ESA Mars Express Image: Cappuccino swirls at Mars’ south pole

Swirls of chocolate, caramel and cream, this image is definitely one to trigger sweet-toothed cravings.

Smooth cream-coloured plateaus surrounded by cocoa-dusted ridges interspersed with caramel-hued streaks create a scene reminiscent of a cosmic cappuccino.

This picture is, perhaps surprisingly, from ESA’s Mars Express, which has been exploring and imaging the martian surface and atmosphere since 2003.

We may be used to seeing numerous images of red and brown-hued soil and ruddy landscapes peppered with craters, but the Red Planet isn’t always so red.

The bright white region of this image shows the icy cap that covers Mars’ south pole, composed of frozen water and carbon dioxide.

While it looks smooth in this image, at close quarters the cap is a layered mix of peaks, troughs and flat plains, and has been likened in appearance to swiss cheese.

The southern cap reaches some 3 km thick in places, and is around 350 km in diameter. This icy region is permanent; in the martian winter another, thinner ice cap forms over the top of it, stretching further out across the planet and disappearing again when the weather warms up.

The cap is around 150 km north of Mars’ geographical south pole and Mars Express has shed light on why this ice cap is displaced.

Perspective view of Hellespontus Montes

Credit: ESA

Deep impact craters,notably the Hellas Basin, the largest impact structure on the entire planet at 7 km deep and 2300 km across, funnel the strong winds that blow across Mars towards its southern pole, creating a mix of different low- and high-pressure systems.

The carbon dioxide in the polar cap sublimates at different rates in these regions with contrasting pressure, resulting in the cap’s lopsided structure.

Mars Express imaged this area of Mars on 17 December 2012, in infrared, green and blue light, using its High Resolution Stereo Camera.

This image was processed by Bill Dunford, using data available from the ESA Planetary Science Archive.

Mars HiRise Image: UK's ill-fated Mars Probe Beagle 2 may have been spotted

More than 11 years after UK Mars probe Beagle 2 was lost, believed crashed, space scientists are set to reveal new findings about what hapened to the spacecraft.

Mystery surrounds exactly what will be disclosed by experts from the European Space Agency and the underfunded, struggling, UK Space Agency at the English National Academy of Science, known as the Royal Society in London on Friday, but it has raised hopes that orbiting spacecraft around Mars might have located the debris of the Beagle 2.

The probe was the brainchild of the eccentric, mutton-chopped Professor Colin Pillinger, of the UK’s Open University, who died suddenly in May 2014 from a brain haemorrhage.

Beagle 2 was carried to Mars by ESA’s Mars Express which remains in orbit to this day performing valuable surveys of the planet.

Beagle was due to land on Christmas Day 2003, but nothing was ever heard from the tiny craft.

Experts later concluded that its parachute had failed in the extra thin atmosphere and it hit the ground too hard.

Months later, Colin called an impromptu press conference, convinced that he had identified a speck in a photo of the martian surface as his lost probe, but later higher-resolution imagery from a NASA orbiter showed there was nothing.

This recent announcement would indicate that this time there is hope that something really has been spotted.

The panel at Friday’s announcement will include Beagle 2’s mission manager Professor Mark Sims, Dr John Bridges of Leicester University’s Space Research Centre, the European Space Agency’s director of science and robotic exploration Alvaro Giménez, and David Parker, of Durham University and the underfunded UK Space Agency.

A recent image from the HiRise camera on the NASA MRO. 

Credit: NASA, JPL, University of Arizona

All are remaining tight-lipped about what will be revealed, but interestingly, Dr Bridges is a member of the team working with the HiRISE camera aboard NASA's Mars Reconnaissance Orbiter, which is the only imager powerful enough to pick out the debris of Beagle 2, or any other probe, from orbit.

John Zarnecki, Emeritus Professor of Space Science, and Professor Pillinger’s former colleague, told reporters: “I don’t know what they will announce. All one can think of is that they might have got an image of the probe, but if Beagle 2 is in a thousand pieces, it is unlikely that we will have found the pieces.”

“When dear old Colin was alive, he imagined he could see the Beagle 2 in single pixels. None of us could see it, he was the only one who could. So if they really have found it this time, it would be wonderful.”

Professor Zarnecki, who headed the OU’s Planetary and Space Sciences department, said that finding Beagle 2 would be an important event, but there was no chance that it could still work.

He said: “The probe will be dead. There could be no battery life and it would have frozen probably. Electronic materials and components don’t like the cold of Mars very much.”

