Category Archives: ESA

Wind and Water

First the wind, this is how ESA’s Aeolus satellite will use laser technology to measure the winds to help understand our climate and to improve our weather forecasts.

Next the water, an ESA-backed group, led by TCarta, has developed a way of using data from Low-orbiting satellites equipped with light-measuring sensors to produce water depth maps AND make them available to anyone who could use them.

Both videos copyright by ESA.

Gaia’s Star Density Map

A star density map composed by data obtained from second data release of Gaia – not to mention a very resourceful individual.

ESA: The second data release of ESA’s Gaia mission, made in April, has marked a turning point in the study of our Galactic home, the Milky Way. With an unprecedented catalogue of 3D positions and 2D motions of more than a billion stars, plus additional information on smaller subsets of stars and other celestial sources, Gaia has provided astronomers with an astonishing resource to explore the distribution and composition of the Galaxy and to investigate its past and future evolution.

The majority of stars in the Milky Way are located in the Galactic disc, which has a flattened shape characterised by a pattern of spiral arms similar to that observed in spiral galaxies beyond our own. However, it is particularly challenging to reconstruct the distribution of stars in the disc, and especially the design of the Milky Way’s arms, because of our position within the disc itself.

This is where Gaia’s measurements can make the difference.

This image shows a 3D map obtained by focusing on one particular type of object: OB stars, the hottest, brightest and most massive stars in our Galaxy. Because these stars have relatively short lives – up to a few tens of million years – they are mostly found close to their formation sites in the Galactic disc. As such, they can be used to trace the overall distribution of young stars, star formation sites, and the Galaxy’s spiral arms.

The map, based on 400,000 of this type of star within less than 10 000 light-years from the Sun, was created by Kevin Jardine, a software developer and amateur astronomer with an interest in mapping the Milky Way using a variety of astronomical data.

It is centred on the Sun and shows the Galactic disc as if we were looking at it face-on from a vantage point outside the Galaxy.

To deal with the massive number of stars in the Gaia catalogue, Kevin made use of so-called density isosurfaces, a technique that is routinely used in many practical applications, for example to visualise the tissue of organs of bones in CT scans of the human body. In this technique, the 3D distribution of individual points is represented in terms of one or more smooth surfaces that delimit regions with a different density of points.

Here, regions of the Galactic disc are shown with different colours depending on the density of ionising stars recorded by Gaia; these are the hottest among OB stars, shining with ultraviolet radiation that knocks electrons off hydrogen atoms to give them their ionized state.

The regions with the highest density of these stars are displayed in pink/purple shades, regions with intermediate density in violet/light blue, and low-density regions in dark blue. Additional information from other astronomical surveys was also used to map concentrations of interstellar dust, shown in green, while known clouds of ionised gas are depicted as red spheres.

The appearance of ‘spokes’ is a combination of dust clouds blocking the view to stars behind them and a stretching effect of the distribution of stars along the line of sight.

An interactive version of this map is also available as part of Gaia Sky, a real-time, 3D astronomy visualisation software that was developed in the framework of the Gaia mission at the Astronomisches Rechen-Institut, University of Heidelberg, Germany.

Further details including annotated version of the map: Mapping and visualising Gaia DR2

Credits: Galaxy Map / K. Jardine

Proba’s Solar Eclipses

ESA: Thanks to a quirk of our cosmos, the Moon’s average distance from Earth is just right for it to appear as the same size in the sky as the significantly larger Sun. Once in a while the Moon slides directly between Earth and the Sun such that it appears to cover our star completely, temporarily blocking out its light and creating a total solar eclipse for those along the narrow path cast by the Moon’s shadow.

But sometimes the alignment is such that the Moon only partially covers the Sun’s disc. Such a partial eclipse occurred on Saturday for observers located primarily in northern and eastern Europe, northern parts of North America, and some northern locations in Asia.

ESA’s Sun-watching Proba-2 satellite orbits Earth about 14.5 times per day and with its constant change in viewing angle, it dipped in and out of the Moon’s shadow twice during Saturday’s eclipse.

Selected views of the two partial eclipses are seen side-by-side here – the first (left) was captured at 08:40:12 GMT and the second (right) at 10:32:17 GMT on 11 August.

The images were taken by the satellite’s SWAP camera, which works at extreme ultraviolet wavelengths to capture the Sun’s hot turbulent atmosphere – the corona – at temperatures of about a million degrees, which can be seen in the background.

Watch the full image sequence here.

Image: ESA/Royal Observatory of Belgium

A Bit of Asteroid Itokawa

Along with the likes of the Cassini and Rosetta missions we have the history making Hayabusa Mission. The mission actually returned a sample from the asteroid Itokawa and the mission at least for me showcases the resilience of the JAXA mission team (see the section “Changes in mission plan” in the provided link.

The image above was released yesterday 01 Aug 2018 by ESA.

Here’s the caption included in the release:

ESA: Seen on a microscopic support, this sharp-edged grain of rock is an extraterrestrial object – a tiny sample from the Itokawa asteroid, retrieved by Japan’s Hayabusa mission and now being tested by ESA researchers.

