GRAIL Arrival:

GRAIL-B achieved lunar orbit at 2:43 p.m. PST (5:43 p.m. EST) on Sunday, which completed the insertion of the spacecraft, after GRAIL-A successfully completed its burn at 2 p.m. PST (5 p.m. EST) the previous day.

The insertion maneuvers placed the spacecraft into a near-polar, elliptical orbit with an orbital period of approximately 11.5 hours.

Over the coming weeks, the GRAIL team will execute a series of burns with each spacecraft to reduce their orbital period to just under two hours. At the start of the science phase in March 2012, the two GRAILs will be in a near-polar, near-circular orbit with an altitude of about 34 miles (55 kilometers).

Their successful arrival followed a smooth launch via the 150th flight of the Delta II launch vehicle, which lifted off from SLC-17B at 09:08 Eastern on September 10, 2011.

Shortly after launch, the GRAIL spacecraft deployed their solar arrays as they passed into sunlight for the first time since separating from their carrier rocket. The transit for the GRAIL to the Moon involved a low-energy trajectory, via the Sun-Earth Lagrange 1 point (L1).

The spacecraft then had the key event of firing their main engines to enter a selenocentric, or lunar, orbit – as was carried out without issue. The spacecraft will subsequently manoeuvre into lower orbits, before they are moved into formation to begin collecting scientific data.

At the start of the scientific phase of the mission, the spacecraft will be in circular orbits at an altitude of 55 kilometres. Scientific operations are expected to commence on 8 March next year, and last for 82 days. Decommissioning of the spacecraft will begin on 29 May, and the spacecraft are expected to impact the lunar surface in June.

“NASA greets the new year with a new mission of exploration,” said NASA Administrator Charles Bolden. “The twin GRAIL spacecraft will vastly expand our knowledge of our moon and the evolution of our own planet. We begin this year reminding people around the world that NASA does big, bold things in order to reach for new heights and reveal the unknown.”

The GRAIL mission being flown as part of NASA’s Discovery program, which was started in 1992. Discovery is a medium-class programme intended to study the Solar system. many of NASA’s recent planetary missions have been conducted as part of it.

The principal scientific objectives of the GRAIL mission are to produce a map of the Moon’s lithosphere, to allow scientists to understand the Moon’s thermal evolution, and the evolution of breccia within the Moon’s crust, and to determine more details of the interior, particularly the size of the core, and the structure beneath impact basins.

The two spacecraft are identical, apart from the positioning of star trackers and instruments to allow the spacecraft to fly with their antennae pointing towards each other. They were built by Lockheed Martin, based around a bus developed for the USA-165, or XSS-11, satellite; a technology demonstration spacecraft operated by NASA and the United States Air Force, which was launched in 2005. Each GRAIL spacecraft has a mass of 307 kilograms, including 106 kilograms of hydrazine fuel.

The spacecraft are each equipped with two 1.9 square metre, 520-cell, solar arrays, which will generate at least 700 watts of power. The solar arrays will charge a 30 amp-hour lithium ion battery in each spacecraft, which will be used to store power for when the spacecraft are not in sunlight. Propulsion of each spacecraft will be provided by an MR-106L monopropellant engine, capable of generating 22 newtons of thrust.

The spacecraft are three-axis stabilised, with reaction wheels and eight warm gas thrusters, each capable of producing 0.9 newtons of thrust, being used aboard each spacecraft for attitude control. Sun and star trackers and inertial measurement units will allow the spacecraft to determine their orientation. The spacecraft carry avionics systems which are derived from those developed for the Mars Reconnaissance Orbiter, which was launched in 2005.

Each spacecraft carries two transponders operating in the IEEE S band (NATO E band), which will be used to relay data to the ground and to upload commands to the spacecraft. A further S band transponder, the Time-Transfer Assembly, will be used to transmit signals between the spacecraft to synchronise their onboard chronometers.

Two IEEE X band (NATO I or J band) transponders, the Radio Science Beacon, will be used to transmit signals to Earth for Doppler ranging. Finally an IEEE Ka band (NATO K band) transponder, the Microwave Assembly, will be used to find the distance between the two spacecraft, and track their relative motion.

The Ka band transponder forms part of the Lunar Gravity Ranging System or LGRS, which is GRAIL’s primary instrument. LGRS consists of four elements; the Ultra-Stable Oscillator, or USO, will be used to generate an oscillating signal to synchronise the instruments. This signal will then be transmitted through both the Microwave Assembly (MWA) and Time-Transfer Assembly (TTA) antennae.