“The main thing is that it could tell us something about how and why it failed. We’re not going to get anything scientific out of it now, but anything we can learn about how and why it failed informs our designs for the future.

“One of the reasons why space missions on the whole are so successful is that we do learn from experience. It is similar to why flying by plane is so safe - we learn from failures.”

Professor Zarnecki had his own experiment on Beagle 2, a tiny device to measure temperature, air pressure, and wind-speed and direction, “like a weather station, but a fancy one”, he said.

ESA Mars Express: Flying over Becquerel Crater - Video

This latest release from the camera on ESA’s Mars Express is a simulated flight over the Becquerel crater, showing large-scale deposits of sedimentary material.

Becquerel crater is 167 km in diameter and lies in the Arabia Terra region on Mars, on the boundary between the southern highlands and northern lowlands.

This movie shows the location of Becquerel crater on Mars and then provides a flyover of a mound of layered, sulphate-bearing deposits on the crater floor, thought to have formed under the influence of water.

The darker material surrounding the mound is wind-blown dust from a source to the north, and provides evidence for effects of wind in eroding the sedimentary deposits.

The movie was made from a mosaic of four individual images acquired by the High Resolution Stereo Camera on ESA’s Mars Express during orbits 3253/1, 5332, 5350 and 5368.

The image is centred at about 22ºN / 352ºE. The average ground resolution is about 17 m per pixel.

Mars Spacecraft reveal comet flyby effects on Martian atmosphere

Two NASA and one European spacecraft, including NASA's MAVEN mission led by the University of Colorado Boulder, have gathered new information about the basic properties of a wayward comet that buzzed by Mars Oct. 19, directly detecting its effects on the Martian atmosphere.

Data from observations carried out by MAVEN, NASA's Mars Reconnaissance Orbiter (MRO) and the ESA's Mars Express spacecraft revealed that debris from the comet, known officially as Comet C/2013 A1 Siding Spring, caused an intense meteor shower and added a new layer of ions, or charged particles, to the ionosphere.

The ionosphere is an electrically charged region in the atmosphere that reaches from about 75 miles (120 kilometers) to several hundred miles above the Martian surface.

ESA's Mars Express spacecraft

Using the observations, scientists were able to make a direct connection between the input of debris from the meteor shower to the subsequent formation of the transient layer of ions, the first time such an event has been observed on any planet, including Earth, said the MAVEN research team.

The comet traveled from the most distant region of our solar system called the Oort Cloud and made a close approach at 2:27 p.m. EDT within about 87,000 miles (139,500 kilometers) of the Red Planet.

That is less than half the distance between Earth and our moon and less than one-tenth the distance of any known comet flyby of Earth.

"MAVEN is well suited for studying the effects of the dust from the comet in the Martian atmosphere, because it makes measurements at the altitudes where the dust was expected to have an effect," said CU-Boulder Professor Bruce Jakosky of the Laboratory for Atmospheric and Space Physics, the principal investigator on the $671 million Mars Atmosphere and Volatile EvolutioN (MAVEN) mission.

"We also should be able to see if there are long-term effects from the comet dust in that same region of the atmosphere."

The places where the red line on this graph extends higher than the blue line show detection of metals added to the Martian atmosphere from dust particles released by a passing comet. 

The graphed data are from the Imaging Ultraviolet Spectrograph (IUVS) on NASA's MAVEN spacecraft, which recorded the intensities of emission by ingredients in the Martian atmosphere just before (blue line) and after (red line) comet C/2013 A1 Siding Spring sped within about 87,000 miles (139,500 kilometers) of Mars on Oct. 19, 2014. 

The "before" line records the usual main gases in the atmosphere, primarily carbon dioxide and its byproducts.

The "after" line includes those plus peaks at 280 nanometer wavelength, a fingerprint of ionized magnesium, and other wavelengths that are fingerprints of iron.

Researchers interpret this change as a result of vaporisation of dust particles that came from the comet and entered the Martian atmosphere at high speed.

Imaging Ultraviolet Spectrograph (IUVS)

IUVS uses limb scans to map the chemical makeup and vertical structure across Mars' upper atmosphere.

Dust from the comet was vaporized high in the Martian atmosphere, producing what was likely an impressive meteor shower.

The debris resulted in significant but temporary changes to the planet's upper atmosphere and possible longer-term changes.

A host of Earth-based and orbiting telescopes also observed the unique celestial event.

