ESA astronaut Alexander Gerst captured this image of the aurora borealis over Europe from the International Space Station and shared it on his social media channels saying: "The vision itself is less important than the visionary spirit – Buckminster Fuller."
The Copernicus Sentinel-2A satellite takes us over Mount Triglav in Slovenia. At 2800 m above sea level, the mountain is the highest in the country and a significant source of national pride, even featuring on the Slovenian coat of arms. Milan Kucan, the former president, famously once said that it was the duty of every countryman and woman to scale the mountain at least once in their lives.
The snow-peaked mountain is visible in the centre of the image, flanked by the popular tourist resort of Bled to the west. This small town is a popular base for skiers in the winter and for water-sport enthusiasts in the summer who make the most of the alpine lake of the same name.
In the lower-right part of this true-colour image, we see the capital of Slovenia, Ljubljana, home to just under 300 000 people and the cultural, administrative and economic centre of the country. Famous for its environmental credentials, the city was named European Green Capital in 2016. This is thanks to shifting the focus from car transport to public transport, by pedestrianising areas of the city and by taking concerted efforts to preserve and protect green areas.
Slovenia is bordered by Austria, Italy, Croatia and Hungary. On the top-right of the image we can see Klagenfurt, the capital city of the southern Austrian province of Carinthia, located by Lake Wörthersee. Sometimes referred to as the Caribbean of the Alps, the Lake area is where the famous Austrian composer, Gustav Mahler, wrote some of his best-known symphonies.
Sentinel-2 data can be used to monitor agriculture, biodiversity, and coastal and inland waters, helping to supply the coverage and data delivery needed for Europe’s Copernicus environmental monitoring programme.
This image, which was captured on 6 May 2018, is also featured on the Earth from Space video programme.
ESA astronaut Alexander Gerst captured this image of the Russian Cosmonaut during the spacewalk of 11 December 2018 and shared it on his social media channels saying: "Isn’t it amazing the environments in which humans can live if they try hard?"
An image of Comet 46P/Wirtanen taken by Abel De Burgos Sierra from La Palma, in the Canary Islands, Spain, on 6 December 2018.
The comet nucleus is at the core of the brightest spot at the centre of the image, and the green diffuse cloud is its coma. The green colour is caused by molecules – mainly CN (cyanogen) and C2 (diatomic carbon) – that are ionised by sunlight as the comet approaches the Sun.
The comet reached perihelion, the closest point to the Sun along its orbit, on Wednesday 12 December, and is on the way to its closest approach to Earth this weekend, when it might become visible to the naked eye from dark locations.
A bright comet with a period of 5.5 years, 46P had been chosen in the 1990s as the target of ESA’s Rosetta mission. However, a launch delay prompted the mission team to select a new target, Comet 67P/Churyumov–Gerasimenko, which was visited by Rosetta between 2014 and 2016.
This image is a composite of three 10 second exposures using R, G, B filters on a Teleskop Service 130 f/5.7, using an Atik 460EX-M CCD. The field of view spans 58 arcmin x 46 arcmin.
Full story: December comet brings back Rosetta memories
Multiple integrated circuits destined to serve as the brains of Europe’s future space missions, etched together onto single pieces of silicon.
These 20-cm diameter wafers each contain 35 replicas of five different space chips, each incorporating as many as 10 million transistors or basic circuit switches.
Laid down within a microchip, these designs endow a space mission with the ability to perform various specialised tasks such as data handling, communications processing or attitude control.
To save money on the high cost of fabrication, various chips designed by different companies and destined for multiple ESA projects are crammed onto the same silicon wafers, etched into place at specialised semiconductor manufacturing plants.
Subjected to various testing procedures the chips on the wafer are chopped up and packaged for use, then mounted on printed circuit boards for connection with other microelectronic components aboard a satellite. Visitors to ESA’s ESTEC technical centre can see some of these silicon wafers exhibited along the establishment’s main corridor.
Since 2002, ESA’s Microelectronics section has maintained a catalogue of ‘building blocks’ for chip designs, known as intellectual property cores, available to European industry through ESA licence. For more information, check this recently updated overview of which ESA IP cores are available and how they can be requested and licenced.
Sometimes it’s all about perspective. This very convincing image of a conjoined moon masquerading as a snowman is actually two separate Saturnian moons – Dione and Rhea – taken from such an angle by the international Cassini spacecraft that they appear as one.
Dione (top) was actually closer to the spacecraft at the time the image was taken, at around 1.1 million kilometres, compared to Rhea (bottom) which was around 1.6 million kilometres from Cassini. Dione has a diameter of 1123 kilometres and Rhea is larger with a diameter of 1528 kilometres, but they appear to have a similar size in this image due to the difference in distance.
