    Demonstrating transfer of data between the satellites is extremely valuable. First, it increases opportunities to get images and data down to the ground from the two satellites. But it also points to future possibilities – when an inter-linked constellation of nanosatellites could cover much more territory than any single satellite, and return data to users on the ground much faster, often making it more useful.

    GomSpace showed the satellites in action for the first time during a live press conference from their Aalborg headquarters on 12 April. The retrieval process from GomX-4A to GomX-4B – and vice versa – down to Earth went according to schedule, confirming the satellite pair can share both data and images and send them home.

    4
    GomX-4 pair. ESA’s biggest small satellite yet: the GomX-4B six-unit CubeSat will 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 in 2015. 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. GomX-4B will be launched and flown together with GomX-4A on 2 February 2018, 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 demonstrated on GomX-3, while their separation on their shared orbit will be 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.

    “By having the two CubeSats operating together we’ve gained a lot of extra opportunities for in-orbit testing,” explains Roger Walker, who oversees ESA’s technology CubeSats.

    “We’re very pleased with the results of the commissioning phase, which shows that both GomX-4 CubeSats are working well, individually and together. GomX-4B’s six technology payloads are also working well. We’re now really looking forward to the next six months of the planned mission. The team will be running a series of demanding experiments with the payloads to test their performance in space.”

    5
    Ground antenna for CubeSats. Antenna on the roof of the GomSpace headquarters in Aalborg, Denmark, used to link and downlink data from the GomX-4 pair of CubeSats.

    GomX-4B’s HyperScout imager, manufactured by cosine Research in the Netherlands, made its own first-light image during the commissioning process.

    In addition, a miniaturised star tracker, developed by Innovative Solutions In Space in the Netherlands, also produced its first image of stars. Star trackers help spacecraft to see where they are in space, and the miniature version will undergo further testing and work with the satellite’s attitude control system to improve its pointing accuracy.

    “The GomX-4B satellite is our most advanced nanosatellite design to date,” comments Niels Buus, heading GomSpace.

    “We are pleased ESA is participating in a project which, for the first time, shows how to exploit the benefits of nanosatellite tandem formation. The platform and technology have a lot to offer to our customers and we therefore expect a lot of commercial benefit moving forward. This is definitely a next-generation nanosatellite.”

    The GomX-4B satellite and many of the payloads were funded through the ‘Fly’ element of ESA’s General Support Technology Programme dedicated to small in-orbit technology demonstration missions.

    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 8:53 am on April 19, 2018 Permalink | Reply
    Tags: , , , , ESA, ,   

    From ESA: “Where is the Universe’s missing matter?” 

    ESA Space For Europe Banner

    European Space Agency

    18 April 2018

    Jiangtao Li
    University of Michigan, USA
    Email: jiangtal@umich.edu
    Tel: 734-383-2089

    Joel Bregman
    University of Michigan, USA
    Email: jbregman@umich.edu
    Tel: 734-764-2667

    Norbert Schartel
    XMM-Newton Project Scientist
    European Space Agency
    Email: norbert.schartel@esa.int

    1
    Searching galactic haloes for ‘missing’ matter. No image credit.

    ESA/XMM Newton

    Astronomers using ESA’s XMM-Newton space observatory have probed the gas-filled haloes around galaxies in a quest to find ‘missing’ matter thought to reside there, but have come up empty-handed – so where is it?

    All the matter in the Universe exists in the form of ‘normal’ matter or the notoriously elusive and invisible dark matter, with the latter around six times more prolific.

    Curiously, scientists studying nearby galaxies in recent years have found them to contain three times less normal matter than expected, with our own Milky Way Galaxy containing less than half the expected amount.

    Caterpillar Project A Milky-Way-size dark-matter halo and its subhalos circled, an enormous suite of simulations . Griffen et al. 2016

    “This has long been a mystery, and scientists have spent a lot of effort searching for this missing matter,” says Jiangtao Li of the University of Michigan, USA, and lead author of a new paper http://iopscience.iop.org/article/10.3847/2041-8213/aab2af/meta .