The MAVEN spacecraft, recently arrived at Mars, detected the comet encounter in two ways.

The remote-sensing Imaging Ultraviolet Spectrograph (IUVS) designed and built at CU-Boulder observed intense ultraviolet emissions from magnesium and iron ions high in the atmosphere in the aftermath of the meteor shower.

Not even the most intense meteor storms on Earth have produced as strong a response as this one:

The emission dominated Mars' ultraviolet spectrum for several hours after the encounter and then dissipated over the next two days, according to the MAVEN science team.

MAVEN also was able to directly sample and help scientists determine the composition of some of the vaporised comet dust in Mars' atmosphere.

Analysis of these samples by the spacecraft's Neutral Gas and Ion Mass Spectrometer (NGIMS) designed and developed at NASA Goddard Space Flight Center in Greenbelt, Maryland, detected eight different types of metal ions, including sodium, magnesium and iron.

These are the first direct measurements of the composition of dust from an Oort Cloud comet.

The Oort Cloud, well beyond the outermost planets that surround our sun, is a spherical region of icy objects believed to be material left over from the formation of the solar system.

An illustration of Maven spacecraft at Mars. Credit: NASA

"They call this comet encounter a once-in-a-lifetime event, but it's more like once-in-a-million years," said CU-Boulder Associate Professor Nick Schneider, a LASP research associate and lead IUVS scientist for the mission.

"MAVEN got there just in time, and we were ready.

The numbers suggest a Martian would have seen many thousands of shooting stars per hour, possibly enough to be called a meteor storm, so it must have been a spectacular event that night on Mars."

Elsewhere above Mars, a joint U.S. and Italian instrument on Mars Express observed a huge increase in the density of electrons in the Martian ionosphere following the comet's close approach.

"This historic event allowed us to observe the details of this fast moving Oort Cloud comet in a way never before possible using our existing Mars missions," said Jim Green, director of NASA's Planetary Science Division at the agency's headquarters in Washington.

"Observing the effects on Mars of the comet's dust slamming into the upper atmosphere makes me very happy that we decided to put our spacecraft on the other side of Mars at the peak of the dust tail passage and out of harms way."

There are three CU-Boulder undergraduates and two graduate students on the IUVS science team, said Schneider, and there will be a number of additional CU-Boulder students working on MAVEN in the coming years.

Currently there are more than 100 students working on research projects at LASP, which provides hands-on training for future careers as engineers and scientists.

Comet Siding Spring Buzzes C2013 A1 Mars in Once-in-a-Lifetime Flyby

Credit: SLOOH

Comet Siding Spring C2013 A1 zoomed by Mars today (Oct. 19) in an extremely rare close encounter that scientists billed as a "once-in-a-lifetime" event that may help researchers better understand the earliest days of our solar system.

Comet Siding Spring C2013 A1 came within just 87,000 miles (139,500 kilometers) of the Martian surface at 2:27 p.m. EDT (1827 GMT) today, about one-third of the distance between Earth and the moon.

At the time of closest approach, the comet barreled by at 126,000 mph (203,000 km/h) relative to the Red Planet, NASA officials said.

All seven spacecraft currently operating on or around Mars were scheduled to observe the close shave, with the aim of learning more about comet composition and behaviour.

The US Deep Space Network monitored the NASA Mars satellites currently orbiting Mars.

Credit: SLOOH

NASA's Mars Reconnaissance Orbiter safely watches Comet Siding Spring FlyBy

NASA's Mars Reconnaissance Orbiter, which has sent home more data about Mars than all other missions combined, is also now providing data about a comet that buzzed The Red Planet today (Oct. 19).

The orbiter continues operating in good health after sheltering behind Mars during the half hour when high-velocity dust particles from comet C/2013 A1 Siding Spring had the most chance of reaching the paths of Mars orbiters.

The Comet Siding Spring C/2013 A1 is indicated on this image as it passes Mars, seen here shining brightly on the bottom left.

Credit: Slooh

maintained radio communications with Earth throughout the comet's closest approach, at 11:27 a.m. PDT (2:27 p.m. EDT), and the peak dust-risk period centered about 100 minutes later.

"The spacecraft performed flawlessly throughout the comet flyby," said Mars Reconnaissance Orbiter Project Manager Dan Johnston of NASA's Jet Propulsion Laboratory, Pasadena, California. "It maneuvered for the planned observations of the comet and emerged unscathed."

