Lunar Vertex rover

Overview

Reiner Gamma is a crustal magnetic anomaly colocated with the type example of a lunar swirl, and the competing explanations for both, an ancient dynamo against impact- or plasma-related processes, are separated by how the magnetic field varies across the anomaly and by what the regolith looks like away from a single landing point [28]. A fixed lander payload measures one location; answering the question requires a second measurement some distance away, which is what the rover is for.

Lunar Vertex is the first delivery selected under NASA’s Payloads and Research Investigations on the Surface of the Moon program, the line the 2023-2032 planetary science decadal survey names alongside Endurance-A as the vehicle for CLPS-delivered lunar science [4]. The rover is the mobile half of that payload, riding to Reiner Gamma on an Intuitive Machines Nova-C lander under NASA’s Commercial Lunar Payload Services initiative, the same delivery arrangement Intuitive Machines advertises as carrying science instruments, rovers and a short-range hopper on one lander bus with roughly 130 kg of surface payload capacity and hazard-avoidance landing to a 10-degree maximum slope [1]. The vehicle itself is a variant of Lunar Outpost’s Mobile Autonomous Prospecting Platform (MAPP), a product line the company markets as capable of high payload capacity at low mass and terrain access into craters and rugged outcroppings [2]: Lunar Outpost builds and operates it on the surface, and the Johns Hopkins Applied Physics Laboratory integrated the science instruments into the chassis and ran environmental testing on the assembled system [28].

That division of labor, a laboratory buying a small commercial rover as an instrument carrier rather than building a chassis, is a pattern repeated elsewhere on the same Nova-C class of lander: CADRE, three small JPL rovers sharing state through a SQLite-backed database over a mesh radio limited to roughly 1 Mbps aggregate, flew as a technology demonstration on the following Intuitive Machines mission rather than as a chassis built in-house [13], and it follows from the same CLPS economics that make a lunar swirl investigation affordable at all, a fixed-price commercial ride rather than a dedicated agency mission; the same lander family has also carried a hopper, S. P. Hopper, as a separate IM-2 payload element built with Arizona State University and DLR rather than by Intuitive Machines itself [11]. The chassis arrived at APL in spring 2023, instrument integration and environmental testing followed, and the integrated rover was delivered to Intuitive Machines in January 2024 [29].

Neither of the science-team abstracts publishes a chassis specification for this flight unit. The APL project page gives a stowed or deployed height of 35 cm, read off an artist’s impression rather than measured, and a planned maximum traverse range of 2 km from the lander, stated as a mission target rather than a demonstrated distance [30]. No mass, wheel diameter, drive speed, slope limit, obstacle capability, power, battery capacity or processor figure has been published for this vehicle at all. The closest thing to a general chassis figure, 10 kg total mass and a top speed of 10 cm/s for the MAPP product line, comes from a payload team riding a sibling rover on the previous Intuitive Machines lander, quoted secondhand from the vendor with no independent measurement behind it [3], and it is not stated to apply to this flight unit. That earlier flight, Lunar Voyage 1 on Intuitive Machines’ second lander, is the only account of a MAPP-family vehicle actually operating: the lander came down on its side with the rover’s garage wedged shut, so the rover was powered up, commanded and returned telemetry within a total mission data budget of 6 Mb, but it never drove off the lander and the company’s own TRL 9 assertions for its avionics rest on that undeployed, wedged operation rather than on driving [3]. The lander-side account puts the touchdown on 6 March 2025 about 250 m from the intended site, on its side in a crater, with the mission declared over the next day [20]. The MIT Media Lab page for its payloads on that rover quotes the same 10 kg and 10 cm/s and an intended range of several kilometers from the landing site, with no source given for either number [14].

Specifications

Parameter	Value	Source
Chassis	Lunar Outpost MAPP variant	[28]
Height	35 cm (artist’s impression)	[30]
Planned traverse range	2 km from lander (mission target)	[30]
Magnetometer mast height	20 cm	[29]
Rover instruments	2	[29]
Surface mission duration	10 to 13 Earth days	[28]

No mass, wheel diameter, drive speed, slope limit, obstacle capability, power, battery capacity or processor parameter for this specific flight unit appears in the Lunar Vertex publications.

