Space Sunday: InSight, MarCO and privately to the Moon

A simulation of InSight touching down on Mars using its 16 rocket motors. Credit: NASA

On Monday, November 26th, 2018, the latest in a series of NASA missions, the InSight lander – built with international cooperation -, arrived on the surface of Mars.

As noted in my previous Space Sunday report, confirmation that InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) had safely arrived could only be received by mission control at NASA’s Jet Propulsion Laboratory (JPL) after the team there had endured the “seven minutes of terror”, more officially known as the Entry, Descent and Landing (EDL) phase of its journey, the time when the vehicle would enter Mars’ atmosphere and hopefully make a reasonably soft-landing on the planet’s surface.

While undeniably tense, when it came to it – and watched live via social media,  and assorted web broadcast channels put out by NASA – EDL was completed flawlessly. After separating from is cruise element around 7 minutes prior to EDL, InSight, protected by its heat shield and aeroshell, entered the upper reaches of the Martian atmosphere almost precisely on schedule, where over a 4-minute period, the frictional heat created by is passage helped decelerate it from an initial entry velocity of 19,800 km/h (12,300 mph) to 1,400 km/h (860 mph). At this point, telemetry once again being relayed, the supersonic braking parachute was been deployed.

After this things moved quickly: the heat shield was jettisoned from under the lander, which itself dropped free of the parachute and conical aeroshell, using its 16 rocket motors to achieve a “soft” landing on the surface of Mars – travelling at just 8 km/h (5 mph). A video compressing the seven minutes into just over a minute and a half captures the landing – and the joy at mission control (not the celebratory handshake at 1:19!).

It had been anticipated that the first “official” confirmation that InSight had arrived safely would be a “beep” sent directly to Earth from the lander’s X-band radio – and this might be followed a few minutes later by a photograph taken by the lander. As it turned out, and thanks to two tiny CubeSats – of which  more in a moment – it was the photo that arrived first. Grainy and indistinct due to it being taken by a camera still with its protected lens cap in place (itself splattered with dust), it shows a rocky surface and a tightly curved horizon – caused by the camera still being in its stowed configuration.

Side-by-side: (l) the first image returned by InSight using the lander-mounted, Instrument Context Camera (ICC), still with its dust cap in place – note the lander’s leg in the lower right corner. (r) a photo captured by the robot-arm mounted Instrument Deployment Camera (IDC), also taken with the lens cap in place, as the arm is exercised on November 30th, 2018. Credit: NASA/JPL

Initially after landing, InSight was operating on battery power whilst awaiting the dust to settle out of the atmosphere so the two circular solar panels could be deployed. This occurred some 30 minutes after touchdown, with the panels proving so efficient that . So efficient are these panels that during their Martian Sol of operation, they set a new record for power generation: 4,588 watt-hours – well over the 2,806 watt-hours generated in a single Sol by the “nuclear powered” Curiosity.

The efficiency of InSight’s solar arrays will deteriorate over time – the result of general wear-and-tear and the influence of dust that will inevitably accumulate on them – but the power levels have been more than enough for the lander to start flexing its muscles – including testing its robot arm, which is essential to it being able to place key experiments on the surface on Mars.

A computer simulation of InSight deploying its solar arrays. Credit: NASA

It is going to be early spring 2019 before InSight is fully involved in its science mission. There are a lot of equipment check-outs and calibration test to be undertaken, as well as the surface deployment of key instruments. However, there have been some external concerns raised over how well InSight will fulfil its science objectives. As data started coming back from the lander, it was noted that it had touched down in a shallow impact crater, almost completely filled by sand and dust (such craters being known as “hollows” on Mars), which has given InSight a 4-degree tilt.

Overall, the lander can in theory operate with up to a 15-dgree cant (the result of one of this three landing legs coming down on a boulder, for example), but here is a worry about how the tilt may impact placing the Seismic Experiment for Interior Structure (SEIS) and HP3, the Heat Flow and Physical Properties Package, on the surface of Mars, and how the material filling the hollow might affect the operation of HP3’s “mole”, which is designed to burrow into subsurface rock and measure the heat flow from the centre of the planet.

Computer simulation of Insight Placing the Seismic Experiment for Interior Structure (SEIS) experiment and its dust cover on the surface of Mars. Credit: NASA/JPL

Nevertheless the mission team remain in a positive mood and are delighted with both the landing and the first few days of operations.

We couldn’t be happier. There are no landing pads or runways on Mars, so coming down in an area that is basically a large sandbox without any large rocks should make instrument deployment easier and provide a great place for our mole to start burrowing.

– InSight project manager Tom Hoffman

Further examination of the lander’s surroundings will be made once the dust covers have been ejected from the on-board cameras, something that should happen in the next few days. This work will include a careful study of the ground to determine the best placement for SEIS and HP3, as well as a general surveying of the location, which in the initial images, appears a lot less rock-strewn than other locations visited by landers and rovers.

We are looking forward to higher-definition pictures to confirm this preliminary assessment. If these few images—with resolution-reducing dust covers on—are accurate, it bodes well for both instrument deployment.

