Category Archives: ESA

Aeolus Mission

The Aeolus satellite has reached Europe’s spaceport near Kourou in preparation for a scheduled launch on 21 August 2018. The satellite traveled by ship from Saint Nazare, western France to the Port of Cayenne, French Guiana.

The satellite should provide data on global wind-profiles especially those vertical portions in the lower 30 km. The data on the famous El Nino should be very interesting.

ESA’s Lunar Agenda

The approach ESA is taking is sound, it will be interesting to see what they come up with.

ESA: This image of the Moon was taken by ESA astronaut Alexander Gerst from the International Space Station during his Horizons mission. But he’s not the only one to be eyeing the Moon these days.

From 3 to 5 July, ESA is hosting a workshop on lunar exploration at its technical heart in the Netherlands. Building on ESA’s commitment to sustainable exploration, the workshop brings space experts and industry together to talk lunar resources and how to use them to return humanity to the Moon and farther afield.

For humans to live and work on the Moon and beyond, we need oxygen and water for life support as well as fuel and materials to build habitats and equipment. Launching these bulky consumables would cost the kind of money and energy that makes human exploration of the Solar System unsustainable.

Instead, ESA is looking into the capabilities that would allow humans to harness lunar resources for humanity’s sustainable return to the Moon. The approach is known as In-Situ Resource Utilisation. Put simply, it means extracting and processing resources on site to make useful products and services.

Last year, service providers with like-minded ideas were invited to take place in a one-year study exploring what a collaborative and commercially viable mission to the Moon would look like.

During this week’s workshop ESA is continuing this discussion with experts, industry officials, and potential new partners by exploring the technological readiness, commercial viability, legal status, and international context for lunar resource use.

In the meantime, the humans closest to our rocky satellite – astronauts on the International Space Station – are testing technologies such as remotely operating robots to take us a step closer to our next outpost in space.

Image: ESA / NASA

Stellar Bubble

ESA: 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.

Image: SA/XMM-Newton; J. Toalá; D.Goldman

 

Stellar Nursery

The Herschel Observatory is still responsible for great science even after the four or five-years or so since the end of the mission.

ESA — Stellar nurseries are cloudy and dusty places that shine brightly in infrared light. The G305 star-forming complex is no exception. It features a number of bright, intricate gas clouds heated by infant stars in their midst. In this spectacular image by ESA’s Herschel space observatory, these star-forming hotspots stand out in a blue tone that contrasts with the red-brownish colour of cooler regions.

While there are several star-formation sites dotted throughout this scene, the most striking ones surround the dark, heart-shaped area in the top right of the image. Hidden at the centre of the dark region lie the massive star WR48a and its two neighbours, stellar clusters Danks 1 and 2. All three play an important role in triggering the formation of new stars, even if they themselves are relatively young objects no older than a few million years (for comparison, the Sun is around 4.6 billion years old).

Strong winds and radiation from WR48a and the high-mass stars in the two clusters have pushed away the gas remnants from the cloud where they originated. The swept-away gas, gathered together at the edge of the heart-shaped bubble, is now forming new stars.

Using Herschel, astronomers have identified 16 sites where high-mass stars are forming in this stellar nursery. The region is one of the brightest and most plentiful star-forming complexes in the Milky Way, and an ideal ground to observe and study massive stars at different stages of formation and evolution.

The G305 complex is about 12 000 light-years away and gets its name from its location at around 305º longitude in the plane of our Galaxy. In the night sky, it appears near the Coalsack Nebula, a large interstellar cloud of dust visible to the naked eye and located in the constellation of Crux, the Southern Cross. A very prominent dark nebula, Coalsack shows up in the southern skies as a black patch against the bright, starry backdrop of the Milky Way.

This image, obtained as part of Hi-GAL – the Herschel infrared Galactic Plane Survey, combines observations at three different wavelengths: 70 microns (blue), 160 microns (green) and 250 microns (red).