Mission profile

Parameter	Value	Source
Delivery	Intuitive Machines, CLPS CP-11, third IM lander	[28]
Landing site	Reiner Gamma, 7.585 N, 58.725 W	[29]
Arrival	shortly after local sunrise	[29]
Mission duration	10 to 13 Earth days, ending at sunset	[29]
Night survival	none, by design	[29]

The lander and the whole payload are designed for one lunar daylight period. Arrival shortly after sunrise and an end 10 to 13 Earth days later is the entire operating window, which sets the traverse the rover has to complete and removes any need for night survival hardware [28]. A single-daylight-period design is also a hedge against the CLPS program’s own failure record: the most detailed public account of a lost CLPS lander, Peregrine Mission 1, traces the loss to a single helium pressure control valve that let helium flow uncontrolled into an oxidizer tank until it ruptured, found and replicated only after the fact even though the rest of the lander flew to TRL 9 [12], and a mission that asks nothing of its payload beyond ten-odd days of daylight operation has less exposure to that kind of single-point failure than one that must additionally survive a lunar night.

Mobility

Four wheels, from the MAPP product line [28]. The Lunar Vertex publications state nothing further: no suspension description, speed, gradeability, obstacle height or terramechanics result appears in them for this vehicle. A rover-agnostic wheel-soil model built for lunar terrain vehicle simulation fixes the constants a wheeled chassis of any size is designed against: cohesion 170 N/m2, friction modulus 830000 N/m3 and a sinkage exponent of 1, values meant to represent lunar mare regolith generally rather than Reiner Gamma specifically [9]. A dedicated wheel-geometry testbed built to the same end, a 20.4 kg four-wheeled platform with an adjustable center of gravity, found that a 10 percent forward weight shift turned a failed step-obstacle crossing at low attack angle into a full pass, and that in loose simulant every configuration passed a level slope but only partly managed 10 degrees and failed at 20 [6]; neither result is stated to describe this vehicle, only the general design space it was built in. The regolith itself is characterized only at the equatorial and near-side Apollo and Luna sites that underlie every published lunar geotechnical reference: a top-layer bulk density near 1.5 g/cm3 rising with depth and a friction angle in the 40s of degrees, none of it specific to Reiner Gamma [5].

Power and energy

Solar, as a property of the chassis. No generation or storage figure is published for this vehicle, and none is needed for night survival, which is not attempted [28].

Thermal

Not published. Environmental testing of the integrated rover is mentioned without a single condition or result [28]. A comparably sized solar-powered lunar micro-rover built independently of this one, MoonRanger, was designed to a surface operating band of -10 to 35 C and found its instrument electronics the limiting element in permanently shadowed terrain, exceeding that band after a few hours regardless of avionics state [8]; nothing establishes whether Lunar Vertex’s own thermal margins resemble it. The lunar diurnal environment the rover is built to survive during its short daylight window is otherwise known only from the Apollo-era record: surface temperature swinging between roughly 92 K and 374 K over a lunation, with regolith conductivity low enough that thirty centimeters of cover damps the swing to a few kelvin [5]. A NASA Glenn survey of rover concepts compiles the design envelope of +120 to -150 C at the surface, -63 to -43 C at polar sites that avoid the lunar night, and dust grains below 70 micrometers, as design bounds rather than measurements [24]. Lunar Vertex avoids the hardest part of that envelope by design. A modeling study of a 70 kg equatorial rover shows what surviving the roughly 350 hour night would take: an unshielded thermal wadi does not hold the electronics above 243 K, and a shield emissivity of 0.03 is needed [16]. That study is a simulation, and nothing in the Lunar Vertex publications indicates a wadi or any night strategy is used.

Compute and avionics

Not published.

