Captured at 14:09 GMT on 29 February 2016 just two weeks after launch, the first image from the Copernicus Sentinel-3A satellite shows the transition from day to night over Svalbard, Norway. As well as showing the snow-covered archipelago, the image also details Arctic sea ice and some cloud features. The image was taken by the satellite’s Ocean and Land Colour Instrument, which features 21 distinct bands, a resolution of 300 m and a swath width of 1270 km. The instrument’s new eyes on Earth will allow ocean ecosystems to be monitored, support vegetation, crop conditions and inland water monitoring. It will also provide estimates of atmospheric aerosol and clouds, all of which bring significant benefits to society through more informed decision-making. Sentinel-3A’s instrument package also includes a Sea and Land Surface Temperature Radiometer, a Synthetic Aperture Radar Altimeter and a Microwave Radiometer.
Featuring southern Spain, Portugal and North Africa, this is one of the first images from the Sentinel-3A satellite. The image was taken by the satellite’s Ocean and Land Colour Instrument on 1 March 2016 and clearly shows the Strait of Gibraltar between the Atlantic and Mediterranean. Swirls of sediment and algae in the seawater can be seen along the southwest coast of Spain and along the coast of Morocco.
Acquired at 17:44 GMT on 29 February 2016 just two weeks after launch, this is one of the first images from Sentinel-3A taken by the satellite’s Ocean and Land Colour Instrument. It features California, Arizona and Mexico. It also captures Los Angeles, which coincidently is where the International Ocean Colour Coordinating Group Meeting is taking place.
In this false colour image from 20 August, Sentinel-2A brings us to Utah’s Salt Lake City and surroundings.
Utah’s capital in the United States, Salt Lake City, sits at 1300 m, bordered by the waters of the Great Salt Lake and the peaks of the Wasatch Range, which rise over 1.6 km above the Salt Lake valley floor.
The Great Salt Lake, partly visible on the left side of the image, is the largest salt-water lake in the Western Hemisphere. Owing to its shallowness, its size shifts substantially. The lighter blue areas denote solar evaporation ponds at the edges of the lake, which produce salts and brine.
The lake contributes an estimated $1.3 billion annually to Utah's economy, comprising the harvesting of brine shrimp, industry in mineral extraction, and recreation.
Although it has been referred to as "America's Dead Sea”, the lake provides habitat for millions of native birds, brine shrimp, shorebirds and waterfowl.
In 1904, the Southern Pacific Causeway was built to create a shorter route across the lake, visible across the top part. This acts as a dam, where the northern end of the lake became more saline than the southern since the Jordan, Weber and Bear lakes all flow southwards.
To appreciate this better, we can compare the natural colour composite of the same area. Using this band combination the variations in the water are more evident, however, the drawback is that we lose the efficiency of the infrared band in monitoring vegetation.
The mountains and several parks appear in varying shades of red, owing to this false-colour band combination. This indicates how sensitive the multispectral instrument on Sentinel-2A is to differences in chlorophyll content, providing key information on vegetation health.
The scattered greys and whites visible along the centre of the image are the City of Salt Lake, home to some 190 000 people and to important mining operations in its surroundings, which produce copper, gold, platinum, silver, lead, and zinc among others, along with various salts from the lake.
This image is also featured on the Earth from Space video programme.
A powerful combination of tectonic activity and strong winds have joined forces to shape the scenery in this region of Mars.
The image was taken by ESA’s Mars Express on 7 July 2015 and covers part of the Aeolis Mensae region. It straddles the transitional region between the southern hemisphere highlands and the smooth, northern hemisphere lowlands.
Several fracture zones cross this region, the result of the martian crust stretching apart under tectonic stress. As it did so, some pieces of the crust sheared away and became stranded, including the large block in the centre of the image.
This flat-topped block, some 40 km across and rising some 2.5 km above the surrounding terrain, is one such remnant of the crust’s expansion. Its elevation is the same as the terrain further to the south, supporting the idea that it was once connected.
Over time, the stranded blocks and their associated landslides have been eroded by wind and possibly flowing water.
Towards the north (right) it becomes apparent that wind is the dominant force. Hundreds of sets of ridges and troughs known as ‘yardangs’ are aligned in southeasterly to northwesterly, reflecting the course of the prevailing wind over a long period of time.
One small steep-sided feature set perpendicular to the main direction of the yardangs is prominent in the lower right of the image. This ridge is evidently made of harder and more resistant rock that has allowed it to withstand the erosive power of the wind.
This image was first published on the DLR website on 21 December 2015.
On 29 February a test model of Orion’s solar array was unfolded at NASA’s Plum Brook Station test facility in Sandusky, Ohio to check everything works as expected. The solar panels were made by Airbus Defence and Space in the Netherlands for the ESA module that will supply power and life support for up to four astronauts.
Each wing stretches more than 7 m, folded inside the Space Launch Systems rocket that will launch the spacecraft on its first unmanned mission in 2018. Orion sports four wings of three panels with 1242 cells per panel to provide 11.1 kW of power – enough to run two typical European households. The distinctive X-wings are an evolution and improvement of ESA’s Automated Transfer Vehicle.
The test was passed with flying colours as the 260 kg array unfurled into its flight configuration. The stresses of flying to the Moon and beyond – and back again – mean the array is designed to bend up to 60º forward and backward, much like a bird in flight.