    “Why is it not in galaxies — or is it there, but we are just not seeing it? If it’s not there, where is it? It is important we solve this puzzle, as it is one of the most uncertain parts of our models of both the early Universe and of how galaxies form.”

    Rather than lying within the main bulk of the galaxy, the part can be observed optically, researchers thought it may instead lie within a region of hot gas that stretches further out into space to form a galaxy’s halo. These hot, spherical haloes have been detected before, but the region is so faint that it is difficult to observe in detail – its X-ray emission can become lost and indistinguishable from background radiation. Often, scientists observe a small distance into this region and extrapolate their findings but this can result in unclear and varying results.

    Jiangtao and colleagues wanted to measure the hot gas out to larger distances using ESA’s XMM-Newton X-ray space observatory. They looked at six similar spiral galaxies and combined the data to create one galaxy with their average properties.

    “By doing this, the galaxy’s signal becomes stronger and the X-ray background becomes better behaved,” adds co-author Joel Bregman, also of the University of Michigan.

    “We were then able to see the X-ray emission to about three times further out than if observing a single galaxy, which made our extrapolation more accurate and reliable.”

    Massive and isolated spiral galaxies offer the best chance to search for missing matter. They are massive enough to heat gas to temperatures of millions of degrees so that they emit X-rays, and have largely avoided being contaminated by other material through star formation or interactions with other galaxies.

    Still missing

    The team’s results showed that the halo surrounding galaxies like the ones observed cannot contain all of the missing matter after all. Despite extrapolating out to almost 30 times the radius of the Milky Way, nearly three-quarters of the expected material was still missing.

    Milky Way Dark Matter Halo Credit ESO L. Calçada

    There are two main alternative theories as to where it could be: either it is stored in another gas phase that is poorly observed – perhaps either a hotter and more tenuous phase or a cooler and denser one – or within a patch of space that is not covered by our current observations or emits X-rays too faintly to be detected.

    Either way, since the galaxies do not contain enough missing matter they may have ejected it out into space, perhaps driven by injections of energy from exploding stars or by supermassive black holes.

    “This work is important to help create more realistic galaxy models, and in turn help us better understand how our own Galaxy formed and evolved,” says Norbert Schartel, ESA XMM-Newton project scientist. “This kind of finding is simply not possible without the incredible sensitivity of XMM-Newton.”

    “In the future, scientists can add even more galaxies to our study samples and use XMM-Newton in collaboration with other high-energy observatories, such as ESA’s upcoming Advanced Telescope for High-ENergy Astrophysics, Athena, to probe the extended, low-density parts of a galaxy’s outer edges, as we continue to unravel the mystery of the Universe’s missing matter.”

    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 7:10 am on April 12, 2018 Permalink | Reply
    Tags: , , , , ESA, , Mars Express v2.0   

    From ESA: “Mars Express v2.0” 

    ESA Space For Europe Banner

    European Space Agency

    11 April 2018

    Every so often, your smartphone or tablet receives new software to improve its functionality and extend its life. Now, ESA’s Mars Express is getting a fresh install, delivered across over 150 million km of space.

    With nearly 15 years in orbit, Mars Express – one of the most successful interplanetary missions ever – is on track to keep gathering critical science data for many more years thanks to a fresh software installation developed by the mission teams at ESA.

    The new software is designed to fix a problem that anyone still using a five-year-old laptop knows well: after years of intense usage, some components simply start to wear out.

    The spacecraft arrived at Mars in December 2003, on what was planned to be a two-year mission. It has gone on to spend more than 14 years gathering a wealth of data from the Red Planet, taking high-resolution images of much of the surface, detecting minerals on the surface that form only in the presence of water, detecting hints of methane in the atmosphere and conducting close flybys of the enigmatic moon, Phobos.

    Today, Mars Express is in good shape, with only some minor degradation in performance, but its gyroscopes are close to failing.

    Gyros Gone Bad

    These six gyros measure how much Mars Express rotates about any of its three axes. Together with the spacecraft’s two startrackers, they determine its orientation in space.