TTA broadcasts the signal as a ranging code, similar to those transmitted by Global Positioning Satellites. Finally, the data is collected by the Gravity Recovery Processor Assembly, or GPA, which processes it for transmission back to Earth.

LGRS is derived from the K-Band Ranging (KBR) instrument aboard the Gravity Recovery And Climate Experiment, or GRACE, spacecraft, which were launched in March 2002. GRACE, like GRAIL, consists of two spacecraft using radio signals to map the gravitational field, however it is studying Earth’s gravitational field instead of the Moon’s.

The two spacecraft also carry the Moon Knowledge Acquired by Middle school students, or MoonKAM, student outreach payload. This will be used to image areas of the Moon at the request of schoolchildren.

A similar programme for Earth imagery, EarthKAM, has been operated aboard the International Space Station since 2001 and also flown on Space Shuttle missions STS-89 and STS-99. A prototype, KidSat, was also flown on STS-76, STS-81 and STS-86.

“I can’t think of a better way to ring in the New Year than to place two spacecraft into orbit around the moon. Our team is celebrating today,” said Stu Spath, GRAIL program manager at Lockheed Martin Space Systems Company. “We used the moon’s gravity to capture the two GRAIL spacecraft into orbit, and now the science team is going to analyze that same gravitational field to an extraordinary level.”

(Images via NASA and ULA).

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SLS Mission Ability – PART ONE:

The Roadmap – when announced – will lay out NASA’s flagship goals for the next 20 plus years. This task is under the stewardship of former Space Shuttle Program (SSP) manager John Shannon, who’s team have not released any information into their effort since it began months ago.

While the team is under no obligation to provide a running commentary to the public or media, the lack of a roadmap for SLS remains one of the main criticisms charged against the vehicle which will cost several billion dollars before it even flies.

However, while the November Human Space Exploration Community Workshop on the Global Exploration Roadmap – which is being serialized by this site – has provided some interesting mission options, the SLS Con Ops document – finalized just a few weeks prior to the workshop – reveals the actual foundation of SLS’ hardware, operations and indeed mission baselines.

Known as Exploration Systems Development (ESD) Design Reference Missions (DRM), the Con Ops document – available to download via L2 – introduces the SLS capability as one which provides multiple mission options, ahead of expanding into the current thought process for utilizing the vehicle’s unrivalled upmass capability.

“The SLS will have the largest payload lifting capacity of any launch vehicle previously manufactured in the United States: 70 metric ton (t) class evolvable to 130+ t class (ESD Requirement R-11),” noted the document in the introductory sections.

“This will allow the SLS to accommodate many mission profiles, starting with Orion missions for lunar fly-by and high lunar orbit and eventually deep space near Earth asteroid (NEA) and Mars missions that extend human presence across the solar system (requiring ~130 t).

“The SLS will also accommodate Orion-MPCV missions to low Earth orbit (LEO) for system test and checkout and as a back-up access to the International Space Station (ISS), including transport of replacement ISS modules. Other mission profiles that can be supported by the SLS include science-based missions for deep space astronomy and solar system exploration.

“The SLS payload capability will enable a new generation of planetary (such as a Europa fly-by to collect samples with return capability), Earth, and heliophysics science missions. SLS will also be capable of supporting commercial-based missions and missions supporting other Government agencies, including sending larger objects into LEO, such as commercial space stations.”

While the introduction provides little by way of additional substance into age-old adage of “Moon, Mars and Beyond” – as used by the now-defunct Constellation Program (CxP), the document goes on to provide an expansive and up-to-date overview of the DRMs, whilst adding the caveat the missions may not occur in any particular order and are not set requirements, but are used as a framework to ensure SLS capability.

“The ESD DRMs are categorized as Tactical, Strategic, Architecture, and Analysis timeframe DRMs. The Tactical Timeframe DRMs are intended to reduce overall design risk and help to preserve operations capabilities by allowing missions to be flown earlier in the design process,” the document notes.

“The Strategic DRMs build on the capabilities demonstrated in the Tactical timeframe to ensure a path to achieve the operational capabilities as laid out in the ESD Requirements. The collection of these DRMs is the architecture framework necessary for multi-destination exploration.

“The Architectural timeframe DRMs address the missions where evolved capabilities will be needed to achieve the long-term exploration objectives. These DRMs are critical in understanding the requisite system functionality, and deriving the Program-specific operations block designs that will enable an effective block delivery evolution path. Analysis DRMs are candidate DRMs that are under formal ESD consideration. Analysis will be performed on these DRMs as part of a cost/benefit assessment.

