Space Sunday: rockets, red spots, fireballs and spaceplanes

SpaceX's plan to start down the road to their first human mission to Mars with their 2018 automated mission to the Red Planet -which NASA suggest will cost the company around US $320 million
SpaceX’s plan to start down the road to their first human mission to Mars with their 2018 automated mission to the Red Planet – which NASA suggests will cost the company around US $320 million

NASA has indicated that the SpaceX Red Dragon mission to Mars, which the company plans to carry out in 2018, will likely cost around US $320 million for SpaceX to mount, ad NASA itself will spend around US $32 million over four years in indirect support of the mission.

The Red Dragon mission, first announced in April 2016, will be financed entirely by SpaceX; NASA’s costs will be related to providing technical and logistical support – such as using its Deep Space Tracking Network for communications with the vehicle.

If all goes according to plan, the Red Dragon mission could be launched as early as May 2018. It is the crucial first step along the road towards the company’s ambitions to land a human crew on Mars by the end of the 2020s. If successful, it could potentially be followed by at least three further uncrewed Red Dragon flights in 2020/22, prior to the company commencing work on building-up matériel on Mars in preparation for a crewed mission.

A SpaceX / NASA infographic outlining the 2018 mission
A SpaceX / NASA infographic outlining the 2018 mission. Credit: NASA / SpaceX

Red Dragon is the name of an uncrewed variant of the SpaceX Dragon 2 vehicle, which will enter service in 2018 ferrying astronauts to / from the International Space Station. Intrinsic to the mission is the plan to conduct a propulsive landing on Mars using the craft’s SuperDraco Descent Landing capability. This is vital on two counts.

For SpaceX, a crewed variant of the Red Dragon will likely be the Mars descent / ascent vehicle during a human mission to the planet. So understanding how it operates in the Martian atmosphere is a vital part of preparing to land a crew on the planet. NASA is similarly interested in learning how well retropropulsion works in slowing a vehicle to subsonic speeds in the Martian atmosphere, as it now looks likely they will use the same approach for their human missions to Mars, which may occur in the 2030s. Gaining the data from the SpaceX missions means that NASA doesn’t have to fly its own proof-of-concept missions all the way to Mars.

A Dragon 2 text article test-fires its eight SuperDraco engines during a hover test in 2014

Whether or not Red Dragon will fly in 2018 is still a matter of debate. SpaceX has some significant commitments and obligations on which to focus: commercial Falcon launches, resupply missions to the ISS, the start of crewed flights to the ISS, introducing the Falcon 9 into its flight operations, etc. These all tend to suggest that the development of the Red Dragon capsule, which will require some significant modifications when compared to the Dragon 2, will be subject to the company’s existing commitments taking priority over it.

In the meantime, the company plans to release more information on the overall Mars strategy, up to and including their human mission, in September.

Jupiter’s Great Red Spot: Atmospheric Heating for a Giant

As the Juno space vehicle reached the farthest point from Jupiter in its first orbit around the gas giant and begins a 23-day “fall” back towards the planet, scientists on Earth may have unlocked the secret of why Jupiter’s upper atmosphere is so warm.

The Eye of Jupiter: a CGI recreation of the Great Red Spot based on observations from the Voyager spacecraft and Hubble Space Telescope, and as used in the television series Cosmos: A Spacetime Odyssey. Credit: 21st Century Fox.
The Eye of Jupiter: a CGI recreation of the Great Red Spot based on observations from the Voyager spacecraft and Hubble Space Telescope, and as used in the television series Cosmos: A Spacetime Odyssey. Credit: 21st Century Fox.

Here on Earth, the atmosphere is heated by the Sun. However, despite being five times further from the Sun than Earth, the upper reaches of the Jovian atmosphere share similar average temperatures to our own when they should in fact be a lot colder. Many theories have been put forward as to why this is the case, but now a team from Boston University, Massachusetts,  believe they’ve found the answer: the heating of Jupiter’s upper atmosphere is the combined result of the Great Red Spot (GRS) and Jupiter’s aurorae.

The Great Red Spot is one of the marvels of our solar system. Discovered within years of Galileo’s introduction of telescopic astronomy in the 17th Century, it is a swirling pattern of red-coloured gases thought to be a hurricane-like storm raging down through the centuries in the Jovian atmosphere. Roughly 3 Earth diameters across, its winds take six days to complete one spin around its centre, driven in part by Jupiter’s own high-speed spinning about its own axis, completing one revolution every ten hours.

Continue reading “Space Sunday: rockets, red spots, fireballs and spaceplanes”

Space Sunday: China’s ambitions, Dawn’s success and Kepler’s return

China's space station, as it should look in 2022 (credit: China Manned Space Engineering)
China’s space station, as it should look in 2022 (credit: China Manned Space Engineering)

China has confirmed a series of ambitious new goals for its growing space endeavours, starting with the launch later this year of a new orbital facility, and progressing through 2018 with the launch of the core module for a large-scale space station, and which includes further mission to the Moon and to Mars.