Launched in 2009, Herschel operated for four years observing at far infrared and submillimetre wavelengths. This spectral range allowed it to observe the glow of dust in gas clouds where stars are born to investigate this process and observe their early evolution.

Image: ESA/Herschel/PACS, SPIRE/Hi-GAL Project. Acknowledgement: UNIMAP / L. Piazzo, La Sapienza – Università di Roma; E. Schisano / G. Li Causi, IAPS/INAF, Italy

The Next Mission for Alexander Gerst

Alexander Gerst will join US astronaut Serena Auñón-Chancellor and Russian cosmonaut Sergei Prokopyev for a trip to the International Space Station from the Baikonur cosmodrome, Kazakhstan in the Soyuz MS-09. Gerst will take command of the space station.

Rotation of the LMC

Wow, what a sight! One day I hope to see the Large Magellanic Cloud, someday perhaps I can do this when I take my “bucket list” ride on The Ghan.

ESA:

Last week the much-awaited second slew of data from ESA’s Gaia mission was released, providing information on a phenomenal 1.7 billion stars – the richest star catalogue to date.

To put that vast number into context, if you were to count ‘only’ to one billion at a rate of one count per second, it would take more than 30 years. The new data will surely keep astronomers busy for even longer.

The dataset has already revealed 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 treasure trove of data also includes information about stars beyond our own Galaxy. One example is illustrated in this image, which focuses on one of the nearest galaxies to our Milky Way, the Large Magellanic Cloud, or LMC.

This image combines the total density of stars detected by Gaia in each pixel with information about the proper motion of stars – their velocity across the sky – which is represented as the texture of the image, giving it a fingerprint-like appearance.

Measuring the proper motion of several million stars in the LMC, astronomers were able to see an imprint of the stars rotating clockwise around the centre of the galaxy. The impression of motion is evoked by the swirling nature of the line texture.

Astronomers are interested to derive the orbits of globular clusters – ancient systems of stars bound together by gravity and found in the halo of the Milky Way – and dwarf galaxies that revolve around the Milky Way. This will provide all-important information to study the past evolution of our Galaxy and its environment.

A similar view based on the total amount of radiation detected by Gaia and colour information about the stars is available here, and an animated view of the rotation of stars within the Large Magellanic Cloud is available here.

Read more about Gaia’s latest data release here.

Acknowledgement: Gaia Data Processing and Analysis Consortium (DPAC); A. Moitinho / A. F. Silva / M. Barros / C. Barata, University of Lisbon, Portugal; H. Savietto, Fork Research, Portugal; P. McMillan, Lund Observatory, Sweden

Image: ESA/Gaia/DPAC

Gaia’s Second Data Release

Based on observations between July 2014 to May 2016, the second release helped produce a catalog of over 500,000,000 start! The catalog includes the most accurate information yet on the positions, brightness, distance, motion, colour and temperature of stars in the Milky Way as well as information on asteroids and quasars.

Sentinel 3B Launching Today

Launching later today (if all goes well of course) from the Plesetsk Cosmodrome in Russia is ESA’s Sentinel 3B. Coverage begins at 17:30 UT / 14:30 ET.

ESA’s caption: The Copernicus Sentinel-3B rocket at the top of the launch tower. The Copernicus Sentinel-3B satellite is scheduled for liftoff on 25 April 2018 from the Plesetsk cosmodrome in northern Russia. Its identical twin, Sentinel-3A, has been in orbit since February 2016. The two-satellite constellation offers optimum global coverage and data delivery for Europe’s Copernicus environment programme.

Image: ESA–S. Corvaja

Waiting For Gaia

Every now and then you will read my lamenting how we need better distance measurements. You might think we know the distances to distant stars, after all we reference distances. The trouble is those measures are only accurate in the broadest sense – we really do need more accuracy.

Gaia aims to change all that! ESA just posted this excellent overview of the Gaia mission.