“Once ESD leadership has determined the status of an analysis DRM, the DRM will either be added to the appropriate timeframe DRMs or will be discarded. While programs will need to perform some level of analysis to support this decision-making process, the analysis that supports the evolvability design assessments is not necessary for Analysis DRMs.”

The wording of the above shows some of the challenges of formulating the definitive exploration plan – and the likely reason that as of today such a plan does not exist. NASA’s future plans continue to be hindered by a budget that lacks stability, as much as lawmakers have shown their hand in wishing to protect SLS and Orion from such budget fluctuations.

Ironically, one area of NASA funding which is being subjected to uncertainty is the commercial handover of Low Earth Orbit (LEO), not least from the commercial crew standpoint. With threats of slips – based on lower-than-expected funding and internal technical challenges – there is potential for the need of a back-up, as SLS was intended to be – per the 2010 Authorization Act – for the International Space Station.

However, with SLS’ opening mission – one which is BEO in design – not set to fly until 2017, such slips would have to be serious in nature for NASA to use a vehicle which is now designed specifically for exploration, as opposed to LEO.

Regardless, the back-up ability to transport four crew members on Orion, launched on a basic SLS, opens the DRM list.

“ISS Back-Up Crew Delivery (Analysis): The International Space Station (ISS) Back-Up Crew Delivery mission (DRM ID: LEO_Util_1A_C11A1) is flown with the SLS and the Orion-MPCV, with SLS providing any necessary ballast and launch stack spacers,” noted the presentation.

“This DRM is a single launch of up to four crew members to and from the ISS and is a back-up to the planned commercial crew capability for transportation to the ISS. This mission is flown using the Block 1 SLS without an iCPS.”

The next DRM is currently in the documented approach for SLS’ opening mission in 2017, one that involves an uncrewed test flight around the Moon, on a mission which – according to Con Ops – will last around eight days.

“BEO Uncrewed Lunar Fly-by (Tactical Timeframe): This mission uses a single Block 1 SLS launch with an iCPS and lunar Block 1 Orion-MPCV. This DRM will go beyond Earth orbit (BEO) and test critical mission events and performance in relevant environments,” the Con Ops document noted.

“It will take 3-4 days of transit time, with the Orion-MPCV trajectory taking it around the Moon performing burns as required, and then 3-4 days to return to Earth. The liftoff mass will be approximately 66 t.”

SLS-2 will carry out a similar mission, this time with a crew. Initially manifested for 2021 on the “worst case” scenario, moves have already been made by the Orion Project office to push this up to 2019, or potentially 2018. This mission will last around 14 days, with four days in Lunar orbit.

“BEO Crewed Lunar Orbit (Tactical Timeframe): This mission requires a single Block 1 SLS launch with an iCPS and Lunar Block 1 Orion-MPCV to LEO. It will take 4-5 days of transit time, 4 days in lunar orbit, and 4-5 days for return to Earth. The liftoff mass will be approximately 66 t.

“The iCPS performs the orbit raise burn and TLI (Trans-Lunar Injection) burn prior to disposal. When approaching high lunar orbit, the Orion-MPCV provides the lunar orbit insertion (LOI) burn to insert the Orion-MPCV into a high lunar orbit. The Orion-MPCV will remain in lunar orbit for several days and then perform a trans-Earth injection (TEI) burn and return to Earth.

“The lunar orbit will be selected to maintain the total delta-V for LOI and TEI maneuvers within the Orion-MPCV design capability.”

Opportunities to collect data on the hardware – most notably on Orion’s performance – will be taken via the Exploration Test Flight (EFT-1), scheduled for early 2014.

While these two missions appear to be the most solid part of the short-term mission plan for SLS and Orion, everything that follows is open for evaluation. However, the DRM content in the Con Ops provides multiple options, along with clues as to how such missions would be conducted.

One such example can be found under the DRM of a mission to Geostationary Orbit (GEO), utilizing two SLS launches, 180 days apart. Such a DRM scenario also dismisses the worst-case scenario which shows a maximum near-term flight rate of one launch per year – which would clearly be uneconomic for the HLV.

“GEO (Analysis): The GEO vicinity mission (DRM ID: CIS_GEO_1B_C11B1) requires two SLS launches, with the first carrying CPS1 and a cargo hauler. The second launch, approximately 180 days later, will contain CPS2 and the Orion-MPCV,” noted the overview.

“The mass-to-orbit for both launches will be approximately 110 t each. This would allow crew to perform servicing or deployment missions in GEO, depending on the payload inside the cargo hauler.”

Reverting back to aspirations involving the Moon, the next DRM has seen a large increase in interest over 2011, namely a mission to return humans back to the surface of the Moon.