The first orbital facility launched by China, Tiangong-1 (“Heavenly Palace-1”), was launched in 2011. Referred to as a “space station”, the unit was more a demonstration test-bed for orbital rendezvous and docking capabilities. While it was visited by two crews in 2012 and 2013, neither stayed longer than 14 days, and sinc 2013,  Tiangong-1 has operated autonomously, although it has suffered a series of telemetry failures in that time.

A model of Tiangong-2, which will be 14.4 metres (47 ft) in length, 4.2 metres (14 ft) in diameter and mass 20 tonnes, seen docked with a crewed Shenzhou ("Divine Craft") orbital vehicle on the left (Credit: unknown originating source)
A model of Tiangong-2, which will be 14.4 metres (47 ft) in length, 4.2 metres (14 ft) in diameter and mass 20 tonnes – almost 3 times the mass of the Tiangong-1 unit, seen docked with a crewed Shenzhou (“Divine Craft”) orbital vehicle on the left (Credit: unknown originating source)

Tiangong-2 will be launched later in 2016, and is designed to build on the experiences gained with the original facility, helping to pave the way for China’s first “genuine” space station. In particular, Tiangong-2 will provide an experiments bay, improved living facilities for longer-during stays, and allow China to verify key technologies such as propellant refuelling while in orbit, and undertake fully automated docking activities using uncrewed vehicles, when the nation’s first automated resupply vehicle, Tianzhou-1 (“Heavenly Vessel-1”) docks with the facility in 2017.

Tiangong-2 will be followed, in 2018 by the launch of the larger Tianhe-1 (“Sky River-1”) unit, which will form the core module for China’s first dedicated space station. Over the four years from 2018, this will grow with the addition of up to three other pressurised modules,  together with a docked “Hubble-class” space telescope. It be supported and maintained by automated re-supply mission from Earth using the Tianzhou, and provide living and working space for up to 6 crew,

A prototype model of the propsed Mars rover China plans to launch in 2020 as part of a 3-phase mission involved an orbiter / carrier vehicle, a static lander and the rover (credit:
A prototype model of the proposed Mars rover China plans to launch in 2020 as part of a 3-phase mission involved an orbiter / carrier vehicle, a static lander and the rover (credit: China National Space Administration)

Nor does it end there. At the end of March, I wrote about China’s aggressive approach to Mars exploration.

As a part of the series of announcements made by the Chinese authorities in the run-up to their first national Space Day on April 24th, 2016 – being the anniversary of the launch of China’s first satellite, Dongfanghong-1 (‘The East is Red’) – it was confirmed that the planned orbiter / rover mission to the red planet will be launched in 2020.

The rover element of the mission will build on experience gained during the deployment and operation of the Yutu vehicle on the Moon in 2013, and will be used to investigate the planet’s soil, atmosphere, environment, and look for traces of water.

As part of the preparations for this mission – although it is also a mission in its own right – China plans to land the its Chang’e-4 (“Moon Goddess”) probe, on the far side of the Moon in 2017, an operation which will be carried out fully autonomously of Earthside intervention.

To ensure all this happens, China is developing two new launch vehicle – the Long March 5 and the Long March 7. The Long March 5 will form the backbone of China’s space activities, offering a family of 6 launch vehicle variants, the largest of which will be capable of placing up to 25 tonnes in low Earth orbit (LEO), 14 tonnes in geosynchronous transfer orbit (GTO) for missions to the Moon, Mars or elsewhere, putting it in the same class of launch vehicles as America’s Atlas V and Delta IV launchers, and the commercial SpaceX Falcon 9 launcher.

Using non-toxic and pollution-free propellant, the 60-metre-long vehicle has a core diameter of 5 metres, and will be equipped with four strap-on booster 3.5 metres in diameter, Long March 5 is the first of China’s launch vehicles to specifically designed for both cargo / satellite launches and crewed mission launches.  The maiden flight of the vehicle is expected to be the Chang’e-4 mission to the far side of the Moon.

China's Long March 5 (l) and Long March 7 (r) next generation launch vehicles
China’s Long March 5 (l) and Long March 7 (r) next generation launch vehicles (credit: Sina Weibo)

The Long March 7 vehicle will be slightly smaller, capable of lifting 13.5 tonnes to LEO, although this will be enhanced over time to allow the vehicle to lift up to 20 tonnes to LEO. It will form the launch vehicle for the  Tianzhou resupply missions to Tiangong-2 and Tianhe-1, and over time will be uprated to crewed launch vehicle status. It is slightly smaller than the Long March 5, with a height of 53 metres, a core diameter of 3.35 metres, and used 4 2.25 metre diameter liquid-fuelled strap-on boosters. The first launch of a Long March 7 vehicle is expected later in 2016, when it lifts Tianzhou-1 for a rendezvous with Tiangong-2.

