Tag: MSL

Space Sunday: of water, Apollo and space spies

Posted on by Inara Pey

CuriosityThe Curiosity rover team have released a further study showing that ancient Mars was capable of storing water in lakes over an extended period of time, and that this water was a principal component in the creation of “Mount Sharp”, the mound at the centre of Gale Crater, currently being investigated by the NASA rover.

This forms the latest in a series of reports on the subject of water on Mars and in Gale Crater to be published by the Curiosity science team, and comes almost a year after I wrote about studies released by the team which detailed how “Mount Sharp” – more formally known as Aeolis Mons – was most likely formed by sediments laid down  by successive wet period in Mars’ ancient past.

“Observations from the rover suggest that a series of long-lived streams and lakes existed at some point between about 3.8 to 3.3 billion years ago, delivering sediment that slowly built up the lower layers of Mount Sharp,” said Ashwin Vasavada, Mars Science Laboratory project scientist, discussing the new report.

In December 2014, NASA issued a report on how
In December 2014, NASA issued a report on how “Mount Sharp” was likely formed. On the left, the repeated depositing of alluvial and wind-blown matter (light brown) around a series of central lakes which formed in Gale Crater, where material was deposited by water and more heavily compressed due the weight of successive lakes (dark brown). On the right, once the water had fully receded / vanished from the crater, wind action took hold, eroding the original alluvial / windblown deposits around the “dry” perimeter of the crater more rapidly than the densely compacted mudstone layers of the successive lake beds, thus forming “Mount Sharp”

However, until Curiosity actually started studying “Mount Sharp” in detail,  the accuracy of the earlier studies couldn’t be completely verified. The latest results from the rover indicate that these wetter scenarios were correct for the lower portions of Mount Sharp, and that the filling of at least the bottom layers of the mountain occurred over a period of less than 500 million years, mostly as a result of material deposited by ancient rivers and lakes.

The new report also comes on top of confirmation that the recurring slope lineae (RSL) features seen on Mars from orbit are most likely the result of outflows of water which are occurring today. together they are reshaping some of the thinking around water on Mars – and what might have happened to it.

“What we thought we knew about water on Mars is constantly being put to the test,” said Michael Meyer, lead scientist for NASA’s Mars Exploration Programme. “It’s clear that the Mars of billions of years ago more closely resembled Earth than it does today. Our challenge is to figure out how this more clement Mars was even possible, and what happened to that wetter Mars.”

Strata at the base of
Curiosity has found plenty of evidence for water on the floor of Gale Crater, which likely took the form of one or more lakes during the wetter parts of Mars’ history, before becoming rivers and streams later. Strata at the foot of “mount Sharp” (shown above) strongly suggested water played a significant part in forming the mound, and the evidence for this being the case has continued to be revealed as the rover climbs the lower slopes

Currently, images of the flanks of the mound returned by the rover and from orbit suggest water-transported sedimentary deposition may have extended at least 150 to 200 metres (500 to 650 feet) above the crater floor, and possibly as high as 800 metres (approx 1/2 a mile). This both indicates that there was at least one standing body of water in the crater and further confirms that “Mount Sharp” was a direct result of sediments deposited by this water. Or at least, the lower slopes were; there is currently little evidence for the sedimentary strata extending about the 800 metre mark, however. This has led to speculation that wind-blown deposits are responsible for the upper reaches of the mound.

Taken together, the recent findings concerning Mars and its water suggest that the planet’s history is far more complex than had been thought. “We have tended to think of Mars as being simple,” John Grotzinger, the former project scientist for the Curiosity mission said of the latest findings.

“We once thought of the Earth as being simple too,” he continued. “But the more you look into it, questions come up because you’re beginning to fathom the real complexity of what we see on Mars. This is a good time to go back to re-evaluate all our assumptions. Something is missing somewhere.”

Pluto’s Water

The blue haze of Pluto's atmosphere
The blue haze of Pluto’s atmosphere: released on October 8th, this true colour image taken after the New Horizons spacecraft had completed its closest approach to the dwarf planet shows Pluto’s night side ringed by the blue haze of its thin atmosphere, as illuminated by the distant Sun, far away on the other side of the little world

The latest images and data to be received on Earth from NASA’s New Horizons space vehicle reveal Pluto’s atmosphere to be a rich blue in colour, and confirm that water ice exists on theplanet.