Work appears to be making good progress on setting up a preferred flight profile for such a Lunar Surface, with one of three options set for deletion. Two of the options can be carried out prior to the evolved SLS coming on line.

“Lunar (Strategic and Architecture Timeframes): The lunar set of missions ranges in distance from lunar vicinity Lagrange Point 1 (L1), to low lunar orbit, to a lunar surface mission,” noted the ConOps.

“The first two of the three mission set, lunar vicinity and low lunar orbit (DRM IDs: CIS_LP1/LLO_1A1A_C11B1, Concept of Operations), which are in the Strategic timeframe, require one SLS launch with the Orion-MPCV and CPS to L1 or low lunar orbit (LLO). The mass-to-orbit for these two missions are approximately 90 t and 95 t, respectively.

“It should be noted that the low lunar vicinity DRM (CIS_LP1_1A_C11B1) is under ESD review for removal.”

The third option requires two SLS launches, this time around 120 days apart. However, the liftoff mass requires the use of the evolved SLS, pushing such a mission out to at least the late 2020s. See SLS configuration option latest (Block 1, 1A, 2) via L2. 

“The lunar surface mission (DRM IDs: LUN_SOR_1A1A_C11B1, ESD Concept of Operations), which is in the Architecture timeframe, requires two launches, spaced 120 days (TBR) apart, to insert the lunar lander and CPS1 and Orion-MPCV and CPS2 into LLO for a lunar orbit rendezvous (LOR) and landing on the equatorial or polar regions of the Moon. The liftoff masses will be approximately 130 t and 108 t, respectively.”

No reference is made to the fascinating proposal relating to the Exploration Gateway Platform architecture that not only returns man to the lunar surface – via the use of only one SLS launch to a reusable Lunar Lander – but provides a baseline for pathfinders towards an eventual crewed mission to Mars.

However, internal meeting notes (L2) just this month show this L2 gateway is now under official consideration, with mission options being evaluated at present.

“NASA Human Architecture Team (HAT): L2 based DRMs being developed,” noted the Strategic Analysis and Integration Division (SAID).

Such a plan revolves around a deep space platform, known as a gateway, located at Earth-Moon Lagrange (EML) point 1 or 2, after being built from pre-launched hardware, providing the host station for a reusable Lunar Lander – which would also be launched by the SLS.

The Gateway would first be constructed at the ISS, mainly using the Node 4/DHS (Docking Hub System), an orbiter external airlock, an MPLM (Multi-Purpose Logistics Module) habitat module, and an international module.

Further articles on the Gateway will be forthcoming, along with Part 2 to the ESD DRMs from the ConOps, which cover missions to Near Earth Asteroids, SLS science missions to as far out as Enceladus, and Department Of Defense (DOD) missions.

Please note following trial run: Clickable GOLD links with (L2) references point directly to cited L2 content. Such content is only available to L2 members (please ensure you are logged in). Clickable BLUE links point to NSF articles and open content.

Images: Via L2 content, driven by L2′s fast exapanding SLS specific L2 section, which includes, presentations, videos, graphics and internal updates on the SLS and HLV, available on no other site. Other images via NASA.)

(L2 is – as it has been for the past several years – providing full exclusive SLS coverage, available no where else on the internet. To join L2, click here: http://www.nasaspaceflight.com/l2/)

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Lunar Surface Option:

Created under what turned out to be an expansive amount of evaluations at the Global Exploration Workshop in November, Boeing’s Moon Mission Concept with a re-usable Lunar lander has raise eyebrows in internal circles.

Using a Global Exploration Roadmap, the approach utilizes “Near term focus on guiding capabilities, technologies and leveraging ISS,” prior to expanding to “Long term focus (on) Discovery Driven – and Enhanced by – Emerging Technologies”.

While such talk has been heard before, during the continued lack of an exploration roadmap that can provide any real definition, the presentation makes the jump towards a mission goal which has seen its stock raised over recent months, one which involves the crewed return to the Lunar Surface, as the opening prime exploration mission for NASA.

Currently, Orion’s opening two missions via the Space Launch System (SLS) are Lunar flights, but ones which do not result in footsteps on the Moon’s surface. The first uncrewed mission is scheduled to launch in 2017, followed by a crewed Apollo 8-style mission, officially manifested for 2021, as much as work is continuing to push this mission to the left by at least two years.

This will mark the first time humans have ventured out of Low Earth Orbit (LEO) for decades.