Following the critical period of dust flux, the orbiter is communicating at 1.5 megabits per second with NASA's Deep Space Network.

It remained on Side A of its two redundant computers, and all subsystems are working as expected.

The remainder of the NASA Mars orbiters, Mars Express and ISRO's MOM, appear to be in good health and unaffected by the comet flyby.

An artist impression of the passing of Comet Siding Spring as seen by Curiosity Rover on Mars.

Credit: SLOOH

ESA Mars Express ready for Comet Siding Spring Encounter - Video update

Europe’s Mars orbiter and its scientific instruments will have a frontrow seat on Sunday when Comet Siding Spring grazes the Red Planet, skimming past at a little more than a third of the Moon’s distance from Earth.

Comet Siding Spring, discovered in January 2013, is less than a kilometre across and will pass Mars at 56 km/s, closing to within 139 500 km at 18:27 GMT (20:27 CEST) on 19 October.



Initially, the comet and its envelope of gas and dust were predicted to pass much closer to Mars, posing a serious risk to the fleet of orbiting spacecraft. Later observations confirmed that the miss distance will, in fact, be more comfortable, around 85,000 miles.

ESA’s teams flying Mars Express have spent months preparing for the encounter.

“In 2013, we had very little information about the comet, which was still very far and faint. In the worst case, we expected the pass to be much closer, and the comet to be much more active,” says Spacecraft Operations Manager Michel Denis.

“We designed a special mode for Mars Express that would minimise any risk due to impacts with cometary particles.

“This included turning off all instruments and non-essential onboard systems, and turning the spacecraft so as to use the large high-gain antenna as a shield.”

ESA's Mars Express Orbiter
currently orbiting Mars.

Credit: ESA

This image shows just how many satellites and probes humanity has sent to Mars. 

Some more successful than others, and we still have much to learn about our near neighbour.

ESA Mars Express: Winter in Hooke crater in Argyre basin

Perspective view of Hooke crater in Argyre basin taken by the High Resolution Stereo Camera (HRSC) on ESA’s Mars Express. 

Credit: ESA /DLR

Over billions of years, the southern uplands of Mars have been pockmarked by numerous impact features, which are often so closely packed that they overlap.

One such feature is Hooke crater, shown in this frost-tinged scene, imaged by ESA’s Mars Express during winter in the southern hemisphere.

Hooke crater. Credit: ESA

Hooke crater is located near the northern edge of the 1800 km-wide Argyre basin, one of the most impressive impact structures on Mars, excavated in a giant collision about 4 billion years ago.

Sitting in a flat part of the basin known as Argyre Planitia, Hooke crater has a diameter of 138 km and a maximum depth of about 2.4 km.

It is named after the English physicist and astronomer Robert Hooke (1635–1703).

Hooke crater comprises two different impact structures, with a smaller impactor blasting a depression off-centre in the floor of a larger, pre-existing crater.

High Resolution Stereo Camera (HRSC)

The newer crater in the centre is filled with a large mound topped by a dark dune field. The mound appears to be composed of layered material, possibly alternating sheets of sand and frost.

Dark dunes also spread southwards (to the left in the topographic, main colour and 3D images) from the smaller crater, partially covering the floor of the main crater.

The local topography modifies the airflow, serving as a sand trap for the wind-blown sediments.

Hooke crater topography. Credit: ESA

In these images, much of the low-lying region to the south, as well as the central mound inside Hooke crater, is covered with a thin, white coating of carbon dioxide frost.

At higher elevations and on north-facing crater walls, the frost is largely absent and appears only in areas shaded from direct sunlight by the walls of smaller craters.

Outside the crater, there are a number of linear features visible on the floor of Argyre Planitia, on the south (left) side of the topographic, main colour and 3D images.

These are examples of ‘yardangs’, rocky ridges that have been shaped by prolonged wind erosion.

Most of the yardangs are oriented towards Hooke crater, indicating the prevailing wind direction.

An artist view of the HRSC on ESA Mars Express scanning the Mars mesas. 

Credit: ESA /DLR

Also visible on the floor of the Argyre basin are small areas of chaotic terrain, which resemble depressions containing flat-topped mesas, buttes and hills.

In the topographic, main colour and 3D images, one of these regions can be seen at the top edge, about a third of the way from the left, and another in the lower middle part, down from the left-most edge of the crater.

Chaotic terrains like these are thought to have been created when large-scale melting of ground ice caused the ground to collapse.