Autonomy

Not described in the Lunar Vertex publications. Autonomous navigation is a claim made for the MAPP product line, not a measured property of this vehicle. Where Reiner Gamma sits alongside another cooperative-autonomy technology demonstration on a Nova-C mission, CADRE, that vehicle’s own multi-rover data layer is documented down to its bandwidth and interference constraints, deliberately keeping time-sensitive command traffic out of the shared database because motor-driven electromagnetic interference makes reliable transfer possible only in specific windows [13], a level of published detail neither Lunar Vertex publication offers for its own vehicle.

Communications

Not published. The rover operates within range of the lander during a single daylight period. The one number that exists for how little bandwidth a MAPP-class rover mission has had to work with is 6 Mb total, across transit and surface operations combined, on the earlier Lunar Voyage 1 flight of the same product line [3]; nothing establishes whether Lunar Vertex shares that allocation.

Payload and instruments

Instrument	Provider	Function	Source
Vector Magnetometer-Rover	Johns Hopkins APL	tetrahedral array of four commercial fluxgate sensors on a 20 cm mast	[29]
Rover Multispectral Microscope	Canadensys Aerospace	close-up imaging of soil texture, and reflectance at five ultraviolet to near-infrared LED wavelengths for composition and maturity	[29]

The tetrahedral array is a gradiometer arrangement: four sensors at known separations let the rover’s own magnetic signature be distinguished from the field it is there to measure. The same design is used on the lander, where four commercial fluxgates sit at the base of a 0.5 m mast beneath a science-grade dual ring-core magnetometer at the top [28]. The rover carries the commercial array alone, on a much shorter mast, and its value is the second measurement point rather than the better sensor.

The microscope is mounted inside the rover body rather than on an arm or a mast, so its working distance is fixed by the vehicle’s ground clearance [29].

Modes of operation

Not published.

Ground operations

Lunar Outpost operates the rover on the Moon [28]. No planning cycle or tooling is described, and the operating window is short enough that the traverse plan is effectively fixed before landing. Lunar Outpost’s own reporting of its previous Nova-C flight describes its mission control software, Stargate, running at 99.998 percent uptime commanding an undeployed rover [3]; no equivalent figure has been published for Lunar Vertex ground operations. Elsewhere in the same product line, Lunar Outpost supplies a Rover Mobility Element derived from MAPP to a terrestrial site-preparation project, drawing on the dust mitigation and thermal work done for the rover line generally rather than for this flight unit [10].

Technologies developed

The result this vehicle is built to produce is scientific rather than engineering: a magnetic field profile measured at more than one point across a crustal anomaly, with colocated close-up regolith imaging, which is what separates the competing origin hypotheses for lunar swirls [28]. The engineering point of interest is the arrangement itself, a small commercial rover chassis bought as a product and used as an instrument carrier by a laboratory that built neither the vehicle nor the lander, with the vehicle’s builder operating it on the surface [28]. That arrangement is what the decadal survey’s technology chapter is describing when it treats CLPS-delivered mobility as a category distinct from an agency-built rover: the science team’s contribution is the payload and the investigation, not the chassis or its autonomy [4]. A comparable small commercial chassis on the same kind of delivery, CubeRover, was pushed through more than 150 wheel-set trials in a simulant bin precisely because its scale sits below anything that had already flown and only extrapolations from larger NASA rovers existed beforehand [7]; Lunar Vertex’s own publications state no equivalent mobility test program for its flight unit.

Comparable small lunar rovers

The Lunar Vertex rover sits in a class of sub-50 kg lunar vehicles that is large on paper and small in flight heritage. The Science Robotics update on space robotics counts nine lunar landers and rovers launched between 2019 and 2024, four of them failures [23]. Within that class the evidence falls into four groups.

