Two Russian spacecraft enjoy a ride over the Alps in this image taken from the International Space Station.
On the left is the Soyuz MS-05 that brought ESA astronaut Paolo Nespoli and fellow crew mates NASA astronaut Randy Bresnik and cosmonaut Sergey Ryazansky to the Station in July.
On the right is the Russian cargo vehicle Progress 68P, which docked to the Station with fresh supplies in mid-October.
Both vehicles will return to Earth in December just a week apart, with the Progress burning up upon reentry and the Soyuz landing in the Kazakh steppe with Paolo, Randy and Sergey.
Southern Italy and Sicily seen by ESA astronaut Paolo Nespoli aboard the International Space Station.
Paolo is currently working and living aboard the International Space Station as part of the Italian Space Agency long duration mission VITA.
Just in time for Halloween this week: a green deep-space tracking station.
This image was taken by Byron Bay-based astrophotographer Dylan O'Donnell in October during a photo shoot at the New Norcia station, some 120 km north of Perth, Western Australia.
The ‘ghostly green’ was created by reflecting a floodlight off the station’s 35 m-diameter deep-space antenna and structure.
The station routinely communicates with spacecraft orbiting Mars as well as ESA’s Gaia and XMM observatory missions. In future, it will link up with BepiColombo at Mercury and the Euclid astronomical observatory.
Since August, the station has been operating in part on a new solar power system, which, together with a local water recycling system, is helping to boost the station’s sustainability and reduce its environmental impact.
In this image from the Copernicus Sentinel-1 satellite mission, we can see the location of the ‘Halloween crack’ on Antarctica’s Brunt Ice Shelf, highlighted in red. The former and current locations of the British Antarctic Survey’s Halley research stations are also marked.
Discovered on 31 October 2016, the swiftly lengthening Halloween crack prompted the temporary withdrawal of staff from the Halley VI research station for the duration of the 2017 Antarctic winter. Information from the Copernicus Sentinel-1 and Sentinel-2 satellites helped in making this decision.
The base had already been moved 23 km inland during last Antarctica’s summer months because another ice chasm (highlighted in red) had begun to show signs of growth.
In this image, Sentinel-1’s radar was also able to pick up lines in the snow and ice marking the researchers’ routes from the former location of the Halley VI station to the coast and to the Halloween crack. To help us identify them, these lines have been coloured in black.
This image was created by combining three Sentinel-1 radar scans in September and October. The colours in the Weddell Sea indicate changes in sea ice between the acquisitions. A ‘polynya’ – an area of open water surrounded by ice – is visible in the lower-central part of the image.
From the fourth most populous city to the rugged Outback, the Sentinel-3A satellite gives us a wide-ranging view over Australia’s southwestern corner.
This perspective from space clearly illustrates human’s influence on our environment: the agricultural landscape that dominates in the lower-left is suddenly interrupted by the more densely vegetated national parks and forests.
The city of Perth is located on the coast along the left edge of the image. About 150 km north of Perth sits ESA’s tracking station at New Norcia, where a 35 m-diameter radio dish communicates with deep-space missions such as Rosetta and Mars Express.
Moving further inland, grasslands give way to the deserts of Australia’s vast and remote interior – known as the Outback – with a landscape dominated by red soil and sparse vegetation. Several large salt lakes are visible across the image in white, including the appropriately named Lake Disappointment by explorer Frank Hann in search of fresh water (top of image).
Clouds over the ocean obstruct our view of the southern coast, but the lack of cloud cover over the interior desert pronounces the dry climate, which is a consequence of global wind patterns.
Sentinel-3 offers a ‘bigger picture’ for Europe’s Copernicus programme by systematically monitoring Earth’s oceans, land, ice and atmosphere to understand large-scale global dynamics.
While the satellite mission carries a suite of cutting-edge instruments, this image, also featured on the Earth from Space video programme, was captured on 9 April 2017 by the satellite’s Ocean and Land Colour Instrument, which helps to monitor ocean ecosystems, supports crop management and agriculture, and provides estimates of atmospheric aerosol and clouds.
This spooky sight, imaged by the NASA/ESA Hubble Space Telescope, resembles fog lit by a streetlamp swirling around a curiously shaped hole – and there is some truth in that. While the ‘fog’ is dust and gas lit up by the star, the ‘hole’ really is an empty patch of sky.
When the dark patch was first imaged, it was assumed to be a very cold, dense cloud of gas and dust, so thick as to be totally opaque in visible light, and blocking all light behind it. In general, such globules are known to be small cocoons of forming stars, but thanks to ESA’s Herschel Space Observatory, which would have been able to see any hints of star formation at infrared wavelengths but did not, along with ground-based observations, it turned out to be a truly empty patch of sky.