Where the terrain has not collapsed completely, the larger mesas may still contain substantial water ice.

ESA Mars Express HRSC Image: Hellespontus Montes topography image

Credit: ESA

This is a colour-coded topography map of a portion of the western rim of the Hellas basin.

The crater shown in the upper left is on the periphery of this larger impact basin.

The edge of the Hellas basin is traced by a string of rocky peaks known as the Hellespontus Montes, revealed as the red/white ridge in this topography map thanks to their height.

White and red show the highest terrains, while blue and purple show the deepest.

The image is based on a digital terrain model of the region, from which the topography of the landscape has been derived.

The image was created using data acquired with the High Resolution Stereo Camera on ESA’s Mars Express on 13 January 2014 during orbit 12 750. North is to the right, east is up.

New type of dust in Martian atmosphere discovered

A group of French and Russian scientists, including three specialists from Moscow Institute of Physics and Technology, has discovered a new peculiarity of the Martian atmosphere.

The scientists had analyzed satellite-acquired data and concluded that the dust particles in the planet's atmosphere can be of two types.

The scientific article which presents the results of the research in detail has been published in Icarus.

The Russian contributors to the research, Anna Fedorova, Alexander Rodin and Oleg Korablev, are the specialists of MIPT and SRI (IKI) RAS.

These scientists and their French colleagues from the Paris Observatory and LATMOS research laboratory have carried out a simultaneous analysis of the ultraviolet and infrared atmospheric extinctions from SPICAM, the spectrometer on the board of the orbital station Mars Express.

The results were received during the solar occultations at the beginning of Northern summer on Mars.

Before the Sun is completely eclipsed by the planetary disk, its rays pierce through the atmosphere and then get "caught" by the spectrometer's detector.

Having gone through the atmosphere, the solar rays show a different spectrum with the changes hinting at the atmosphere's makeup, the amount of various aerosols and the size of their particles.

This method was applied to understand the way the particles are distributed in the atmosphere.

The researchers have found out that the dust particles in the Martian atmosphere are not homogeneous, but can be roughly grouped into two modes.

• The first – coarser - mode is represented by both H2O ice grains with the average radius of 1.2 μm, and slightly smaller dust particles (R = 0.7 μm).
• The second mode is a lot finer, it is an aerosol which consists of much smaller particles with a radius of 0.04–0.07 μm.

Interestingly, the density number of the both modes is not that high. Even in the most "dusty" layers of the planet's atmosphere at altitudes of 20–30 km there are about 3.000 particles of the finer mode per 1 cm³, and not more than 2 particles of the coarser mode per 1 cm³.

If compared with what is considered the norm on Earth, the air with such dust density is rather clean (rooms are usually a lot dustier); yet, aerosols are important because they, according to the scientists, play a key role in forming the planet's climate.

Because of fine dust particles in the higher layers of the atmosphere, ice "embryos" are formed faster, which, in turn, influences clouds' build-up. The clouds are responsible for both precipitation and temperature condition on the planet's surface.

Analyzing the way the dust is spread in the atmosphere of the planet with regard to the altitude and geographical coordinates is crucial for forming the full picture of what is happening on Mars.

Besides that, the dust modes which the scientists have discovered confirm that Martian dust storms ("dust devils") are able to lift large quantities of substance from the planet's surface.

The researchers point out that the fact of fine dust presence in the atmosphere can contradict the previously obtained data on the existence of the supersaturated steam at the same altitude.

More information: Icarus, www.sciencedirect.com/science/… ii/S0019103513005332

ESA Mars Express: Beauty from chaos - Osuga Valles

Osuga Valles

Beautiful streamlined islands and narrow gorges were carved by fast-flowing water pounding through a small, plateau region near the southeastern margin of the vast Vallis Marineris canyon system.

Images captured on 7 December 2013 by ESA’s Mars Express show the central portion of Osuga Valles, which has a total length of 164 km.

It is some 170 km south of Eos Chaos, which lies in the far eastern section of Valles Marineris.

Osuga Valles is an outflow channel that emanates from a region of chaotic terrain at the edge of Eos Chaos to the west (top in the main images).

Such landscape is dominated by randomly oriented and heavily eroded blocks of terrain.

Another example is seen at the bottom of this scene, filling the 2.5 km-deep depression into which Osuga Valles empties.

Osuga Valles Topography

Catastrophic flooding is thought to have created the heavily eroded Osuga Valles and the features within it.