“Who would have expected a blue sky in the Kuiper Belt? It’s gorgeous,” said Alan Stern, New Horizons principal investigator as the striking image shown above was released as part of the latest batch of pictures and data to be received from the space craft and undergo processing and initial analysis.

The blue colour indicates that the haze within Pluto’s atmosphere is made up of a lot very fine of particulate matter, which scatters blue light from the Sun more easily than other colours, due to blue having a shorter wavelength (which is also the reason the sky we see here on Earth also appears blue, because that wavelength is easily scattered by the tiny particles making up our atmosphere).

In Pluto’s case, it’s thought that the particles in the atmosphere are largely tholins, created by ultraviolet radiation from the Sun breaking down the methane and nitrogen in Pluto’s upper atmosphere, allowing their molecules to gradually recombine into the more complex tholins, which draft down through the atmosphere, undergoing further changes, before eventually reaching the surface of the planet, giving it a distinctive reddish colour.

Instruments forming the Ralph suite aboard New Horizons have identified regions of exposed water ice on Pluto which occur in regions which have corresponding deposits of tholins. Quite what the relationship is between the two is unclear. The water ice deposits are shown in blue on the inset image simply for convience, and not because that's how they appear on Pluto
Instruments forming the Ralph suite aboard New Horizons have identified regions of exposed water ice on Pluto which occur in regions which have corresponding deposits of tholins. Quite what the relationship is between the two is unclear. The water ice deposits are shown in blue on the inset image simply for convenience, and not because that’s how they appear on Pluto

The discovery of water ice on Pluto has taken scientists by surprise. Not so much because it is there, but because it appears to be somehow related to areas of heavy tholin deposits. Confirmation of the presence of water ice came from data returned by the Ralph instrument suite aboard New Horizons, but just how widespread it might be isn’t clear, as it seems that it might be masked elsewhere by other surface material.

Continue reading “Space Sunday: of water, Apollo and space spies” →

Space Sunday: of Martian water, avalanches and postcards

Posted on by Inara Pey
A false-colour image of Hale Crater on Mars showing recurring slope lineae (RSL) flowing downhill, which are inferred to have been caused by contemporary flowing water, hydrated salts detected within the dark-colours RSLs tending to confirm they hypothesis they were created by free-flowing water.
A false-colour image of Hale Crater on Mars showing recurring slope lineae (RSL) features flowing downhill. Hydrated salts detected within the dark-coloured RSLs tend to confirm the hypothesis they were, and are, created by free-flowing water.

On Monday, September 28th, NASA held a special press conference which, they had promised, would “solve” a “major” mystery about Mars.

As I noted in my Space Sunday update prior to the conference, the major speculation was that the US space agency would be discussing what are called recurring slope lineae (RSL) features on Mars.

RSLs have been the subject of intense debate and discussion since 2011, when an undergraduate called Lujendra Ojha published the first in a series of papers on their presence on Mars.  In essence, they are ridges and rills which appear on the slopes of hills and craters, notably in the equatorial regions of Mars. The significance here being that on Earth, identical features are always the result of free-flowing water.

Given that it is known that Mars once supported liquid water on its surface, the presence of these features wouldn’t be that exceptional were they part of the ancient landscape. However, as the “recurring” in the title suggests, the Martian RSLs appear to be active – recurring frequently, sometimes on the seasonal basis. renewing and growing, with new ones also being periodically created.

Two images studied by Ojha showing the flank of the same crater and showing what appear to be active RSLs.
Two images studied by Ojha showing the flank of the same crater. On the left, from 2007, a number of older RSLs, faded due to dust deposits, appear with a relatively new, dark RSL. By 2012 (on the right), that RSL feature has also faded, but a further new one has appeared

Given the overall similarities between RSLs seen on Mars and those seen on Earth, particularly in Antarctica, the common belief has been that liquid water is responsible for the features on Mars. If true, then it would indicate two things.