– Bruce Banerdt, InSight principal investigator

I’ll have more on InSight as the mission develops.

MarCO Cubesats Paving The Way

Two of the heroes of the InSight EDL are a pair of tiny CubeSats – briefcased-sized satellites launched with InSight back in May 2018, and which separated from it at the start of the flight to Mars. They are called MarCO-A and MarCO-B (“MarCO standing for Mars Cube One – the name of the CubeSats mission), but nicknamed “Wall-E” and “EVE” after the stars of the 2008 Pixar film. Their purpose was to be technology demonstrators, acting as direct communications relays during InSight’s EDL.

Artist’s impression of the MarCO CubeSats, deployed by InSight while en route to Mars. Credit: NASA

Having the two CubeSats available meant InSight could communicate directly with mission control on Earth rather than having to wait for one of the vehicles already orbiting Mars to be overhead to act as a relay. As noted, this meant the first image captured by InSight was received within 10 minutes of touch-down. By comparison, confirmation that the solar panels had been deployed – which took place just 30 minutes after landing, as noted above – could not be confirmed for a further 4 hours, when NASA’s Mars Odyssey overflew the landing zone (the CubeSats were already out of range by the time of the solar panel deployment).

Neither of the two CubeSats could enter orbit around Mars as both were travelling too fast and had no means of slowing themselves on arrival. However, as the first interplanetary CubeSats mission, MarCO is an important milestone: not only did MarCO A and MarCO B allow an almost “real-time” monitoring of the InSight landing they demonstrated how such small, low-cost satellite systems could become an integral part of future missions to Mars and elsewhere.

In this latter regard, the potential of CubeSats could be limitless. Placed in orbit around a planet, for example, they could help form a global communications network, or be used for studying surface or atmospheric conditions.

Plans have already been put forward to use CubeSats as part of a return to the Moon in precisely these capacities and as a low-cost means of mapping the distribution of water and ice beneath the lunar surface. Other proposals include sending multiple CubeSats to study near-earth asteroids – something they could do at far lower cost than sending a “full size” robotic survey vehicle.

MarCO-B, one of the experimental Mars Cube One (MarCO) CubeSats, took this image of Mars from about 7,600 km (4,700 mi) after flying by the planet on November 26th, 2018, as InSight made its landing. This image was taken at about 20:10 GMT, after InSight had arrived on Mars the MarCO mission had achieved its primary goal. Credit: NASA/JPL

NASA is even examining using CubeSats as entry vehicles capable of entry into Jupiter’s atmosphere. Around half-a-dozen CubeSats could be flown to Jupiter, then individually released to drop into the planet’s atmosphere at different points. The advantages of using them would be that a) each would experience a much lower heat load a full-size probe would experience on entering Jupiter’s upper atmosphere, and therefore could dispense with much of the heavy and expensive heat shielding; and b) they could be used in concert to map and probe a much broader area of Jupiter’s atmosphere than could be achieved with a single, more complex probe.

Thus, while MarCO was only a demonstration mission, its success could herald a new era of CubeSat-based missions in the coming years.

The Next US Moon Landing Will Be By A Private Company – NASA

When we go to the Moon, we want to be one customer of many customers in a robust marketplace between the Earth and the Moon. We want multiple providers that are competing on cost and innovation.

– NASA Administrator Jim Bridenstine, November 29th, 2018

On November 29th, 2018, NASA announced nine US aerospace companies have been selected for future contracts to deliver payloads to the surface of the Moon.

These companies – ranging from the giant Lockheed Martin Space, through former competitors in the now defunct Google Lunar X-Prize (e.g. Moon Express), to small start-ups – are eligible for up to US $2.6 billion in NASA funding awards over the next ten years to develop landing craft capable of delivering NASA-defined science payloads to the surface of the Moon.

Lockheed Martin’s rover-carrying McCandless Lunar Lander, named the late astronaut Bruce McCandless who in 1984 performed the first free-flying spacewalk using the Manned Manoeuvring Unit, or “jet backpack”based, and on the successful Mars Phoenix / InSight lander designs, is one of the programmes that will receive NASA funding for placing science missions on the surface of the Moon. Credit: Lockheed Martin

The funding will come as part of NASA’s Commercial Lunar Payload Services (CLPS) programme, which is intended to run along similar lines to the current Commercial Crew Launch and the Commercial Resupply programmes being operated for the International Space Station. However, in making the announcement, NASA was – as has been the case of late – a little shy of going into specifics (delivery time-frames, amounts to be awarded, contractual requirements, etc.) whilst also being surprisingly bullish about the programme.

We’re going at high-speed, and they are becoming part of the catalogue, so to say. They will compete for tasks that we’re going to put out there weeks and months from now.

– Thomas Zurbuchen, NASA associate administrator for science

The only suggested frame of reference provided was that the first of these missions could take place in mid-2019, to coincide with the 50th anniversary of Apollo 11 landing on the Moon. However, given that is just 8 months away, it would seem unlikely, and most analysts are already pointing to mid-2020 being the earliest time frame for the first such landing.

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