Continue reading “Space Sunday: China’s ambitions, Dawn’s success and Kepler’s return”

Space Sunday: bringing a rocket home; uncovering Ceres

A second from touchdown: the Falcon 9 first stage booster, with landing legs deployed, about to make a successful landing at "Landing Zone 1", Cape Canaveral Air Force Station, having been launched from the space facility 10 minutes earlier as a part of a flight to deploy 11 Orbcomm telecommunications satellites
A second from touchdown: the Falcon 9 first stage booster, with landing legs deployed, about to make a successful landing at “Landing Zone 1”, Cape Canaveral Air Force Station, having been launched from the space facility 10 minutes earlier as a part of a flight to deploy 11 Orbcomm telecommunications satellites

On Monday, December 21st, the private space launch company SpaceX achieved a remarkable first in the annals of space flight: they successfully launched a payload carrying rocket into orbit, and then returned its first stage to a safe landing back on Earth, close to its original launch point.

The Falcon 9 rocket, in its first launch since June 2015 when a fuel tank failure lead to the vehicle’s destruction together with the Dragon resupply vehicle it was lifting to the International Space Station, was lifting a total of 11 communications satellites into orbit on behalf of Orbcomm.

The booster lifted-off from Florida’s Cape Canaveral Air Force Station at 20:29 EST on Monday, December 21st (01:29 UTC, Tuesday December 22nd).  At 2 minutes 27 seconds into the flight, having pushed the vehicle through the densest part of the atmosphere, the first stage engines shut down, and shortly afterwards, the first and second stages separated, allowing the latter’s Merlin engine to ignite.

As the second stage continued to accelerate up to deployment orbit, the first stage coasted upwards before using cold gas thrusters to effectively “flip” the booster around so it could use the first in a series of “boostback burns” of its main engines to slow itself down as well as pushing it back towards Cape Canaveral.

With this completed, the booster used the cold gas thrusters to again flip itself over so it would be descending engines first towards the ground, performing two further “boostback burns” to control its descent before making a final engine burn during the last few dozen metres of the descent and deploying its 4 landing legs and steering vanes for a successful touch down some 10 minutes after lift-off, which was captured by cameras on the ground and aboard an observing helicopter.

The SpaceX success came less than a month after Blue Origin, the private space company founded by Amazon billionaire Jeff Bezos, also landed the initial stage of their New Shephard launch system following a test launch. However, the latter is not intended to achieve orbital velocities at present, and so the booster stage – referred to as the “propulsion module” by Blue Origin – was not travelling nearly as fast as the Falcon 9 first stage, nor did it have to perform the complex “boostback” manoeuvres.

In the meantime, the second stage continued upwards, successfully deploying the Orbcomm satellites into LEO – low Earth orbit, at around 630 kilometres (just under 400 miles) altitude. With this part of the mission completed, the second stage booster also re-ignited its main engine, allowing it to achieve a geostationary transfer orbit and coast phase.

This was as important as the first stage landing because, while existing Falcon 9 rockets are capable of placing large payloads into geosynchronous equatorial orbit, some 36,000 km (22,000 miles) above the surface of the Earth, it has required the first stage of the rocket to do much more of the work, leaving it with insufficient fuel reserves to attempt a return to Earth and landing. The uprated second stage, tested as a part of this flight, alleviates the first stage of some of the booster phase work, allowing it to retain the fuel it needs to make a successful return to Earth.

The overall hope with the upgraded Falcon 9 and the new landing facilities at Cape Canaveral, is that they will allow SpaceX to lower launch costs to the benefit of customers, and allow them to make more efficient use of their boosters rather than just tossing them away into the Atlantic or Pacific after a single use.

However, even with this first successful landing, the company still has some significant hurdles to clear. One of these will be demonstrating it can refurbish used first stages at a fast enough pace to be able to maintain a launch cadence high enough to be attractive to commercial operators looking for launch opportunities, rather than risking them look to those companies able to offer a faster launch rate.

Nevertheless, SpaceX’s achievement is clear, and after the disappointments in trying to recover the Falcon 9 first stage at sea (initially seen as a “safer” option due to the negligible risk of civilian injuries if anything went wrong when compared to  returning a rocket to Earth near populated areas), deserves every congratulation.

Dawn over Ceres

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

Dawn, the NASA / ESA joint mission currently mapping Ceres, one of the solar system’s three “protoplanets” located in the asteroid belt between the orbits of Mars and Jupiter, reached its lowest planned orbital altitude in early December, ready to start the final phase of its mission.

The new orbit, just 385 km (230 miles) above Ceres mains the craft can image the surface at a resolution of 35 metres (120 feet) per pixel.