Streamlines around the islands in the valley indicate that the direction of flow was towards the northeast (bottom right in the main colour, topographic and 3D images shown here) and sets of parallel, narrow grooves on the floor of the channel suggest that the water was fast flowing.

Differences in elevation within the feature, along with the presence and cross-cutting relationships of channels carved onto the islands, suggest that Osuga Valles experienced several episodes of flooding.

The perspective view, which is oriented with the direction of the water flow towards the top of the image, shows the details of the grooved valley floor and the channels carved into the islands more clearly.

Perspective view of Osuga Valles

Close to the northern-most (far right) part of the channel in the main images, two large irregular-shaped blocks appear to have broken away from the surrounding terrain, but do not seem to have experienced as much erosion as the rounded islands.

The floodwater eventually emptied into the deep depression of chaotic terrain at the bottom of the main images, but it is not yet known whether the water drained away into the subsurface or formed a temporary lake.

ESA Mars Express: Lava Flows within Daedalia Planum on Mars

ESA's ESA’s Mars Express reveals two distinct volcanic eruptions have flooded this area of Daedalia Planum on Mars, flowing around an island of ancient terrain. 

The smooth, fractured terrain to the south (left) predates the rough-textured lava flow that dominates the northern (right) side of the image. 

The lava flows arose from the giant Arsia Mons volcano, part of the Tharsis complex around 1000 km to the northwest. 

The blue–grey colour at the bottom left of the image likely reflects a difference in the composition of exposed material: for example, wind-blown ash or dust deposits can easily accumulate in faults or channels. 

The image was created using data acquired on 28 November 2013 during Mars Express orbit 12 593 using the High Resolution Stereo Camera. 

The image resolution is about 14 m per pixel. The image centre is at about 25ºS/249ºE. North is right and east down.

This region of Daedalia Planum includes Mistretta Crater and sits close to the Claritas Fossae region of Mars. 

The giant Tharsis Montes volcanoes lie more than 1000 km to the northwest.

Colour-coded topography map of Daedalia Planum, featuring a segment of highland terrain that is home to Mistretta Crater, the largest of the three eroded impact craters. 

White and red show the highest terrains, while blue and purple show the deepest. 

The image is based on a digital terrain model of the region, from which the topography of the landscape can be derived. 

The region clearly slopes to the south (left). This region was imaged by the high-resolution stereo camera on ESA’s Mars Express on 28 November 2013 (orbit 12 593), with a ground resolution of 14 m per pixel. 

The image centre is at about 25ºS/249ºE. North is right and east down.


Credit: ESA /DLR

Read the full article about Daedalia Planum on ESA Mars express portal. You can also view more ESA Mars express images from Mars here.

ESA Mars Express orbiter reveals overflowing craters

Credit: ESA/DLR/FU Berlin (G. Neukum)

Large and small, hundreds of thousands of craters scar the surface of Mars, hollowed out by a multitude of asteroids and comets that impacted the Red Planet throughout its history.

This image shows a region of the planet's northern hemisphere known as Hephaestus Fossae – after the Greek god of fire – that was imaged by the high-resolution stereo camera on ESA's Mars Express orbiter on 28 December 2007.

The image has been coloured to indicate the elevation of the terrain: green and yellow shades represent shallow ground, while blue and purple stand for deep depressions, down to about 4 km.

Scattered across the scene are a few dozen impact craters that cover a wide range of sizes, with the largest boasting a diameter of around 20 km.

The long and intricate canyon-like features that resemble riverbeds are the phenomenal aftermath of the same fierce impacts that created the largest craters.

When a small body such as a comet or an asteroid crashes at high speed into another object in the Solar System, the collision dramatically heats up the surface at the impact site.

In the case of the large crater seen in this image, the heat produced by such a powerful smash melted the soil – a mixture of rock, dust and also, hidden deep down, water ice – resulting in a massive overflow that flooded the surrounding environment.

Before drying up, this muddy fluid carved a complex pattern of channels while making its way across the planet's surface.

The melted rock–ice mixture also gave rise to the fluidised appearance of the debris blankets surrounding the largest crater.

Based on the lack of similar structures near the small craters in this image, scientists believe that only the most powerful impacts – those responsible for forging the largest craters – were able to dig deep enough to release part of the frozen reservoir of water lying beneath the surface.

ESA Mars Express Image: Juventae Chasma

Intriguing mounds of light-toned layered deposits sit inside Juventae Chasma, surrounded by a bed of soft sand and dust.