The first would be that Mars would appear to have a subsurface water table of some description – which would be consistent with the idea that as the planet lost its atmosphere, whatever water remained on the surface may have retreated underground. The second is that it would seem to indicate that Mars is still in some way geologically active, with some mechanism at work forcing this water to the surface and creating these sudden, if short-lived outflows.

The NASA conference coincided with the publication of another paper in Nature Geoscience by Ojha and his colleagues. both pointed directly to water being the cause of the Martian RSLs. In particular, they both report that spectral analysis of some of the more recent and broader RSL channels shows they are rich in hydrated salts, which strongly indicates the presence of water. These salts are consistent with the chemical signatures of magnesium perchlorate, magnesium chlorate and sodium perchlorate.

This is significant because the presence of perchlorate deposits in water can work to prevent that water freezing solid in the kind of summer daytime temperatures – around -23C (-10F) – often experienced in the regions where these RSLs are found. Thus, if held in suspension, they would create a watery brine capable for fluid motion, and which, if released in significant enough amounts, could give rise to the RSLs prior to the water itself sublimating rapidly into the tenuous Martian atmosphere, leaving the hydrated deposits behind.

Nepalese born
Nepalese born Lujendra Ojha is the student who started the investigations into RSLs and their possible relation to free-flowing liquid water on Mars (image: The Himalayan)

The conclusion is that it is indeed liquid water that is causing these RSLs on Mars, and that this water is in a liquid, rather than solid state, at least during certain periods, such that it can be forced to the surface.

However, all is still not entirely clear – something which tends to cast a shadow on the idea of a “mystery” having been “solved”. For one thing, if the RSL rills are below a certain width, they are entirely devoid of any hydrated deposits. This could mean that some other process is involved in their formation, which has yet to be determined. Further, the mechanism which is actually responsible for forcing the water to the surface a creating the outflow which result in these RSLs is still unknown.

Continue reading “Space Sunday: of Martian water, avalanches and postcards” →

Space Sunday: of selfies, sprites, and black holes

Posted on by Inara Pey

CuriosityCuriosity, NASA’s Mars Science Laboratory rover has departed “Marias Pass”, a geological contact zone between different rock types on the slopes of “Mount Sharp”, some of which yielded unexpectedly high silica and hydrogen content.

As noted in a recent space update in these pages, silica  is primarily of interest to scientists, because high levels of it within rocks could indicate ideal conditions for preserving ancient organic material, if present. However, as also previously noted, it may also indicate that Mars may have had a continental crust similar to that found on Earth, potentially signifying the geological history of the two worlds was closer than previously understood. Hydrogen is of interest to scientists as it indicates water bound to minerals in the ground, further pointing to Gale Crater having once been flooded, and “Mount Sharp” itself the result of ancient water-borne sediments being laid down over repeated wet periods in the planet’s ancient past.

Curiosity actually departed “Marias Pass” on August 12th, after spending a number of weeks examining the area, including a successful drilling and sample-gathering operation at a rock dubbed “Buckskin”, where the rover also paused to take a “selfie”, which NASA released on August 19th. It is now continuing its steady climb up the slopes of “Mount Sharp.”

A low-angle self-portrait produced from multiple images captured by the Mars Hand Lens Imager (MAHLI) camera mounted on the "turret" at the end of the rover's robot arm. The images were taken on August 5th, as the rover was parked at the "Buckskin" rock formation from which it gathered drill samples
A low-angle self-portrait produced from multiple images captured by the Mars Hand Lens Imager (MAHLI) camera mounted on the “turret” at the end of the rover’s robot arm. The images were taken on August 5th, as the rover was parked at the “Buckskin” rock formation from which it gathered drill samples

As it does so, initial analysis of the first of the samples gathered from “Buckskin” is under-way. It is hoped with will help explain why the “Marias Pass” area seems to have far higher deposits of hydrogen bound in its rocks than have previously been recorded during the rover’s travels. This data has been supplied by the Dynamic Albedo of Neutrons (DAN) instrument on Curiosity, which almost continuously scans the ground over which the rover is passing to gain a chemical signature of what lies beneath it.