Work is continuing – under the leadership of former Space Shuttle Program (SSP) manager John Shannon – on an exploration roadmap, of which there are no official details. Rumors of some sort of a plan being revealed in November are now likely related to the workshop, as opposed to a much-wanted centralized plan.

However, the same source information (L2) did note the November meeting would include proposals from advocates of a Lunar landing mission in the early 2020′s – known unofficially as – Lunar Surface First – as has turned out to be the reality.

Returning to the Lunar surface – which would follow after SLS-1 and SLS-2 – was the initial stepping stone for the now-defunct Vision for Space Exploration (VSE), centered around Ares, Orion and the Altair lunar lander.

The current plan is vague, with references to a Near Earth Object (NEO) mission in the mid 2020s, on a path to crewed missions to Mars in the 2030s. However, documentation now exists, based around a crewed return to the moon as part of an ambitious plan put forward under the Boeing banner.

Central to the plan is a deep space platform, known as a gateway, located at Earth-Moon Lagrange (EML) point 1 or 2, after being built from pre-launched hardware, providing the host station for a reusable Lunar Lander – which would also be launched by the SLS Heavy Lift Launch Vehicle (HLV).

The Gateway would first be constructed at the ISS, mainly using the Node 4/DHS (Docking Hub System), an orbiter external airlock, an MPLM (Multi-Purpose Logistics Module) habitat module, and an international module.

Such a concept was previously overviewed in August, showing how the existing hardware would be launched to the ISS – using Atlas launch vehicles in the example cited – prior to full assembly using ISS assets such as the Space Station Remote Manipulator System (SSRMS).

Once constructed, a space tug – powered either by solar electric or chemical – would be utilized to raise the platform to the EML point. Such a proposal claims to be ready for the arrival of crewed missions via the SLS by 2022 – as much as any timeline would be based on the readiness and evolvability of the SLS.

“A Gateway at EML1 or EML2 allows re-usability of the lunar lander which saves money and enhances development of the ultra-reliable systems needed for Mars,” noted the November presentation.

“Our concept lander is much smaller than Altair; Dry mass of 7t, wet mass of 15t (Altair was ~45t wet). The propulsion system is designed to be re-fuelable LOX/Methane.”

EML-1 is a preferred point, based on previous documentation, such as the 726 page HLV “final” assessment presentation (available on L2) – which mainly covers the use of a Sidemount HLV, as much as it covers the now confirmed In-line configuration – via a section called the “Open Architecture – NASA Crew Elements and Commercial Propellant example, showing “L1 Enables Anywhere, Anytime, Global Access.”

HLV capabilities for higher energy missions beyond LEO were examined. This required the use of upper stages. Existing stages from Delta IV and Atlas V and new stage designs using RL-10B2 (existing), RL-60 and J-2X LOX/LH2 rocket engines (as now chosen) were used to estimate payloads to Geosynchronous Transfer Orbit, Geosynchronous Orbit, Trans-Lunar Injection and to the Earth-Moon L1 point,” the presentation noted.

For SLS/HLV Articles, click here: http://www.nasaspaceflight.com/tag/hlv/

This use of EML-1 related to the launch of a single HLV, carrying a depot to be refuelled using commercial vehicles, reducing the mass required to launch from Earth’s surface on a Lunar or deep space mission via “dry” – and potentially reusable – landers.

“A propellant depot at the Earth-Moon L1 point would significantly improve lunar and deep space exploration mission operations by providing an infrastructure capability for deep space transportation and by opening up participation to international partners and commercial vehicles. This propellant depot outside of Earth gravity well would act as a refuelling station for spacecraft on the way to the lunar surface or Mars,” added the presentation.

Such a plan would result in SLS with an EDS (Earth Departure Stage) delivering Orion and a dry lunar lander to L1. The dry lunar lander would be loaded with 25mt of propellants at the depot to complete the lunar phase of its mission. Dry launch of the LSAM element to L1 would dramatically reduce the spacecraft weight constraints, permitting more flexible and robust operational capabilities to be designed into the lander.

While the main focus of a fuel depot would be angled towards a broader use of propellent refueling – in effect a gas station in space where fuel would be stored in-situ – the November presentation takes a secondary approach, by having a ready to use platform already at L1, with fuel for the lander arriving via the SLS ready for immediate transfer.

In fact, the first customer to arrive at the platform would likely be the dry lander, while the gateway station was still located at the ISS, prior to the entire stack being sent into deep space via a tug.

“Commissioning crew flies with the lander to the platform,” added the presentation. “Flight test program in the vicinity of the ISS-EP is used to prepare the lander for it’s first landing.”