Astronomers think that is was formed when jets of gas from some of the young stars in the wider region punctured the sheet of dust and gas that forms the surrounding nebula. The powerful radiation from a nearby mature star may also have helped to clear the hole.
The bright star seen here is V380 Orionis, a young star 3.5 times the mass of our own Sun. It appears white owing to its high surface temperature of about 10 000ºC – nearly twice that of the Sun. The star is so young that it is still surrounded by a cloud of material left over from its formation. This bright material in the area pictured here is only visible because of the light from the star; it does not emit any visible light of its own. This is the signature of a ‘reflection nebula’ – this one is known as NGC 1999.
The Universe contains some truly massive objects. Although we are still unsure how such gigantic things come to be, the current leading theory is known as hierarchical clustering, whereby small clumps of matter collide and merge to grow ever larger. The 14-billion-year history of the Universe has seen the formation of some enormous cosmic structures, including galaxy groups, clusters, and superclusters — the largest known structures in the cosmos!
This particular cluster is called Abell 665. It was named after its discoverer, George O. Abell, who included it in his seminal 1958 cluster catalogue. Abell 665 is located in the well-known northern constellation of Ursa Major (The Great Bear). This incredible image combines visible and infrared light gathered by the NASA/ESA Hubble Space Telescope using two of its cameras: the Advanced Camera for Surveys and the Wide Field Camera 3.
Abell 665 is the only galaxy cluster in Abell’s entire catalogue to be given a richness class of 5, indicating that the cluster contains at least 300 individual galaxies. Because of this richness, the cluster has been studied extensively at all wavelengths, resulting in a number of fascinating discoveries — among other research, Abell 665 has been found to host a giant radio halo, powerful shockwaves, and has been used to calculate an updated value for the Hubble constant (a measure of how fast the Universe is expanding).
This may resemble an alien landscape, but it is actually a microscopic view of tin used to solder electronic components. The long shard rising from the surface is a ‘tin whisker’ – a spontaneous outgrowth representing a clear and present danger to space missions.
The phenomenon was first identified within terrestrial electronics, but these whiskers are known to grow rapidly out of pure tin in the weightlessness, vacuum and temperature extremes of space.
Typically, these crystalline filaments are just a few thousands of a millimetre thick, though may extend more than a thousand times further in length. They are electrically conductive and so can threaten catastrophic short circuits: the US Galaxy IV telecommunications satellite was lost due to this issue in 1998.
The traditional method of preventing tin whiskers was to add lead – but lead is toxic, so its use in solder has been phased out through the EU’s Reduction of Hazardous Substances directive. ESA and European space industry have been granted a waiver to continue using tin–lead alloy for solder, but not an indefinite one.
“We’ve been researching alternative methods to arrest the growth of tin whiskers,” explains ESA materials engineer Jussi Hokka. “We’ve investigated a technique called atomic layer deposition, widely used in the semiconductor industry to lay down a metal oxide film just a few nanometres deep.
“Over a time period of up to a year, this application has led to a significant reduction in the number of tin whiskers, although we don’t yet know if this is due to the surface barrier laid down or some factor of the overall process.”
ESA worked with a consortium led by Finnish specialist Picosun, supported by Finnish packaging specialist Poltronic Ltd and Loughborough University in the UK.
Follow-up research is now underway. Success will undoubtedly have wider applications: tin whiskers are also re-emerging as a problem of terrestrial electronics now that pure tin solder is in widespread use.
ESA’s Tommaso Ghidini comments: “Tin whiskers remain in many respects a mysterious metallurgical phenomenon. But if this technique proves to be successful, we could safely use pure tin as a green option, foregoing carcinogenic lead – not only for space but also for automotive, aeronautics and large other industrial domains, while guaranteeing equivalent engineering performance.”
A prototype rover is commanded to drive in and sample a quarry resembling a lunar site. The image shows a virtual reality impression of the test.
The rover is a key element of the ESA-led Heracles mission in cooperation with the Canadian Space Agency CSA and Japan’s JAXA space agency.
Heracles is studying the potential of human–robot partnerships for exploring the Solar System, beginning with the still-unexplored far side of the Moon. Astronauts tele-operating the rover from lunar orbit will help to select better, more pristine samples to return to Earth.
The test took place in mid-October at St Alphons de Granby quarry in Quebec, Canada. The site was chosen for its Moon-like landscape.
ESA’s control centre in Darmstadt, Germany and CSA took turns operating the vehicle.
An interesting perspective of ESA’s Aeolus satellite before being placed in a thermal–vacuum chamber for testing. Simulating the environment of space, the chamber is used to make sure the satellite will work in space. Aeolus will measure profiles of the world’s winds using novel laser technology. This will not only advance our knowledge of atmospheric dynamics, but also provide much-needed information to improve weather forecasts.
Week in Images
30 October - 3 November 2017