Japan’s Hayabusa spacecraft was the world’s first mission to retrieve samples from the surface of an asteroid and return them to Earth. Beset by many problems, after a seven-year, six-billion-km odyssey Hayabusa returned around 1 500 precious asteroid grains to Earth.

Extremely precious, these Hayabusa grains have become the focus of scientific study around the world – and three of them are currently here, at ESA’s ESTEC technical centre in the Netherlands.

Researcher Fabrice Cipriani is leading research into their static charging properties, to understand the consequences for the surface environments of asteroids.

FENIX The Little Boosters That Can

I love this idea!

ESA: Sometimes the key to innovation is staying simple. Italian tech company D-Orbit applied this principle to their winning product submitted to last year’s Space Exploration Masters.

The competition encourages ideas to solve some of the space industry’s main challenges while fostering products and services with commercial potential.

In the case of D-Orbit’s Fenix propulsion system, the idea was both simple and small. The pen-sized booster prototype, is just 10 cm long and 2 cm wide – allowing small satellites to work smarter and explore farther.

The 10 x 10 x 10 cm CubeSats are deployed directly into orbit from space. They currently have no propulsion system to change orbit or deorbit at the end of their missions. With the FENIX, CubeSats could be employed for longer missions farther out in space.

Each of the four boosters is packed with solid propellant that provides thrust which is triggered by a simple electrical ignition system. The boosters can be configured at each corner of the CubeSat or doubled up on either side. Thanks to their lightweight and compact size, they do not take up much instrument space.

With space exploration opening for business, technologies like Fenix have the potential to expand our horizons farther out in space. CubeSats can take on more sophisticated missions if they can manoeuvre in orbits – such as studying the Moon and asteroids from different angles.

In low Earth orbit, the boosters can deorbit the CubeSats at the end of their missions to help reduce space debris.

D-Orbit won a four-month ticket to test their prototype on the newly-installed ICE Cubes facility in the Columbus module of the International Space Station. The team will test the booster’s safe ignition mechanism inside an ICE cube experiment unit, without firing the actual propulsion system, to ensure that it works and is safe under space conditions.

Sensors and cameras will record the sparks, triggered by an electrical impulse, and the team can observe the testing anytime, anywhere, thanks to ICE Cubes dedicated control centre providing continuous remote access for users on ground. Fenix is set for launch to the Space Station by the end of next year.

Do you have an idea with commercial potential that could innovate space exploration? Submit it to the Space Exploration Masters challenge.

 
Image: ESA

The First P120C Hot Fire

Very impressive! It sounds like the test went fine here are the ESA comments:

Today’s hot firing of the P120C solid-propellant motor at Europe’s Spaceport in French Guiana proves its flight-worthiness for use on Vega-C next year and on Ariane 6 from 2020.

This marks an important milestone in the development schedule of Europe’s new-generation launchers, designed to boost our autonomy in the space arena, and maintain Europe’s global competitiveness.

The test lasted 140 seconds with the motor delivering a maximum thrust of 4650 kN, simulating the complete burn time from liftoff and through the first phase of flight.

No anomalies were seen and the performance met expectations, though full analysis will take several months.

The P120C is 13.5 m long and 3.4 m in (44.3 ft by 12.8 ft) diameter and is made using a carbon composite material and built in one segment. It will replace the current P80 as the first stage motor of Vega-C. Two or four P120Cs will be strapped onto Ariane 6 as boosters for liftoff.

This test was a collaboration between ESA, France’s CNES space agency, and Europropulsion under contract to Avio and ArianeGroup.

The next static firing will occur at the end of this year with the P120C qualification motor.

The Giant PC120C

Meet the giant PC120C; the world’s largest solid rocket motor in once piece and it’s ready for a test fire.

ESA: This week, the largest solid rocket motor ever (built in one piece) will be test fired at Europe’s Spaceport in French Guiana for the first time.

This important milestone validates the booster for use on Vega-C next year and on Ariane 6 from 2020.

Fully loaded with solid fuel, the P120C rocket motor common to Europe’s future launchers Vega-C and Ariane 6, will be held vertically in the test stand and ignited. Sensors will gather about 600 measures during the test.

The P120C is 13.5 m long and 3.4 m in diameter, contains 142 tonnes of solid propellant and provides a maximum thrust of 4615 kN (in vacuum) over a burn time of about 135 s.

The design builds on existing expertise and lessons learned with Vega’s P80 first stage motor. P120C will replace P80 as the first stage motor of Vega-C. Two or four P120Cs will be strapped onto Ariane 6 as boosters for liftoff.

All main components of the motor such as nozzle, igniter, solid propellant, and insulated motor case have already been tested separately. This static firing will prove these technologies, materials and production techniques in combination and validate the behaviour of the assembled motor.

The test stand with the tools and equipment that will secure the P120C for its test firing, have had to be modified or developed to accommodate this huge motor.

Recently a full-scale model of the P120C filled with inert propellant allowed engineers to verify tools, check connections and perfect procedures.

Information gathered during this static firing will allow engineers to compare their numerical models against observed reality to consolidate the P120C design.

This will guide the design of the P120C qualification motor that will be static fired at the end of the year.

Image: ESA