Once all the hardware is in place at EML-1, the presentation claims there is potential for a single SLS to carry out a full lunar surface mission, as much as the key will be on the evolution of the SLS’ third stage.

In essence, the potential scenario calls for: The launch of the station/gateway platform to Earth-Moon L1 or L2, via a space tug, following assembly at the ISS. Potentially the launch of a reusable LOX/methane lander to the L1/2 Gateway – as much as it’s likely the lander would be sent to the gateway whilst it was still at the ISS. The Launch of the SLS with an Orion and a modified Delta Cryogenic Second Stage (DCSS) to the Gateway.

The scenario then calls for the use first burn of DCSS to stop at Gateway and dock, where it would transfer LOX and methane from DCSS to lander – with the methane stored in an extra tank in-between LOX and LH2. The mission would then be initiated, with a lunar landing using the DCSS to inject to the Moon, with around three DCSS burns being utilized.

The crew would then return to Gateway Platform in the lander, transfer themselves over to the berthed Orion, and return to Earth with a burn from Orion’s SM. It should be noted that all of the key elements would likely be refined prior to a complete plan, as noted in the presentations operational considerations.

However, one of the key benefits of this approach is noted as the saving of potentially billions of dollars to carry out such recurring missions, while “unique science opportunities at L1 Deep-space human exploration analogs exist at L1. (Provides) support for deep-space human exploration missions.”

“The goal for recurring operations should be to deliver the crew and all fuel for the lander in a single SLS launch,” added the presentation.

“The SLS third stage acts as the descent stage for the lander and performs the lunar orbit injection burn as well as most of the lunar descent burn. This allows for the most efficient use of propellant because the high energy LOX/LH2 third stage is used immediately after it gets to L2 and long term storage of LH2 is not required,

“The expensive crew cabin and ascent stages are reused for multiple missions saving billions of dollars.”

Other benefits of a gateway platform are also cited in the overview, such as the potential for telerobotic control of hardware on the lunar surface, the launching of lunar habs to the Moon’s surface, and further references to using this baseline to ramp up towards Mars missions.

(Images: Via L2 content, driven by L2′s fast exapanding SLS specific L2 section, which includes, presentations, videos, graphics and internal updates on the SLS and HLV, available on no other site. Other images via Boeing and NASA.)

(L2 is – as it has been for the past several years – providing full exclusive SLS coverage, available no where else on the internet. To join L2, click here: http://www.nasaspaceflight.com/l2/)

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A look back into History:

The amazing LRO images – now released by NASA – show details which even include the actual footprint paths made when the astronauts explored the lunar surface during the Apollo missions.

Other easily identifiable areas – such as in the Apollo 17 site – include the tracks laid down by the lunar rover, along with the last foot trails left on the moon.

At each site, trails also run to the west of the landers, where the astronauts placed the Apollo Lunar Surface Experiments Package (ALSEP) to monitor the moon’s environment and interior.

LRO – which was built and managed by NASA’s Goddard Space Flight Center – managed to take the higher resolution photos via adjustments made to the spacecraft’s orbit, which is slightly oval-shaped or elliptical.

The maneuver lowered LRO from its usual altitude of approximately 31 miles (50 kilometers) to an altitude that dipped as low as nearly 13 miles (21 kilometers) as it passed over the moon’s surface. The spacecraft remained in this orbit for 28 days, long enough for the moon to completely rotate.

This allowed for full coverage of the surface by the LROC’s Wide Angle Camera on the spacecraft.

“The new low-altitude images sharpen our view of the moon’s surface,” said Arizona State University researcher Mark Robinson, principal investigator for the Lunar Reconnaissance Orbiter Camera (LROC). “A great example is the sharpness of the rover tracks at the Apollo 17 site. In previous images the rover tracks were visible, but now they are sharp parallel lines on the surface.”

“Without changing the average altitude, we made the orbit more elliptical, so the lowest part of the orbit is on the sunlit side of the moon,” added Goddard’s John Keller, deputy LRO project scientist. “This put LRO in a perfect position to take these new pictures of the surface.”

The cycle ended on Tuesday, resulting in the spacecraft returning to its 31-mile orbit around the Moon.

“These images remind us of our fantastic Apollo history and beckon us to continue to move forward in exploration of our solar system,” said Jim Green, director of the Planetary Science Division at NASA Headquarters in Washington.

Protecting the Lunar Sites:

The amazing images were published just days ahead of the Delta II mission to launch GRAIL (Gravity Recovery and Interior Laboratory) – twin lunar satellites – to the Moon on Thursday, which lift-off scheduled for 8:37am Eastern from Cape Canaveral Air Force Station (CCAFS).