The origin of the chasma is linked to faulting associated with volcanic activity more than 3 billion years ago, causing the chasma walls to collapse and slump inwards, as seen in the blocky terrain in the right-hand side of this image.

At the same time, fracturing and faulting allowed subsurface water to spill out and pool in the newly formed chasm. 

Observations by ESA’s Mars Express and NASA’s Mars Reconnaissance Orbiter (MRO) show that the large mounds inside the chasma consist of sulphate-rich materials, an indication that the rocks were indeed altered by water.

The mounds contain numerous layers that were most likely built up as lake-deposits during the Chasma’s wet epoch. 

But ice-laden dust raining out from the atmosphere – a phenomenon observed at the poles of Mars – may also have contributed to the formation of the layers.

While the water has long gone, wind erosion prevails, etching grooves into the exposed surfaces of the mounds and whipping up the surrounding dust into ripples. 

The image was taken by the high-resolution stereo camera on ESA’s Mars Express on 4 November 2013 (orbit 12 508), with a ground resolution of 16 m per pixel. 

Credits: ESA/DLR/FU Berlin (G. Neukum)

ESA Mars Express: Phobos Flyby - Video

On 29 December 2013, ESA's Mars Express will make the closest flyby yet of the Red Planet's moon Phobos, skimming past only 45 km above its surface.

As the spacecraft passes close to Phobos, it will be pulled slightly off course by the moon's gravity, by a few tens of centimetres. 

This small deviation will be measured using the spacecraft's radio signals, and then translated into measurements of gravity, mass and density at different locations on the moon.

ESA Mars Express heading towards daring flyby of Phobos

The High Resolution Stereo Camera (HRSC) onboard the ESA spacecraft Mars Express took this image of Phobos using the HRSC nadir channel on 7 March 2010, HRSC Orbit 7915. 

This image has additionally been enhanced photometrically for better bringing features in the less illuminated part. Resolution: about 4.4 meters per pixel. 

Credit: ESA/DLR/FU Berlin (G. Neukum)

Late this month, ESA's Mars Express will make the closest flyby yet of the Red Planet's largest moon Phobos, skimming past at only 45 km above its surface.

The flyby on 29 December will be so close and fast that Mars Express will not be able to take any images, but instead it will yield the most accurate details yet of the moon's gravitational field and, in turn, provide new details of its internal structure.

As the spacecraft passes close to Phobos, it will be pulled slightly off course by the moon's gravity, changing the spacecraft's velocity by no more than a few centimetres per second.

These small deviations will be reflected in the spacecraft's radio signals as they are beamed back to Earth, and scientists can then translate them into measurements of the mass and density structure inside the moon.

Earlier flybys, including the previous closest approach of 67 km in March 2010, have already suggested that the moon could be between a quarter and a third empty space – essentially a rubble pile with large spaces between the rocky blocks that make up the moon's interior.

Knowing the structure of the roughly 27 x 22 x 18 km Phobos will help to solve a big mystery concerning its origin and that of its more distant sibling, Deimos, which orbits Mars at approximately three times greater distance.

The leading theories propose that the duo are either asteroids captured by Mars, or that they were born from debris thrown up from giant impacts on Mars.

The innermost moon of Mars, Phobos, is seen here in full 360 degree glory. 

The images were taken by the High Resolution Stereo Camera (HRSC) on ESA’s Mars Express at various times throughout the mission’s 10 years. 

The moon’s parallel sets of grooves are perhaps the most striking feature, along with the giant 9 km-wide Stickney impact crater that dominates one face of the 27 x 22 x 18 km moon. 

The origin of the moon’s grooves is a subject of much debate.

One idea assumes that the crater chains are associated with impact events on the moon itself. 

Another idea suggests they result from Phobos moving through streams of debris thrown up from impacts 6000 km away on the surface of Mars, with each ‘family’ of grooves corresponding to a different impact event.

Mars Express has imaged Phobos from a wide range of distances, but will make its closest flyby yet on 29 December 2013, at just 45 km above the moon. 

Although this is too close to take images, gravity experiments will give insight into the interior structure of Phobos. 

Credit: ESA / DLR / FU Berlin (G. Neukum)

"By making close flybys of Phobos with Mars Express in this way, we can help to put constraints on the origin of these mysterious moons," says Olivier Witasse, ESA's Mars Express project scientist.

In addition to probing the gravitational field of Phobos during its close approach, Mars Express will be making measurements of how the solar wind influences the moon's surface.