The moons also orbit Saturn at different distances: Dione lies at roughly the same distance as the Moon from the Earth and orbits around the ringed planet in just 2.7 days, while Rhea sits slightly further away and has a 4.5 day orbit.
Dione has a large crater called Evander, centred at the south polar region, which allows the two moons to blend seamlessly together in this view. They also have a similar reflectivity, contributing to the snowman-like appearance, while also pointing to a comparable surface composition.
Dione is made of around one third rock, comprising the core, and two thirds ice with a suspected subsurface ocean.
Interestingly, the moon is more heavily cratered on the hemisphere that faces away from the direction of motion compared to the hemisphere that faces the direction of motion, opposite to what is expected as the forward facing side of the moon should be bombarded with more material. This unusual cratering pattern suggests that it suffered an impact which spun the moon around 180 degrees.
Rhea is Saturn’s second largest moon, after Titan, and is similar to Dione in density, but is around one quarter rock mixed with three quarters ice – a giant frozen dirty snowball.
The image was taken on 27 July 2010 by Cassini in visible light using the narrow-angle camera. The resolution is seven kilometres per pixel on Dione and ten kilometres per pixel on Rhea. Saturn is towards the right and out of view. The Cassini mission is a cooperative project of NASA, ESA and Italy’s ASI space agency. The mission concluded in September 2017.
ESA astronaut Alexander Gerst tweeted this image of Lake Dukan in northeast Iraq, asking “What is planet Earth trying to tell us?”
On the heels of COP 24, the United Nations Climate Change Conference that took place last week in Katowice, Poland, it is very clear what Alexander is trying to tell us.
From his vantage point on the International Space Station, Alexander shares his daily views of Earth, as well as his perspective. His imagery captures not only the beauty of Earth but also the fragility. “It is crystal clear from up here that everything is finite on this little blue marble in a black space, and there is no planet B,” he said in a recorded message to kick off the start of the conference.
During this festive season Lake Dukan brings a Christmas tree to mind. The reality behind it is less cause for celebration.
Global warming is dramatically altering habitats and landscapes. What started with melting polar ice is quickly becoming a global problem, as rising sea levels and warmer global temperatures trigger devastating weather phenomena and large-scale habitat destruction.
While organisations such as the United Nations, in global collaboration with governments and agencies monitoring climate change, work to breathe life into the 2015 Paris Agreement, there is much individuals can do to be part of the solution.
This holiday season you can help reduce waste and the stress it puts on our planet. When gifting consider upcycling old toys or purchasing second hand furniture. Making gifts is also a creative option, or give the gift of your time by volunteering to help a friend or a cause, or treat loved ones to an event. Going into the new year, commit to doing a little more to help our planet by recycling, reusing or reducing overall waste.
EDRS-C is shown during the vibration tests at IABG Ottobrunn, in preparation for launch.
EDRS-C is the second node to the European Data Relay System, a unique public–private partnership between ESA and Airbus.
The system – dubbed the SpaceDataHighway by industry – provides data relay between low orbiting satellites and the EDRS nodes over optical links, with the information sent down to Europe in near-real time.
EDRS-C is the first dedicated EDRS satellite, and will double the system's capacity in orbit.
It is built by OHB System AG.
This stunning spiral galaxy is Messier 100 in the constellation Coma Berenices, captured here by the NASA/ESA Hubble Space Telescope — not for the first time. Among Hubble’s most striking images of Messier 100 are a pair taken just over a month apart, before and after Servicing Mission 1, which took place 25 years ago in December 1993.
After Hubble was launched, the astronomers and engineers operating the telescope found that the images it returned were fuzzy, as if it were out of focus. In fact, that was exactly what was happening. Hubble’s primary mirror functions like a satellite dish; its curved surface reflects all the light falling on it to a single focal point. However, the mirror suffered from a defect known as a spherical aberration, meaning that the light striking the edges of the mirror was not travelling to the same point as the light from the centre. The result was blurry, unfocused images.
To correct this fault, a team of seven astronauts undertook the first Servicing Mission in December 1993. They installed a device named COSTAR (Corrective Optics Space Telescope Axial Replacement) on Hubble, which took account of this flaw of the mirror and allowed the scientific instruments to correct the images they received. The difference between the photos taken of Messier 100 before and after shows the remarkable effect this had, and the dramatic increase in image quality.
COSTAR was in place on Hubble until Servicing Mission 4, by which time all the original instruments had been replaced. All subsequent instrumentation had corrective optics built in.
This new image of Messier 100 taken with Hubble’s Wide Field Camera 3 (WFC3), demonstrates how much better the latest generation of instruments is compared to the ones installed in Hubble after its launch and after Servicing Mission 1.
Week in images
10 - 14 December 2018