The images also arrived shortly after an expansive internal NASA presentation – available on L2 - was debated at a NASA Staff Senior meeting in August, which discussed the protection of the heritage sites from future landers and robotic vehicles.

Such new arrivals in the near future include private robotic landers, such as those competing for the Google Lunar X PRIZE (GLXP) – as heavily referenced in the associated NASA presentation.

The GLXP has a prize fund of $30 million available to the first privately funded teams to safely land a robot on the surface of the Moon, have that robot travel 500 meters over the lunar surface, and send video, images and data back to the Earth.

There are currently 29 teams working on winning the GLXP, with $20 million on offer for the winner. The targeted landing sites for these teams are located all around the lunar surface.

According to the NASA presentation there is scientific interest in robotic visits to the Apollo sites, allowing for the collection of data on items such as dust transportations, Micrometeorite bombardment rates, sandblasting effects, the survival of microbes and Lunar Weathering.

“To characterize the effects on engineered materials following four decades of exposure to the lunar environment,” the presentation noted on the latter scientific item of interest.

However, there is a concern relating to the possible mechanisms of damage to the aforementioned “scientifically interesting data” as NASA worded it.

Fears include the proximity of landing, liftoff and flyover from a future landing/robotic vehicle, where rocket thrust may erase footprints and treads, sandblast nearby hardware and cause deposition of chemicals/dust.

There are also concerns relating to robotic rovers accidentally running over the footprints created by Apollo astronauts, or contaminate a site via physical contact with heritage hardware.

One of the worst case scenarios listed relates to the potential of Entry, Descent and Landing (EDL) errors, resulting in a “crash or off-nominal landing near a heritage site which may produce enormous amounts of debris, dust, chemical contamination, and possible biological contamination.”

Some data is already at hand via the actual Apollo missions, such as the “Plume/Ejecta particle analysis for Lunar Descent Engines” findings, which show the descent engines create a high velocity of horizontal flow across the lunar surface.

The data – as presented in the NASA document – notes that the force creates a “relatively flat sheet of dust – 1-3 degrees to surface – with particles lifted by aero forces. Total eroded and scouring volume is around two metric tons in volume, with dust velocities reaching as high as 2000 meters per second.”

As such, NASA created a set of recommendations for preserving/protecting the USG Lunar Artifacts, relating to three categories, ranging from the six Apollo sites, the unmanned soft-landing sites of Surveyor and Luna, and through to the impact/crash sites of Ranger and the expended S-IVB stages.

Among the recommendations cited in the presentation, the arrival of future craft – such as the GLXP vehicles – should follow certain flight rules, in order to provide protection for the heritage sites.

“The approach path for the Descent/Landing (D/L) trajectory should be tangential to the D/L boundary in order to protect the site from off-nominal descent/landing situations,” the document noted. “The visiting vehicle should ensure no overflight of the heritage sites.”

The recommendations add additional emphasis for the Apollo 11 and Apollo 17 sites, making reference to a “Keepout Zone”.

“While all the Apollo sites represent significant historical/heritage value in the material culture, the Apollo 11 and 17 landing sites carry special significance,” added the presentation.

“It is recommended that the sites for Apollo 11 and 17 be treated as unique by prohibiting visits to any part of the site (and) that all vehicles remain beyond the boundaries of the entire site.

“It is recommended that the entire site at Apollo 11 and 17 be restricted from close inspection by visiting robotic systems. The visiting vehicle mobility exclusion boundary will encompass all artifacts (hardware, footprints, etc) for this site.”

The exclusion zone for Apollo 11′s site will result in a keep-out zone of 75 meters from the lunar module descent stage, where as the zone will extend 200-225 meters from the Apollo 17 site.

However, for the Apollo 12, 14, 15 and 16 sites, more access should be provided to individual components and artifacts, NASA added, allowing for future robotic missions to get within touching distance of Apollo hardware – as much as they won’t be allowed physical contact.

This additional access is shown as buffer zones, with a three meter buffer for descent stages, one meter buffer distance for the Lunar Rovers, experiments, sampling sites and flags, while no restrictions are recommended on the footprints and rover tracks outside the identified keep-out zones.

These buffer zones will also apply to other spacecraft, such as a one meter buffer around all Surveyor spacecraft hardware. A ruling is also provided for the expended S-IVB stage impact site.

“Rovers may drive to the rim of the crater and observe,” added the presentation. “Entrance into the crater may be permissible with coordination with NASA, but may not disturb any debris.”