“The ground about 1 metre beneath the rover in this area holds three or four times as much water as the ground anywhere else Curiosity has driven during its three years on Mars,” said DAN Principal Investigator Igor Mitrofanov of Space Research Institute, Moscow, when discussing the “Marias Pass” DAN findings. Quite why this should be isn’t fully understood – hence the interest in what the drill samples undergoing analysis might reveal.

A stunning vista: the slopes of "Mount Sharp" as seen by Curiosity as it commenced the upward drive away from "Marias Pass". Captured by the rover's Mastcam systems, the image shows an intriguing landscape, with the gravel and sand ripples typical of much of the terrain over which the rover has passed in the foreground. In the middle distance sit outcrops of smooth, dust-covered bedrock, above which sit sandstone ridges. On the horizon sit rounded buttes, rich in sulfate minerals, suggesting a change in the availability of water when they formed - click image for the full size version
A stunning vista: the slopes of “Mount Sharp” as seen by Curiosity as it commenced the upward drive away from “Marias Pass”. Captured by the rover’s Mastcam systems, the image shows an intriguing landscape, with the gravel and sand ripples typical of much of the terrain over which the rover has passed in the foreground. In the middle distance sit outcrops of smooth, dust-covered bedrock, above which sit sandstone ridges. On the horizon sit rounded buttes, rich in sulfate minerals, suggesting a change in the availability of water when they formed – click image for the full size version

The drilling operation itself marked the first time use of the system since a series of transient short circuits occurred in the hammer / vibration mechanism in February 2015. While no clear-cut cause for the shorts was identified, new fault protection routines were uploaded to the rover in the hope that should similar shorts occur in the future, they will not threaten any of Curiosity’s systems.

A Flight over Mars

With all the attention Curiosity gets, it is sometimes easy to forget there are other vehicles in operation on and around Mars which are also returning incredible images and amounts of data as well – and were doing so long before Curiosity arrived.

One of these is Europe’s Mars Express, the capabilities of which come close to matching those of NASA’s Mars Reconnaissance Orbiter. Mars Express has been in operation around Mars for over a decade, and in that time has collected an incredible amount of data.

At the start of August, ESA released a video made of high resolution images captured by the orbiter of the Atlantis Choas region of Mars. This is an area about 170 kilometres long and 145 wide (roughly 106 x 91 miles) comprising multiple terrain types and impact craters, thought to be the eroded remnants of a once continuous ancient plateau. While the vertical elevations and depressions have been exaggerated (a process which helps scientists to better understand surface features when imaged at different angles from orbit), the video does much to reveal the “magnificent desolation” that is the beauty of Mars.

Continue reading “Space Sunday: of selfies, sprites, and black holes” →

Space Sunday: active Ceres, open Mars, and shooting stars

Posted on by Inara Pey

Dawn mission patch (NASA / JPL)Dawn, the NASA / ESA joint mission to explore two of the solar system’s three “protoplanets” located in the asteroid belt between the orbits of Mars and Jupiter, continues to intrigue scientists as it studies Ceres, the second of its primary targets.

As I reported in June 2015, Dawn is part of a broader effort to better understand the origins of the solar system and how the planets actually formed; all of which might give us greater understanding of how life arose here on Earth.

Launched in September 2007, Dawn arrived at Ceres in March 2015, after a 2.5 year transit flight from Vesta, its first destination, which it had been studying for 14 months following its arrival in July 2011. Because of their relative size – Ceres accounts for around one-third of the total mass of the asteroid belt – both of these airless, rocky bodies are regarded as dwarf planets, rather than “simple” asteroids. However, Ceres is proving to be quite the conundrum.

At the start of July, Dawn completed the first part of its high-altitude survey of Ceres and fired its low-thrust ion drive to start a series of gentle manoeuvres to reduce its orbit around from 4,400 kilometres (2,700 miles) to 1,450 kilometres (900 miles). It’s now hoped that from this lower orbit, the space craft will be able to discover more about some of Ceres’ more mysterious features.

One in particular has been the subject of much debate. It started when Dawn imaged a series of bright spots within the crater Occator as it made its initial loop around Ceres to enter orbit. Since that time, it has repeatedly images the bright spots, and their presence has also been confirmed by the Hubble Space Telescope.

