Mars dust storm

The high resolution stereo camera on board ESA’s Mars Express captured this impressive upwelling front of dust clouds – visible in the right half of the frame – near the north polar ice cap of Mars in April this year.

It was one of several local small-scale dust storms that have been observed in recent months at the Red Planet, which is currently enduring a particularly intense dust storm season. A much larger storm emerged further southwest at the end of May and developed into a global, planet-encircling dust storm within several weeks.

The intensity of this major event means very little light from the Sun reaches the martian surface, a situation extreme enough that NASA’s 15-year old Opportunity rover has been unable to recharge its batteries and call home: it has been in hibernation mode since mid-June.

Dust storms on Mars occur regularly during the southern summer season when the planet is closer to the Sun along its elliptical orbit. The enhanced solar illumination causes stronger temperature contrasts, with the resulting air movements more readily lifting dust particles from the surface – some of which measure up to about 0.01 mm in size.

Martian dust storms are very impressive, both visually like in this image and in terms of the intensity and duration of the rarer global events, but they are generally weaker compared to hurricanes on Earth. Mars has a much lower atmospheric pressure – less than one hundredth of Earth’s atmospheric pressure at the surface – and martian storms have less than half the typical wind speeds of hurricanes on Earth.

The current storm is being monitored by five ESA and NASA orbiters, while NASA’s Curiosity rover has been observing it from the ground thanks to its nuclear-powered battery. Understanding more about how global storms form and evolve will be critical for future solar-powered missions to Mars.

This colour image was created using data from the nadir channel, the field of view of which is aligned perpendicular to the surface of Mars, and the colour channels of the high-resolution stereo camera. The ground resolution is approximately 16 m/pixel and the images are centred at about 78°N/106°E.

Mars Express is also equipped with the Visual Monitoring Camera that captures daily images of the Red Planet.

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Removing Aeolus’ red tags

When preparing a satellite for launch, the engineers use big red tags to mark components that must be removed before the satellite is encapsulated in the rocket fairing and launched. The idea is to remove these components as late as possible in the launch campaign, and the red tags serve as an important reminder do so. These items are usually covers that protect things like optics, connectors and so on. Very careful attention is paid to removing these items because if one is forgotten, the satellite will not work properly and there’s a good chance that the mission will be lost. The Aeolus launch campaign team in Kourou, French Guiana, has been making sure that the satellite's red tags are removed.

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Aeolus red tags

When preparing a satellite for launch, the engineers use big red tags to mark components that must be removed before the satellite is encapsulated in the rocket fairing and launched. The idea is to remove these components as late as possible in the launch campaign, and the red tags serve as an important reminder do so. These items are usually covers that protect things like optics, connectors and so on. Very careful attention is paid to removing these items because if one is forgotten, the satellite will not work properly and there’s a good chance that the mission will be lost. The Aeolus launch campaign team in Kourou, French Guiana, has been making sure that the satellite's red tags are removed.

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Proba-1 view of Guam

A cloud-specked view of the US territory of Guam in the western Pacific Ocean, as seen by ESA’s Proba-1 microsatellite, which is still observing Earth despite being launched 16 years ago.

Antonio B. Won Pat International Airport is visible just right of centre. To the north is the town of Tamuning and the bluish, coral-rich shores of Tumon Bay, with the capital Hagåtña to the west.

The cubic-metre Proba-1 was the first in ESA’s series of satellites aimed at flight-testing new space technologies. It was launched on 22 October 2001 but is still going strong as the Agency’s longest-serving Earth-observing mission.

Proba-1’s main hyperspectral CHRIS imager acquires 13 square km scenes at 17 m spatial resolution across 18 programmable visible and near-infrared wavelengths. Proba-1 additionally carries a 5 m-resolution black and white camera. The microsatellite’s agile nature means it can image the same scene from a variety of viewing angles.

Onboard innovations include what were then novel gallium-arsenide solar cells, the use of startrackers for gyroless attitude control, one of the first lithium-ion batteries – now the longest such item operating in orbit – and one of ESA’s first ERC32 microprocessors to run Proba-1’s agile computer.

For more background on Proba-1, read this celebration in the ESA Bulletin.

Proba-1 led the way for the Sun-monitoring Proba-2 in 2009, the vegetation-tracking Proba-V in 2013 and the Proba-3 precise formation-flying mission planned for late 2020.

This image was acquired on 22 March 2018.

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Moon, Mars, Station

This image was taken by ESA astronaut Alexander Gerst from the International Space Station on 30 June 2018 when the Moon and Mars were at its closest so far during his six-month Horizons mission.

For illustration purposes, Mars has been highlighted and enlarged twenty times: the ‘Red Planet’ has a radius of 3389 km but at the time was roughly 67 million km from Earth while the Moon has a radius of 1737 km and was at a distance of around 411 000 km.