"At just 45 km from the surface, our spacecraft is passing almost within touching distance of Phobos," says Michel Denis, Mars Express Operations Manager.

"We've been carrying out manoeuvres every few months to put the spacecraft on track and, together with the ground stations that will be monitoring it on its close approach, we are ready to make some extremely accurate measurements at Phobos."

ESA MARS Express: MARS North Pole Fly-by - Video

Data from the Mars Advanced Radar for Subsurface and Ionospheric Sounding instrument, MARSIS aboard ESA's Mars Express has been used to create this animation of the Red Planets north pole. The ice cap is about 1000km in diameter (621 miles).

Credit: ESA

ESA Mars Express: Mars Ice Cap and Chasma Boreale - Video

Enjoy views of the martian north pole from all angles in this new animation from ESA’s Mars Express.

The ice cap has a diameter of about 1000 km and consists of many thin layers of ice mixed with dust that extend to a depth of around 2 km below the cap.

The prominent gap in the ice cap is a 318 km-long, 2 km-deep chasm called Chasma Boreale.

The layers result from variations in the orbit and rotation of Mars that affect the amount of sunlight received at the poles, and thus the amount of melting and deposition of materials over time.

Meanwhile, strong prevailing winds are thought to be responsible for shaping the spiral troughs.

The polar ice cap in this movie was constructed using data provided by the Mars Advanced Radar for Subsurface and Ionospheric Sounding instrument, MARSIS.

Low-frequency radio waves beamed towards the surface are reflected back to Mars Express from the planet’s surface and from interfaces between layers of different materials underground.

The strength and timing of the radar echoes are a gauge of the depths of different types of interfaces, such as between rock, water or ice. This information can then be translated into 3D views, as seen in this movie.

ESA's Mars Express: Huge Martian Landforms Detail Revealed

ESA's Mars Express orbited the Red Planet nearly 12,500 times by October 2013. Its high resolution stereo camera images, assembled in this "fly-around," show riverbeds, volcanoes, canyons and craters.

Credit: ESA / DLR / FU Berlin (G. Neukum)

ESA Mars Express Image: Hebes Chasma

This mosaic of Hebes Chasma on Mars is composed of eight single images taken with the High Resolution Stereo Camera on Mars Express between 2004 and 2009. 

Hebes Chasma is an enclosed, almost 8 km-deep trough stretching 315 km in an east–west direction and 125 km from north to south at its widest point.


Hebes Chasma is an enclosed, almost 8 km-deep trough stretching 315 km in an east–west direction and 125 km from north to south at its widest point. It sits about 300 km north of the vast Valles Marineris canyon complex.

The origin of Hebes Chasma and neighbouring canyons is associated with the nearby volcanic Tharsis Region, home to the largest volcano in the Solar System, Olympus Mons.

As the Tharsis bulge swelled with magma during the planet’s first billion years, the surrounding crust was stretched, eventually ripping apart and collapsing into gigantic troughs, including Hebes Chasma.

Intricate fault patterns can be seen all around the deep depression – they are especially evident in the main colour and 3D images.

In the centre of Hebes Chasma, there is a flat-topped ‘mesa’ that rises to level similar to that of the surrounding plains.

It is shown from different angles in the two perspective images below.

No other canyon on Mars has a similar feature and its origin is not entirely clear. Its layers include volcanic materials – just like in the main canyon walls – but also wind-blow dust and lake sediments that were laid down over time.

A horseshoe-shaped chunk has been taken out of one side of the mesa, seen below, where material has slumped down onto the valley floor below.

A landslide may also be responsible for the dark patch in this image, which appears to pool like spilt ink across the debris.

It is most likely loose dust that has slid down the walls, perhaps helped along where melting ice or ground-water weakened the rocks to create a flow-like feature.

A similar feature is visible at the opposite end of the mound, as seen in the full-colour image.

Other landslide deposits are seen all over the floor of Hebes Chasma, many coming from the main canyon walls.

Numerous grooves are etched into both the canyon walls and the mesa, suggesting the material is weak and easily eroded.

In the second perspective view above, a thin band of darker material is seen between two layers of light material.

One idea is that the material was blown or slid from the top of the mound and collected on the slopes below.

Dark material is also seen around the base of the mesa, which either eroded away from the younger sediment layers located higher up in the mesa, or were deposited separately by wind or water.
Read more at the ESA Mars Express portal