Of particular interest to the science team has been determining the mysterious bright patches seen within the crater Occator during Dawn’s approach to Ceres and during its higher mapping orbits. While perhaps the largest found, the bright spots in Occator are not alone – around 130 bright spots have been located, almost all of them within Ceres’ craters, and analysis now shows that the material  seems to be consistent with salts, such as sulfates, with silicate materials also very likely present.

A false-colour representation Occator Crater on Ceres reveals the short wavelength of the bright deposits in the crater, pointing to them being salts. Occator measures about 90 km (60 miles) across
A false-colour representation Occator Crater on Ceres reveals the short wavelength of the bright deposits in the crater, pointing to them being salts. Occator measures about 90 km (60 miles) across

Continue reading “Space Sunday: bringing a rocket home; uncovering Ceres”

Space Sunday: of blood moons, Mars, Pluto and Ceres

A lunar eclipse "blood moon" seen Idaho, December 2011 (image: Matt Mills / Reuters)
A lunar eclipse “blood moon” seen Idaho, December 2011 (image: Matt Mills / Reuters)

The night of Sunday 27th / Monday 28th September  promises a very special astronomical event for those fortunate enough to have clear skies overhead and are willing to stay up late (in the UK and Europe). It will see a total lunar eclipse take place at the time when the Moon reaches perigee, its closest approach to Earth in its orbit and giving rise to both a so-called “supermoon” and a “Blood Moon”.

A “supermoon” occurs when a full moon coincides with the time when the Moon is nearing its minimum distance to Earth, a distance of roughly 363,000 kilometres (226,875 miles), leading to it appearing 7-8% larger than when seen as a full Moon at other points in its orbit. A “blood moon” is the result of the Earth’s atmosphere, lying between the Sun and Moon, scatter blue light more strongly than red, so the latter reaches the Moon more strongly, giving it a reddish-brown colour when seen from Earth.

A total lunar eclipse occurs when the Sun, Earth and Moon are lined up so that th Earth is between the Sun and Moon, and the later sits within the Earth's shadow
A total lunar eclipse occurs when the Sun, Earth and Moon are lined up so that the Earth is between the Sun and Moon, and the latter sits within the Earth’s shadow (image: NASA)

Lunar eclipses are not that rare – this one will be the second of 2015, for example. However, “supermoons” are somewhat rarer. The last was in 1982, and the next will not be until 2033. So, if you want to see a really big blood moon, and you live in Western Europe, West Africa, the Eastern side of the USA and Canada or south America, then the 27th / 28th September is the night to do so. People further afield – eastern Asia, the middle east, eastern Europe and the western sides of Canada, the USA and South America will see a partial eclipse.

In the UK, the period of eclipse will start at around 01:00 BST (00:00 GMT) on the morning of Monday, 28th September, and run through until around 05:00 BST (04:00 GMT). That’s from 20:00 through to around 01:00 EDT in the USA / Canada, and 02:00 through 06:00 CET in Europe).

A total lunar eclipse and the gradual change in the Moon’s colour as seen from Earth which sees total lunar eclipses sometimes referred to as “blood moons” – the result of sunlight passing through the Earth’s atmosphere and striking the Moon’s surface (animation: Wikipedia)

The eclipse brings to a close what is referred to as a “tetrad” of total lunar eclipses – that is, four occurring “back-to-back”, with no partial eclipses between them, the first of which occurred in April 2014 and the “middle two” in October 2014 and April 2015. Some have a misguided view that this “tetrad” as being of particular significance because such events are “rare”, and this particular one started on the Passover.

However, while there can be long periods of time between occurrences of tetrads, they can also pop-up relatively frequently. For example, this century will see a total of nine tetrads occur, the first having taken place in 2003/4. Nor is the fact that this particular series started on the Passover particularly unusual; there have been eight tetrads so far coinciding with Passover since the first century AD.

So, if you are in a position to see the eclipse, you can leave the tinfoil hat on the table and step outside quite safely. Totality should occur around two hours after the eclipse starts (e.g. 03:00 BST in the UK / 04:00 CET, 22:00 EDT on the 27th September), and that’s the best time to enjoy the blood moon in all its glory.

The eclipse will also give NASA the chance to measure the full range of temperature variations during  such an event. This will be done by the Lunar Reconnaissance Orbiter (LRO), a solar-power vehicle which has been observing the Moon since 2009.

Normally during an eclipse, the LRO has most of its systems powered down to reduce the load placed on the battery systems. However, mission controllers are confident they will be able to run an instrument which will allow it to accurately measure the amount of heat loss the surface of the Moon experiences when inside the Earth’s shadow, further helping them to understand the composition of the Moon’s regolith and its function as an insulator.

Continue reading “Space Sunday: of blood moons, Mars, Pluto and Ceres”

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

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

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”