The distance from Mars to Earth varies as both planets orbit the Sun and it is at its closest in these weeks, appearing brighter than Jupiter in the night sky. The night of 27 July offers another periodic spectacle during the lunar eclipse when Earth casts its shadow over the Moon causing our satellite to appear red.

With careful planning and some luck it should be possible to see the Red Planet and the reddish moon with the International Space Station always flying past from West to East. In mainland Europe the Moon will rise eclipsed and the total eclipse will continue past 23:00 CEST.

The International Space Station, Moon and Mars are the destinations for ESA’s human and robotic exploration strategy, using low-Earth orbit for research and demonstrating technology, developing the Orion service module and elements for a gateway around the Moon and sending robotic probes to Mars, such as the ExoMars rover that will drill down 2 metres into the surface in search for life.

We would love to see any pictures taken showing the Moon, Mars and the International Space Station in one shot – even better if you manage to get all three during the lunar eclipse. Send your images to ESA’s social media channels, as a Facebook message to ESA, with hashtag #youresa on Instagram, or as a reply to the pinned tweet on @esaspaceflight. Provide as much background to how you took the picture as you can. The best three entries will be eligible to win exclusive prizes.  

Alexander took this picture with a 210 mm lens when not working on the dozens of European experiments run on the International Space Station. Flying at 28 800 km/h it only takes 90 minutes to circle Earth, meaning the astronauts on board fly through the night every 45 minutes: coupled with always-clear skies, there are more opportunities for an astronaut to take the perfect picture. 

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Looming iceberg

This satellite image, captured by Sentinel-2A on 9 July 2018, shows a huge iceberg perilously close to the village of Innaarsuit on the west coast of Greenland. If the berg breaks apart, waves resulting from the falling ice could wash away parts of the village.

The 169 residents of Innaarsuit are relatively used to seeing large icebergs floating by, but weighing around 10 million tonnes, this is reported to be the largest in memory. With chunks of ice calving from the iceberg, a number of residents were evacuated amid fears of a bigger break up. The local power plant is also on the coast so waves could also potentially shut down the village’s power supply. However, there are recent reports that strong winds from the south have started to push the berg to the north. The image also shows several other large icebergs in the vicinity.

The Copernicus Sentinel-2 mission is a two-satellite constellation. Each of the two satellites carries an innovative wide swath high-resolution multispectral imager with 13 spectral bands .The combination of high resolution, novel spectral capabilities, a swath width of 290 km and frequent revisit times provides unprecedented views of Earth and the ability to monitor rapidly changing events such as this.

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The legacy of Planck

Operating between 2009 and 2013, ESA’s Planck mission scanned the sky at microwave wavelengths to observe the cosmic microwave background, or CMB, which is the most ancient light emitted in the history of our Universe. Data from Planck have revealed an ‘almost perfect Universe’: the standard model description of a cosmos containing ordinary matter, cold dark matter and dark energy, populated by structures that had been seeded during an early phase of inflationary expansion, is largely correct, but a few details to puzzle over remain. In other words: the best of both worlds.

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Shaking Orion’s solar wings

Testing the solar wings of the European service module that will provide power, water, air and electricity to NASA’s Orion Moon module.

The solar arrays Orion will use to produce electricity are tested at ESA’s technical heart in the Netherlands. Folded for launch, the fragile solar panels need to survive the rumbling into space aboard the most powerful rocket ever built, NASA’s Space Launch System.

Orion’s solar panels will be folded inside the rocket fairing on the first leg of the trip around the Moon. Once released from the rocket they will unfold and rotate towards the Sun to start delivering power.

To make sure the solar panels will work after the intense launch, ESA engineers are putting them through rigorous tests that exceed what they will experience on launch day. This includes vibrating them on a shaking table and placing them in front of enormous speakers that recreate the harsh launch conditions.

Orion will eventually fly beyond the Moon with astronauts, the first time a spacecraft will support humans with European hardware will also be the farthest humans ever travel from Earth. The first mission – without astronauts – is getting ready for launch in 2019.

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Simulation of asteroid spin creating binary asteroids

This simulation  the top view on the left and side view on the right  shows an aggregate (assumed to be the common structure of small asteroids) asteroid that is spun-up due to differential heating, through the so-called 'YORP' effect. The orange particles are those initially at the surface and the white particles are those initially below the surface. While spinning up, the particles that are at mid-latitude move to the equator where the centrifugal force is greatest. When this force exceeds the gravity of the body, these particles escape and can potentially collide together to form a secondary. This mass shedding process turns an initially more or less spheroidal body into what is known as a top shape body, i.e. a spheroid with an equatorial bulge, which seems to be a common shape based on radar models of some small  asteroids, as well as direct images of asteroids Ryugu and Steins (and soon Bennu, the destination of NASA's OSIRIS-REx mission). Taken from Walsh, K.J., Richardson, D.C. & Michel, P. 2008. Rotational break up as the origin of binary asteroids. Nature 454, 188-191.

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