    This is critical for pointing its large parabolic radio antenna towards Earth and to aim its instruments – like the high-resolution stereo camera – at Mars.

    Startrackers are simple, point-and-shoot cameras that capture images of the background star field and, with some clever processing, are used to determine the craft’s orientation in space every few seconds.

    The rotation information from the gyros fills in the information between these snapshots and also when the trackers lose track of the stars – which can last for minutes or even hours.


    This movie, based on images taken by ESA’s Mars Express, highlights Mawrth Vallis, a 600 km-long, 2 km-deep outflow channel at the boundary of the southern highlands and the northern lowlands of Mars.
    The movie begins at the mouth of the channel in Chryse Planitia, and heads towards the apparent source region in the Arabia Terra highlands.
    The 4 billion year-old plateau is characterised by many impact craters, indicative of its great age.
    Zooming in, patches of light and dark deposits are revealed. The light-toned layered sediments are among the largest outcrops of clay minerals – phyllosilicates – on Mars. Their presence indicates the presence of liquid water in the past.
    The variety of water-bearing minerals and the possibility that they might contain a record of an ancient, habitable environment on Mars led scientists to propose Mawrth Vallis as a candidate landing site for the ExoMars 2020 mission.
    The animation is based on a colour mosaic and digital terrain model derived from data collected by the high-resolution stereo camera on Mars Express and released earlier this year.

    “After looking at variations in the intensity of the gyros’ internal lasers, we realised last year that, with our current usage, four of the six gyros were trending towards failure,” says spacecraft operations manager James Godfrey.

    “Mars Express was never designed to fly without its gyros continuously available, so we could foresee a certain end to the mission sometime between January and June 2019.”
    The background is based on an actual image of Mars taken by the spacecraft’s high resolution stereo camera.

    Engineers knew, however, from long experience with similar gyros on previous missions, including Rosetta and ERS-2, that it might be possible to fly the mission primarily using its startrackers, with the gyros only being switched on occasionally, to extend their lives.
    “Flying on startrackers with the gyros mostly switched off meant that a significant portion of the 15 year-old software on Mars Express would have to be rewritten, and this would be a major challenge,” says operations engineer Simon Wood.

    While the spacecraft’s builder provided great assistance, it was mostly up to the teams at ESA to open the code, rewrite the software, test it and prepare it for upload as soon as possible.

    “We were also helped by being able to take code flown on Rosetta and transplant it into the Mars Express guidance software,” adds Simon.

    A massive, multi-month effort followed, involving teams from across the Agency working to develop the new software that would enable Mars Express to keep flying. This also meant significant changes in instrument science planning.

    “We didn’t know if such a massive revision was possible – it hadn’t been done before, especially as we would be in a race against time to complete it. But faced with the almost-certain end of mission, what began as wild speculation during a tea break one afternoon last summer has led to the full rewrite now being ready to send up.”

    The new software was finalised earlier this year, and has undergone meticulous testing to ensure it will work as intended.

    Go/No-Go

    The effort came to fruition yesterday, when the mission team met for a critical go/no-go meeting with the ESA managers to get final approval to activate the new software.

    The new code was actually uploaded to an area of spare memory on Sunday, but just like when your phone or tablet gets a software upgrade, mission controllers will have to shut Mars Express down and trigger a reboot to start running the new code, a critical step set for 16 April.

    If all goes as expected, the mission teams will then spend about two weeks testing and reconfiguring the spacecraft to ensure everything is working as it should before resuming normal science operations.

    “Similar, but much smaller fixes, have been developed in the past for other missions with old gyros, such as Rosetta, but this is certainly the most complex and extensive software rewrite we’ve done in recent memory,” says mission manager Patrick Martin.

    “Thanks to the skill of ESA’s teams, Mars Express will fly well into the 2020s, depending on fuel supply, and continue delivering excellent science for many years yet.

    “I look forward to seeing continued joint science campaigns between Mars Express and other Mars missions like ESA’s Trace Gas Orbiter and incoming rover missions.”

    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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