An additional note on the restrictions at the Apollo 12, 14-16 sites, is also listed, relating to the Laser Ranging Retro-Reflectors (LRRRs), which the presentation notes should be carefully preserved.

“The LRRRs should be treated as special cases with approach mobility being tangential to the site. Once within a 10 meter radius zone of the LRRR, mobility can only proceed at speeds that do not propel regolith particles forward of the rover up to the total exclusion zone of one meter radius around the retro-reflector.

“Direct approach to the LRRR should never occur.”

Several pages of additional rules and allowances are listed for landers in the hopper configuration, along with the potential that the GLXP missions may provide additional science opportunities and data to use in refining their rulings.

As such, NASA class the recommendations as an evolving document, based on early, small landers with imaging only. Such lander capabilities are likely to advance over the short-term.

Forward work will also include analysis on rocket exhaust interaction with the lunar regolith to attempt to reduce the D/L distance.

(Images: Via the NASA Presentation – available in L2, NASA images via the LRO photo release. The lunar landing site map is originally available here: http://evadot.com/glxplandingsites/)

(As the shuttle fleet retire, NSF and L2 are providing full transition level coverage, available no where else on the internet, from Orion and SLS to ISS and COTS/CRS/CCDEV, to European and Russian vehicles. 

(Click here to join L2: http://www.nasaspaceflight.com/l2/ )

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The PSLV-C11 is an uprated version of ISRO’s Polar Satellite Launch Vehicle standard configuration. Weighing 316 tonnes at lift-off, the vehicle uses larger strap-on motors (PSOM-XL) to achieve higher payload capability.

LIVE EVENT PAGES FOR LAUNCH (Includes free launch video) AND MISSION

Since 1993, the vehicle has achieved twelve successful launches carrying satellites to Sun Synchronous, Low Earth and Geosynchronous Transfer Orbits, launching 29 satellites in total.

The Vikram Sarabhai Space Centre (VSSC), Thiruvananthapuram, designed and developed PSLV-C11, which is 44.4 metres tall and has four stages using solid and liquid propulsion systems. The first stage, carrying 138 tonne of propellant, is one of the largest solid propellant boosters in the world.

Six solid propellant strap-on motors (PSOM-XL), each carrying twelve tonne of solid propellant, are strapped on to the first stage. The second stage carries 41.5 tonne of liquid propellant. The third stage uses 7.6 tonne of solid propellant and the fourth has a twin engine configuration with 2.5 tonne of liquid propellant.

Chandrayaan-1 will carry out high-resolution remote sensing of the Moon on a global scale. It will study lunar surface composition, produce a 3D map of the Moon’s surface and drop an impact probe for added surface studies.

Following launch, Chandrayaan-1 will travel for about five and a half days to the Moon. The final operational orbit (polar, circular at 100-km altitude) will be reached about two weeks later.

Two NASA instruments to map the lunar surface will launch on Chandrayaan-1, which consist of the Moon Mineralogy Mapper, which will assess mineral resources, and the Miniature Synthetic Aperture Radar, or Mini-SAR, which will map the polar regions and look for ice deposits.

Data from the two instruments will contribute to NASA’s increased understanding of the lunar environment ahead of its project return to the moon via Orion in 2019.

“The opportunity to fly NASA instruments on Chandrayaan-1 undoubtedly will lead to important scientific discoveries,” noted NASA administrator Michael Griffin. “This exciting collaboration represents an important next step in what we hope to be a long and mutually beneficial relationship with India in future civil space exploration.”

In addition to the two science instruments, NASA will provide space communications support to Chandrayaan-1 during its two-year lunar mission.

The spacecraft also will carry four instruments and a small lunar impactor provided by ISRO, and several instruments from the Europe Space Agency (ESA).

This cooperation follows on from the first venture between India and Europe, which took place in the 1980s. In 1981, Europe’s Ariane 3 rocket launched into space India’s first geostationary satellite Apple.

Riding onboard, Europe’s Compact Imaging X-ray Spectrometer (CIXS) will carry out high-quality, low-energy (soft) X-ray spectroscopic mapping of the Moon. The Infrared Spectrometer, known as SIR-2, will observe the chemical composition of the Moon’s crust and mantle.

Both of these instruments were flown on SMART-1 and have been upgraded and rebuilt for Chandrayaan-1. They will continue the work on surface composition started by the original instruments.

The third European contribution is the Sub-keV Atom Reflecting Analyser (SARA). Derived from the ASPERA (energetic neutral atoms analyser) instruments, flown on Mars Express and Venus Express, it will be the first lunar experiment dedicated to direct studies of the interaction between electrically charged particles and the surface of the Moon.

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