A June 6th image of the bright spots within a crater on Ceres, captured by Dawn on June 6th, 2015, from a distance of
A Dawn spacecraft image of the bright spots within a crater on Ceres, captured on June 6th, 2015. With the vehicle now entering a much lower altitude mapping mission, it is hoped that even more detail on the spots  – and the faint haze discovered within the crater – will be obtained

Currently, it is believed the bright marks might either be salt deposits or water ice (the European  Herschel Space Observatory had previously found evidence of water vapour on Ceres).  However, while the science team aren’t leaning either way, their mission briefing on July 21st, leant some weight to the bright spots perhaps being water ice. This came in the form of an announcement that he 92 kilometre (57 mile) wide Occator has its own, very localised atmosphere focused around the bright areas.

The evidence for this comes from images of the crater taken from certain angles which reveal a thin haze covering around half of the cater, but not extending beyond its walls. Th thinking is that this haze is perhaps the result of the ice in the bright area – if they are ice – sublimating out.

However, if this is the case, it actually raises a further mystery: why the haze? Generally, such sublimation would lead to the resulting gases dissipating very quickly, without forming a haze. One hypothesis is that Ceres’ gravity, which is somewhat higher than might be expected for a body of its size) may be and influencing factor.

The 5 km high "pyramid" mountain pokes up above the limb of Ceres. Flat-topped, it has streaks of bight mateiral on its flanks giving the impression something has been flowing down it.
The 5 km high “pyramid” mountain pokes up above the limb of Ceres. Flat-topped, it has streaks of bright material on its flanks giving the impression something has been flowing down it.

The bright spots aren’t the only curious feature on Ceres. Dawn has also spotted numerous long, linear features whose cause is unknown, as well as one big mountain that mission team members have dubbed “The Pyramid.” This massif, about 5 km (3 mi) in height, and around 30 km (19 mi) across at its base, is oddly flat-topped and has streaks of bright material on one of it flanks, as if something has been cascading down the slope. What this might indicate has planetary scientists scratching their heads at this point.

With all the mysteries thrown up by New Horizon’s recently flyby of Pluto, and Dawn’s discovery of mysterious features on Ceres, it really is becoming a case that the tiny worlds of our solar system are perhaps the most perplexing.

Three years ago, in August 2012, NASA’s Mars Science Laboratory rover, Curiosity, arrived in Gale Crater, Mars. Since that time, the rover has made some remarkable discoveries, as reported in this blog over the years.

To mark the anniversary of the landing, NASA has launched two new on-line tools designed to open the mysterious terrain of the Red Planet to anyone with an interest in planetary exploration.

Experience Curiosity allows users to journey along with the one-tonne rover on its Martian expeditions. The program simulates Mars in 3-D, using actual data returned by the rover and NASA’s Mars Reconnaissance Orbiter (MRO). It also uses a  game-ready rover model based entirely on real mechanisms.

Experience Curiosity allows you to learn about the rover using a 3D model which can be manipulated and driven, using a WebGL application
Experience Curiosity allows you to learn about the rover using a 3D model which can be manipulated and driven, using a WebGL application

User are able to drive the rover, examine it, call up data on key components, witness the driving view from different cameras on the rover, and operated the robot arm. Activities are a little basic, but as this appears to be a part of NASA’s Eyes On project, capabilities may grow over time.

Mars Trek is a much more expansive tool – one which is actually being used in the planning for the Mars 2020 rover mission. It features interactive maps, which include the ability to overlay a range of data sets generated from instruments aboard spacecraft orbiting Mars, and analysis tools for measuring surface features. Standard keyboard gaming controls are used to manoeuvre the user across Mars’ surface, and topographic data can be exported to 3D printers to allow the printing of physical models of surface features.

The map view and be manipulated in 2D or 3D, data on various surface missions is provided, compete with the ability to zoom into the surface locations for these missions, making for a visually impressive model.