“That broad movement meant we had to design the wing with thickened solar panels and reinforced hinges and beams, which required extensive testing,” says Arnaud de Jong, head of the Airbus Defence and Space Solar Array team in Leiden, the Netherlands.
The wing tips are expected to deflect more than a metre. A camera on each wing tip, looking back at the spacecraft, will closely monitor the movement.
Further tests will look at how the solar array handles acoustic shocks, vibrations and other shock tests in the following months.
The ExoMars 2016 spacecraft composite, comprised of the Trace Gas Orbiter and Schiaparelli, seen during the encapsulation within the launcher fairing. The conical shape to the left is the launch vehicle adapter, through which the spacecraft is attached to the Breeze upper stage. The first half of the fairing has already been rolled into place underneath the spacecraft assembly, and the second fairing half is being manoeuvred into place by an overhead crane.
The image was taken on 2 March at the Baikonur cosmodrome, Kazakhstan.
The largest sound horn feeding into ESA’s Large European Acoustic Facility – seen here during its installation in 1990 – which is used to subject satellites to a noise level equivalent to a rocket launch.
LEAF is an integral part of ESA’s ESTEC test centre in Noordwijk, the Netherlands, a collection of spaceflight simulation facilities under a single roof. One wall of the chamber – which stands 11 m wide, 9 m deep and 16.4 m high – is embedded with a set of enormous sound horns. Nitrogen shot through the horns can produce a range of noise up to more than 154 decibels, like standing close to multiple jets taking off.
As a safety feature, LEAF can operate only once all the doors are closed. Steel-reinforced concrete walls safely contain its noise, coated with epoxy resin to reflect noise to produce a uniform sound field within the chamber. The chamber itself is supported on rubber bearing pads to isolate it from its surroundings.
Mars Express, ESA’s deep-space probe orbiting the Red Planet, carries a Visual Monitoring Camera that originally provided simple, low-resolution photos of the separation of the Beagle lander. It was then switched off, its prime assignment fulfilled.
In 2007, it was recommissioned as the ‘Mars Webcam’ and has since then provided a wealth of Mars images, including whole-planet views and images of the Mars crescent and limb not otherwise obtainable.
Imaging slots are scheduled on a time-available basis so as not to interfere with the probe’s scientific instruments, and image sets are delivered only after science data have been downloaded.
The camera was off for several months during the recent eclipse season, when Mars Express passes through the planet’s shadow during part of each orbit. This reduces the overall power available on board the spacecraft, meaning the camera can’t be used.
However, it returned to action this week, delivering a set of 10 images on Tuesday, which were acquired around 18:00 GMT the previous evening.
The image above is a ‘stack’ created by amateur photographer Dylan O’Donnell, in Australia. He used nine of the 10 to build a composite that removes some of the noise, blemishes and artefacts inherent to the native images.
VMC images have become very popular with amateur astronomers, photographers, planetologists and Mars enthusiasts, who have used them to create artistic reworks and even to conduct scientific analysis of martian clouds, atmosphere and surface features.
In 2015, ESA’s international #VMCSchools campaign invited students and youth groups to submit observation proposals, identifying the martian feature they wished to image in a scientific or artistic project. Proposals were accepted from Europe, the US, Argentina and Australia.
OSIRIS narrow-angle camera image taken on 27 February 2016, when Rosetta was 29.7 km from Comet 67P/Churyumov–Gerasimenko. The scale is 0.53 m/pixel.
More details via the OSIRIS Image of the Day website.
Showcased at the centre of this NASA/ESA Hubble Space Telescope image is an emission-line star known as IRAS 12196-6300.
Located just under 2300 light-years from Earth, this star displays prominent emission lines, meaning that the star’s light, dispersed into a spectrum, shows up as a rainbow of colours marked with a characteristic pattern of dark and bright lines. The characteristics of these lines, when compared to the “fingerprints” left by particular atoms and molecules, can be used to reveal IRAS 12196-6300’s chemical composition.
Under 10 million years old and not yet burning hydrogen at its core, unlike the Sun, this star is still in its infancy. Further evidence of IRAS 12196-6300’s youth is provided by the presence of reflection nebulae. These hazy clouds, pictured floating above and below IRAS 12196-6300, are created when light from a star reflects off a high concentration of nearby dust, such as the dusty material still remaining from IRAS 12196-6300’s formation.
The precursor laser technology to the EDRS SpaceDataHighway relayed a radar scan of the Brazilian coast to the DLR German Aerospace Center mere seconds after it was collected. It was then processed in a record-breaking 13 minutes, showing the surrounding ships just five minutes later.
The information was gathered by Sentinel-1A over the South Atlantic and collected by the TDP1 payload on Alphasat via laser beam. It was immediately relayed to the ground and processed into a usable image in 13 minutes by DLR in Oberpfaffenhofen and Neustrelitz, Germany. The ships in the image were identifiable just five minutes later, representing the first quasi-realtime end-to-end delivery of a processed ‘synthetic aperture radar’ image and ship detection information in an area far from a ground station.
One of EDRS’s services is to assist maritime surveillance with near- and quasi-realtime ship detection data. Eighteen minutes from collect to processing is well within the sector’s needs to react to rapidly evolving situations like oil spills, illegal migration and piracy. Without EDRS, the time between the data being collected and the satellite passing over a ground station can be more than an hour.
Week In Images
29 February - 4 March 2016