Flown and driven. Chang’e-3 Yutu and Chang’e-4 Yutu-2 are the lunar rovers whose operations are documented in detail. Their Pancam and Navcam share a mast bar with a 270 mm stereo base, Pancam images 2352 by 1728 pixels over 22.9 by 16.9 degrees, and the landers’ descent cameras returned about 4600 and 5300 images [21]. The Yutu-2 command loop shows what a relay-limited surface operation costs: a response begins about 10 s after a command, the first telemetry frame arrives 80 to 100 s later and refreshes every 24 s, so the ground needs 3 to 4 minutes to confirm execution, and every drive command carries a time limit as well as a distance [26]. A rover with a 13-day window and a lander-relayed link works under the same kind of loop. The Lunar Vertex publications do not describe theirs.

Flown but not driven. MAPP on IM-2 is the case closest to this vehicle and is described above [3][20]. The first Rashid rover was lost with the HAKUTO-R Mission 1 lander, and the Emirates Lunar Mission continues with Rashid 2, whose published description is a list of objectives with no mass, wheel or power figure [17].

Built or manifested, not flown. The Canadian Lunar Rover is a solar powered vehicle of about 42 kg and 0.4 cubic meters with six payloads, assigned to a 2029 Firefly CLPS flight and stated as an attempt to be the first solar-only rover to survive the lunar night; an earlier abstract from the same agency gave 35 kg, and the change is not explained [18]. CADRE, three small rovers on a following Intuitive Machines flight, is a technology demonstration [13]. CubeRover reached only a simulant-bin wheel test campaign in the sources held [7].

Designed or simulated only. AMALIA, the Team Italia candidate for the Google Lunar X Prize, is a conceptual design with a 30.9 kg mass budget, 5.3 kg for wheels and suspension, and drive power of 1.15 W in lunar gravity against 19 W on a 14 percent slope; all figures are analytical estimates and no prototype was built or measured [15]. A released tradespace tool for sub-50 kg lunar rovers couples a Bekker-Wong wheel-soil kernel to mass, power, thermal and traverse models, runs in about 30 ms per mission, and finds rigid four-wheel layouts Pareto-dominant across the mission profiles it covers; every input is digitized from published data and no hardware was built [25]. That finding bears on a four-wheeled chassis such as this one only as a statement about the design class, not about the flight unit.

Navigation and traverse planning

No navigation method is published for Lunar Vertex. The methods studied for rovers of this class are mostly pre-flight. Crater-based absolute localization (LunarNav) matches craters detected from lidar or stereo against an orbital landmark database, beat a 2 percent of distance traveled dead-reckoning baseline in simulated traverses and converged near 0.75 to 2 m, and was raised from TRL 2 to TRL 4; the stereo detector failed on real Chang’e imagery, so the evidence is simulation and small hand-labeled sets [22]. A transfer-learning scheme for wheel-slip classification fuses models from earlier rovers with a short post-landing calibration set, and was tested only inside a simulator [27]. A 500 m minimum traverse requirement sets the scale the Lunar Vertex rover must clear: it must leave the roughly 30 m lander exhaust disturbance zone, estimated from the Chang’e-3 analog, before its second measurement point is useful [28].

Multi-rover coordination

A 2022 JPL seminar deck surveys cooperative distributed rover exploration with distributed mapping among four multi-robot projects; it is a slide deck with single data points and no trial counts, and Lunar Vertex uses one rover [19].

What is not established

Nothing about this specific flight unit’s mass, dimensions, drive performance, power budget, thermal margins, processor, communications data rate or autonomy behavior has been published; every number available for the MAPP product line comes from a different flight of a different rover [3], and neither publication states whether APL’s integration changed it. The traverse distance the rover is expected to cover between landing and sunset is not stated in any held source. Whether the rover will complete a second magnetic-field measurement point at all depends on Lunar Vertex surviving the landing and deploying, the two steps that failed on the most recent flight of this rover family [3] and, on the CLPS program’s own most thoroughly documented failure, on hardware unrelated to the payload it carried [12]. The IM-2 lander’s tipped touchdown shows the same dependence from the lander side [20]. The comparison rovers above are mostly designs, simulations or vehicles that did not drive, so none establishes a performance expectation for this unit; only the Yutu rovers supply operating data from the lunar surface [21][26].

References