Continue reading “Space Sunday: active Ceres, open Mars, and shooting stars” →

Space Sunday: Mars rocks, Ceres glitters, Pluto beckons

Posted on by Inara Pey

CuriosityOperations on and around Mars are resuming following the June 2015 conjunction, which saw Mars and Earth on opposite sides of the Sun, a time which makes reliable two-way communications hard-to-impossible due to the Sun’s interference, so vehicles operating on and around the Red Planet are placed in autonomous modes of relatively safe operations.

For the NASA rovers, Opportunity and Curiosity, this meant parking and waiting for reliable communications to be restored. However, now that Mars has once again emerged from “behind” the Sun, Curiosity is preparing to study the confluence of at least two different types of rock formation on the slopes of “Mount Sharp”.

As noted in my recent Curiosity updates, the Mars Science Laboratory (MSL) had been attempting to reach such a confluence, dubbed “Logan Pass”, but the terrain leading to that location proved more difficult from had been hoped. As a result, the rover was redirected towards another point leading up to higher elevations dubbed “Marias Pass”, and a small valley where the rock formations meet.

A mosaic showing the contact layers near the location dubbed “Marias Pass” on “Mount Sharp”. In the foreground is pale mudstome, similar to that studied by Curiosity at “Pahrump Hills” in 2014. Overlaying this stratigraphically is sandstone that the rover team calls the “Stimson unit.” The images used in this mosaic were captured by Curiosity’s left Mastcam on May 25th, 2015 (Sol 995 of the rover’s surface mission). The colour has been approximately white-balanced to resemble how the scene would appear under daytime lighting conditions on Earth.

The two types of rock are a pale mudstone, similar in appearance to the bedrock studied at “Pahump Hills”; the other is a darker, finely bedded sandstone sitting above the Pahrump-like mudstone, which has been dubbed the “Stimson unit”. In addition, the valley also has a sandstone with grains of differing shapes and colour which the science team wish to examine in more detail as well, having already identified a potential target within it they’ve named “Big Arm”.

“On Mars as on Earth, each layer of a sedimentary rock tells a story about the environment in which it was formed and modified,” NASA spokesman Guy Webster said during a status update on the mission which explained the science team’s interest in the area. “Contacts between adjacent layers hold particular interest as sites where changes in environmental conditions may be studied. Some contacts show smooth transitions; others are abrupt.”

Curiosity is expected to spend the next few weeks examining the rock formations before resuming its trek up the side of “Mount Sharp”.

Dawn Over Ceres

Dawn mission patch (NASA / JPL)
Dawn mission patch (NASA / JPL)

On Monday, June 30th, The joint ESA / NASA Dawn deep space mission completed the second of its orbital mapping phases of Ceres, which it has been carrying out since May at a distance of some 4,400 kilometres (2,700 miles).

During July, the spacecraft will engage in a series of gentle manoeuvres that will allow it to reduce its orbit to 1,450 kilometres (900 miles), ready to start a further surface mapping and investigation mission in early August.

Ceres has revealed it has a much more varied landscape that Vesta, its slightly smaller “sister” protoplanet, which the Dawn spacecraft studied over a prior if 14 months in 2011/12, prior to reaching Ceres in March 2015. One particular point of interest on the latter is a grouping of bright surface features located within a crater some 90 kilometres (55 miles) across.

The most recent images returned be Dawn of these spots reveals they are more numerous than had first been thought, with the largest approximately 9 km (6 miles) across.  It is believed these bright spots are the result of ice or salt, although other causes may be possible; spectra of the region should reveal far more as the spacecraft reduces its orbit.

A closer view of the bright areas inside a crater on Ceres, captured by the European imaging systems aboard the Dawn mission on June 9th, 2015 (credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA)
A closer view of the bright areas inside a crater on Ceres, captured by the European imaging systems aboard the Dawn mission on June 9th, 2015 (credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA)

In addition to the bright spots, the latest images also show a pyramid-like mountain with steep slopes rising to a height of about 5 km (3 miles) from a relatively flat area on Ceres, which has also provoked scientific interest. Ceres is also richly cratered, like Vesta; however, unlike Vesta, many more of the craters on Ceres have central peaks associated with them, evidence of their formation being the result of surface impacts. Images have also revealed evidence of other activities on the rocky, barren surface: slumps, landslides and lava-like flows, all indicative of Ceres perhaps having been somewhat more active in its formative years than Vesta.

Continue reading “Space Sunday: Mars rocks, Ceres glitters, Pluto beckons” →

Space Sunday: conjunctions, volcanoes and space stations

Posted on by Inara Pey
Solar conjunction: when Earth (r) is on the opposite side of the Sun or another solar system body - in this case, Mars (l)
Solar conjunction: when Earth (r) is on the opposite side of the Sun or another solar system body – in this case, Mars (l)

Solar Conjunction

June sees Mars an Earth move into a period of solar conjunction, when they are one opposite sides of the Sun relative to one another. These periods of conjunction occur roughly every 26 months (the last having been April 2013), can see communications between Earth and vehicles operating on and around Mars severely disrupted due to interference from the Sun.

To prevent spacecraft at Mars from receiving garbled commands that could be misinterpreted or even harmful, the operators of Mars orbiters and rovers temporarily stop sending any commands. At the same time, communications from the craft to Earth are also stepped down, and science operations scaled back. Nasa started to do this on Sunday, June 7th, and both ESA and the Indian Space Research Organisation will be doing the same. For the two Mars rovers, Opportunity and Curiosity, it means parking up and no driving until after full communications are restored. General science observation will, however, continue.

One slight difference in all this will be with NASA’s newest orbiter at Mars: MAVEN (Mars Atmosphere and Volatile Evolution). This arrived over Mars in September 2014,  with the primary mission of determining the history of the loss of atmospheric gases to space and gain insight into Martian climate evolution. As such, MAVEN will continue monitoring the solar wind reaching Mars and making other measurements. The reading will be stored within the orbiter’s memory system and transmitted back to Earth once normal communications have been restored.

MOM Studies Mars’ Volcanoes

Mars: The north polar ice cap, the three massive craters of the Tharsis volcanoes forming a diagonal line in the centre, the mighty "boil" of Olympus mons to their left and the 5,000 km long Vallis Marineris to their right
Mars: The north polar ice cap, the three massive craters of the Tharsis volcanoes forming a near-vertical line in the centre, the mighty “boil” of Olympus Mons to their left and the 5,000 km long Vallis Marineris to their right (image courtesy of ISRO)

Another mission that hasn’t gained much attention since also arriving in orbit around Mars is India’s Mangalyaan (“Mars-craft”) vehicle, which reached Mars on September 24th, 2014. Referred to simply as the Mars Oribiter Mission (MOM) by most, the vehicle reached Mars just 2 days after NASA’s MAVEN orbiter, and like that craft, a part of its mission is focused on studying the Martian atmosphere.

MOM also carries a high-resolution surface imaging camera, and this has been busy returning some magnificent picture of Mars, including the brilliant picture of the planet reproduced above, which shows the north polar ice cap, the almost vertical line of the three massive Tharsis Bulge volcanoes of Ascraeus Mons, Pavonis Mons and Arsia Mons in the centre, the massive rise of Olympus Mons, the largest volcano in the solar system to their left, and the 5,000 kilometre scar of the massive Vallis Marineris to their right.

MOM’s camera is also capable of producing 3D images, and an example of this capability was released by ISRO on June 5th in the form of a dazzling image of Arsia Mons, the southernmost of the equator spanning Tharsis volcanoes. The image was actually captured on April 1st, 2015, and has a spatial resolution of 556 metres, and the camera some 10,707 kilometres from the surface of Mars when the picture was taken.

The mighty Arsia Mons on Mars, largest of the three Tharsis Bulge volcanoes. The image shows a deliberate vertical exaggeration to the volcano's slope
The mighty Arsia Mons on Mars, largest of the three Tharsis Bulge volcanoes. The image shows a deliberate vertical exaggeration to the volcano’s slope (image courtesy of ISRO)

To give some idea of the scale of this massive shield volcano, it is 435 kilometres (270 mi) in diameter at its base, rises some 20 kilometres (12 miles) in height compared to the mean surface elevation of the planet, and is some 9 kilometres (5.6 miles) higher than the plains on which it sits. The caldera crater at its summit is 110 km (72 miles) across.

Continue reading “Space Sunday: conjunctions, volcanoes and space stations” →